Merge branch 'filter-next'

Daniel Borkmann says:

====================
BPF updates

We sat down and have heavily reworked the whole previous patchset
from v10 [1] to address all comments/concerns. This patchset therefore
*replaces* the internal BPF interpreter with the new layout as
discussed in [1], and migrates some exotic callers to properly use the
BPF API for a transparent upgrade. All other callers that already use
the BPF API in a way it should be used, need no further changes to run
the new internals. We also removed the sysctl knob entirely, and do not
expose any structure to userland, so that implementation details only
reside in kernel space. Since we are replacing the interpreter we had
to migrate seccomp in one patch along with the interpreter to not break
anything. When attaching a new filter, the flow can be described as
following: i) test if jit compiler is enabled and can compile the user
BPF, ii) if so, then go for it, iii) if not, then transparently migrate
the filter into the new representation, and run it in the interpreter.
Also, we have scratched the jit flag from the len attribute and made it
as initial patch in this series as Pablo has suggested in the last
feedback, thanks. For details, please refer to the patches themselves.

We did extensive testing of BPF and seccomp on the new interpreter
itself and also on the user ABIs and could not find any issues; new
performance numbers as posted in patch 8 are also still the same.

Please find more details in the patches themselves.

For all the previous history from v1 to v10, see [1]. We have decided
to drop the v11 as we have pedantically reworked the set, but of course,
included all previous feedback.

v3 -> v4:
- Applied feedback from Dave regarding swap insns
- Rebased on net-next
v2 -> v3:
- Rebased to latest net-next (i.e. w/ rxhash->hash rename)
- Fixed patch 8/9 commit message/doc as suggested by Dave
- Rest is unchanged
v1 -> v2:
- Rebased to latest net-next
- Added static to ptp_filter as suggested by Dave
- Fixed a typo in patch 8's commit message
- Rest unchanged

Thanks !

[1] http://thread.gmane.org/gmane.linux.kernel/1665858
====================

Signed-off-by: David S. Miller <[e-mail]>

Documentation/networking/filter.txt

···
 For BPF JIT developers, bpf_jit_disasm, bpf_asm and bpf_dbg provides a useful
 toolchain for developing and testing the kernel's JIT compiler.
 
+BPF kernel internals
+--------------------
+Internally, for the kernel interpreter, a different BPF instruction set
+format with similar underlying principles from BPF described in previous
+paragraphs is being used. However, the instruction set format is modelled
+closer to the underlying architecture to mimic native instruction sets, so
+that a better performance can be achieved (more details later).
+
+It is designed to be JITed with one to one mapping, which can also open up
+the possibility for GCC/LLVM compilers to generate optimized BPF code through
+a BPF backend that performs almost as fast as natively compiled code.
+
+The new instruction set was originally designed with the possible goal in
+mind to write programs in "restricted C" and compile into BPF with a optional
+GCC/LLVM backend, so that it can just-in-time map to modern 64-bit CPUs with
+minimal performance overhead over two steps, that is, C -> BPF -> native code.
+
+Currently, the new format is being used for running user BPF programs, which
+includes seccomp BPF, classic socket filters, cls_bpf traffic classifier,
+team driver's classifier for its load-balancing mode, netfilter's xt_bpf
+extension, PTP dissector/classifier, and much more. They are all internally
+converted by the kernel into the new instruction set representation and run
+in the extended interpreter. For in-kernel handlers, this all works
+transparently by using sk_unattached_filter_create() for setting up the
+filter, resp. sk_unattached_filter_destroy() for destroying it. The macro
+SK_RUN_FILTER(filter, ctx) transparently invokes the right BPF function to
+run the filter. 'filter' is a pointer to struct sk_filter that we got from
+sk_unattached_filter_create(), and 'ctx' the given context (e.g. skb pointer).
+All constraints and restrictions from sk_chk_filter() apply before a
+conversion to the new layout is being done behind the scenes!
+
+Currently, for JITing, the user BPF format is being used and current BPF JIT
+compilers reused whenever possible. In other words, we do not (yet!) perform
+a JIT compilation in the new layout, however, future work will successively
+migrate traditional JIT compilers into the new instruction format as well, so
+that they will profit from the very same benefits. Thus, when speaking about
+JIT in the following, a JIT compiler (TBD) for the new instruction format is
+meant in this context.
+
+Some core changes of the new internal format:
+
+- Number of registers increase from 2 to 10:
+
+  The old format had two registers A and X, and a hidden frame pointer. The
+  new layout extends this to be 10 internal registers and a read-only frame
+  pointer. Since 64-bit CPUs are passing arguments to functions via registers
+  the number of args from BPF program to in-kernel function is restricted
+  to 5 and one register is used to accept return value from an in-kernel
+  function. Natively, x86_64 passes first 6 arguments in registers, aarch64/
+  sparcv9/mips64 have 7 - 8 registers for arguments; x86_64 has 6 callee saved
+  registers, and aarch64/sparcv9/mips64 have 11 or more callee saved registers.
+
+  Therefore, BPF calling convention is defined as:
+
+    * R0	- return value from in-kernel function
+    * R1 - R5	- arguments from BPF program to in-kernel function
+    * R6 - R9	- callee saved registers that in-kernel function will preserve
+    * R10	- read-only frame pointer to access stack
+
+  Thus, all BPF registers map one to one to HW registers on x86_64, aarch64,
+  etc, and BPF calling convention maps directly to ABIs used by the kernel on
+  64-bit architectures.
+
+  On 32-bit architectures JIT may map programs that use only 32-bit arithmetic
+  and may let more complex programs to be interpreted.
+
+  R0 - R5 are scratch registers and BPF program needs spill/fill them if
+  necessary across calls. Note that there is only one BPF program (== one BPF
+  main routine) and it cannot call other BPF functions, it can only call
+  predefined in-kernel functions, though.
+
+- Register width increases from 32-bit to 64-bit:
+
+  Still, the semantics of the original 32-bit ALU operations are preserved
+  via 32-bit subregisters. All BPF registers are 64-bit with 32-bit lower
+  subregisters that zero-extend into 64-bit if they are being written to.
+  That behavior maps directly to x86_64 and arm64 subregister definition, but
+  makes other JITs more difficult.
+
+  32-bit architectures run 64-bit internal BPF programs via interpreter.
+  Their JITs may convert BPF programs that only use 32-bit subregisters into
+  native instruction set and let the rest being interpreted.
+
+  Operation is 64-bit, because on 64-bit architectures, pointers are also
+  64-bit wide, and we want to pass 64-bit values in/out of kernel functions,
+  so 32-bit BPF registers would otherwise require to define register-pair
+  ABI, thus, there won't be able to use a direct BPF register to HW register
+  mapping and JIT would need to do combine/split/move operations for every
+  register in and out of the function, which is complex, bug prone and slow.
+  Another reason is the use of atomic 64-bit counters.
+
+- Conditional jt/jf targets replaced with jt/fall-through:
+
+  While the original design has constructs such as "if (cond) jump_true;
+  else jump_false;", they are being replaced into alternative constructs like
+  "if (cond) jump_true; /* else fall-through */".
+
+- Introduces bpf_call insn and register passing convention for zero overhead
+  calls from/to other kernel functions:
+
+  After a kernel function call, R1 - R5 are reset to unreadable and R0 has a
+  return type of the function. Since R6 - R9 are callee saved, their state is
+  preserved across the call.
+
+Also in the new design, BPF is limited to 4096 insns, which means that any
+program will terminate quickly and will only call a fixed number of kernel
+functions. Original BPF and the new format are two operand instructions,
+which helps to do one-to-one mapping between BPF insn and x86 insn during JIT.
+
+The input context pointer for invoking the interpreter function is generic,
+its content is defined by a specific use case. For seccomp register R1 points
+to seccomp_data, for converted BPF filters R1 points to a skb.
+
+A program, that is translated internally consists of the following elements:
+
+  op:16, jt:8, jf:8, k:32    ==>    op:8, a_reg:4, x_reg:4, off:16, imm:32
+
+Just like the original BPF, the new format runs within a controlled environment,
+is deterministic and the kernel can easily prove that. The safety of the program
+can be determined in two steps: first step does depth-first-search to disallow
+loops and other CFG validation; second step starts from the first insn and
+descends all possible paths. It simulates execution of every insn and observes
+the state change of registers and stack.
+
 Misc
 ----
 
···
 
 Jay Schulist <[e-mail]>
 Daniel Borkmann <[e-mail]>
+Alexei Starovoitov <[e-mail]>

arch/arm/net/bpf_jit_32.c

···
 		bpf_jit_dump(fp->len, alloc_size, 2, ctx.target);
 
 	fp->bpf_func = (void *)ctx.target;
+	fp->jited = 1;
 out:
 	kfree(ctx.offsets);
 	return;
···
 
 void bpf_jit_free(struct sk_filter *fp)
 {
-	if (fp->bpf_func != sk_run_filter)
+	if (fp->jited)
 		module_free(NULL, fp->bpf_func);
 	kfree(fp);
 }

arch/powerpc/net/bpf_jit_comp.c

···
 		((u64 *)image)[0] = (u64)code_base;
 		((u64 *)image)[1] = local_paca->kernel_toc;
 		fp->bpf_func = (void *)image;
+		fp->jited = 1;
 	}
 out:
 	kfree(addrs);
···
 
 void bpf_jit_free(struct sk_filter *fp)
 {
-	if (fp->bpf_func != sk_run_filter)
+	if (fp->jited)
 		module_free(NULL, fp->bpf_func);
 	kfree(fp);
 }

arch/s390/net/bpf_jit_comp.c

···
 	if (jit.start) {
 		set_memory_ro((unsigned long)header, header->pages);
 		fp->bpf_func = (void *) jit.start;
+		fp->jited = 1;
 	}
 out:
 	kfree(addrs);
···
 	unsigned long addr = (unsigned long)fp->bpf_func & PAGE_MASK;
 	struct bpf_binary_header *header = (void *)addr;
 
-	if (fp->bpf_func == sk_run_filter)
+	if (!fp->jited)
 		goto free_filter;
+
 	set_memory_rw(addr, header->pages);
 	module_free(NULL, header);
+
 free_filter:
 	kfree(fp);
 }

arch/sparc/net/bpf_jit_comp.c

···
 	if (image) {
 		bpf_flush_icache(image, image + proglen);
 		fp->bpf_func = (void *)image;
+		fp->jited = 1;
 	}
 out:
 	kfree(addrs);
···
 
 void bpf_jit_free(struct sk_filter *fp)
 {
-	if (fp->bpf_func != sk_run_filter)
+	if (fp->jited)
 		module_free(NULL, fp->bpf_func);
 	kfree(fp);
 }

arch/x86/net/bpf_jit_comp.c

···
 		bpf_flush_icache(header, image + proglen);
 		set_memory_ro((unsigned long)header, header->pages);
 		fp->bpf_func = (void *)image;
+		fp->jited = 1;
 	}
 out:
 	kfree(addrs);
···
 
 void bpf_jit_free(struct sk_filter *fp)
 {
-	if (fp->bpf_func != sk_run_filter) {
+	if (fp->jited) {
 		INIT_WORK(&fp->work, bpf_jit_free_deferred);
 		schedule_work(&fp->work);
 	} else {

drivers/isdn/i4l/isdn_ppp.c

···
 	is->slcomp = NULL;
 #endif
 #ifdef CONFIG_IPPP_FILTER
-	kfree(is->pass_filter);
-	is->pass_filter = NULL;
-	kfree(is->active_filter);
-	is->active_filter = NULL;
+	if (is->pass_filter) {
+		sk_unattached_filter_destroy(is->pass_filter);
+		is->pass_filter = NULL;
+	}
+
+	if (is->active_filter) {
+		sk_unattached_filter_destroy(is->active_filter);
+		is->active_filter = NULL;
+	}
 #endif
 
 /* TODO: if this was the previous master: link the stuff to the new master */
···
 #ifdef CONFIG_IPPP_FILTER
 	case PPPIOCSPASS:
 	{
+		struct sock_fprog fprog;
 		struct sock_filter *code;
-		int len = get_filter(argp, &code);
+		int err, len = get_filter(argp, &code);
+
 		if (len < 0)
 			return len;
-		kfree(is->pass_filter);
-		is->pass_filter = code;
-		is->pass_len = len;
-		break;
+
+		fprog.len = len;
+		fprog.filter = code;
+
+		if (is->pass_filter)
+			sk_unattached_filter_destroy(is->pass_filter);
+		err = sk_unattached_filter_create(&is->pass_filter, &fprog);
+		kfree(code);
+
+		return err;
 	}
 	case PPPIOCSACTIVE:
 	{
+		struct sock_fprog fprog;
 		struct sock_filter *code;
-		int len = get_filter(argp, &code);
+		int err, len = get_filter(argp, &code);
+
 		if (len < 0)
 			return len;
-		kfree(is->active_filter);
-		is->active_filter = code;
-		is->active_len = len;
-		break;
+
+		fprog.len = len;
+		fprog.filter = code;
+
+		if (is->active_filter)
+			sk_unattached_filter_destroy(is->active_filter);
+		err = sk_unattached_filter_create(&is->active_filter, &fprog);
+		kfree(code);
+
+		return err;
 	}
 #endif /* CONFIG_IPPP_FILTER */
 	default:
···
 	}
 
 	if (is->pass_filter
-	    && sk_run_filter(skb, is->pass_filter) == 0) {
+	    && SK_RUN_FILTER(is->pass_filter, skb) == 0) {
 		if (is->debug & 0x2)
 			printk(KERN_DEBUG "IPPP: inbound frame filtered.\n");
 		kfree_skb(skb);
 		return;
 	}
 	if (!(is->active_filter
-	      && sk_run_filter(skb, is->active_filter) == 0)) {
+	      && SK_RUN_FILTER(is->active_filter, skb) == 0)) {
 		if (is->debug & 0x2)
 			printk(KERN_DEBUG "IPPP: link-active filter: resetting huptimer.\n");
 		lp->huptimer = 0;
···
 	}
 
 	if (ipt->pass_filter
-	    && sk_run_filter(skb, ipt->pass_filter) == 0) {
+	    && SK_RUN_FILTER(ipt->pass_filter, skb) == 0) {
 		if (ipt->debug & 0x4)
 			printk(KERN_DEBUG "IPPP: outbound frame filtered.\n");
 		kfree_skb(skb);
 		goto unlock;
 	}
 	if (!(ipt->active_filter
-	      && sk_run_filter(skb, ipt->active_filter) == 0)) {
+	      && SK_RUN_FILTER(ipt->active_filter, skb) == 0)) {
 		if (ipt->debug & 0x4)
 			printk(KERN_DEBUG "IPPP: link-active filter: resetting huptimer.\n");
 		lp->huptimer = 0;
···
 	}
 
 	drop |= is->pass_filter
-		&& sk_run_filter(skb, is->pass_filter) == 0;
+		&& SK_RUN_FILTER(is->pass_filter, skb) == 0;
 	drop |= is->active_filter
-		&& sk_run_filter(skb, is->active_filter) == 0;
+		&& SK_RUN_FILTER(is->active_filter, skb) == 0;
 
 	skb_push(skb, IPPP_MAX_HEADER - 4);
 	return drop;

drivers/net/ethernet/oki-semi/pch_gbe/pch_gbe_main.c

···
 			       int data);
 static void pch_gbe_set_multi(struct net_device *netdev);
 
-static struct sock_filter ptp_filter[] = {
-	PTP_FILTER
-};
-
 static int pch_ptp_match(struct sk_buff *skb, u16 uid_hi, u32 uid_lo, u16 seqid)
 {
 	u8 *data = skb->data;
···
 	u16 *hi, *id;
 	u32 lo;
 
-	if (sk_run_filter(skb, ptp_filter) == PTP_CLASS_NONE)
+	if (ptp_classify_raw(skb) == PTP_CLASS_NONE)
 		return 0;
 
 	offset = ETH_HLEN + IPV4_HLEN(data) + UDP_HLEN;
···
 
 	adapter->ptp_pdev = pci_get_bus_and_slot(adapter->pdev->bus->number,
 					       PCI_DEVFN(12, 4));
-	if (ptp_filter_init(ptp_filter, ARRAY_SIZE(ptp_filter))) {
-		dev_err(&pdev->dev, "Bad ptp filter\n");
-		ret = -EINVAL;
-		goto err_free_netdev;
-	}
 
 	netdev->netdev_ops = &pch_gbe_netdev_ops;
 	netdev->watchdog_timeo = PCH_GBE_WATCHDOG_PERIOD;

drivers/net/ethernet/ti/cpts.c

···
 
 #ifdef CONFIG_TI_CPTS
 
-static struct sock_filter ptp_filter[] = {
-	PTP_FILTER
-};
-
 #define cpts_read32(c, r)	__raw_readl(&c->reg->r)
 #define cpts_write32(c, v, r)	__raw_writel(v, &c->reg->r)
 
···
 	u64 ns = 0;
 	struct cpts_event *event;
 	struct list_head *this, *next;
-	unsigned int class = sk_run_filter(skb, ptp_filter);
+	unsigned int class = ptp_classify_raw(skb);
 	unsigned long flags;
 	u16 seqid;
 	u8 mtype;
···
 	int err, i;
 	unsigned long flags;
 
-	if (ptp_filter_init(ptp_filter, ARRAY_SIZE(ptp_filter))) {
-		pr_err("cpts: bad ptp filter\n");
-		return -EINVAL;
-	}
 	cpts->info = cpts_info;
 	cpts->clock = ptp_clock_register(&cpts->info, dev);
 	if (IS_ERR(cpts->clock)) {

drivers/net/ethernet/xscale/ixp4xx_eth.c

···
 static struct port *npe_port_tab[MAX_NPES];
 static struct dma_pool *dma_pool;
 
-static struct sock_filter ptp_filter[] = {
-	PTP_FILTER
-};
-
 static int ixp_ptp_match(struct sk_buff *skb, u16 uid_hi, u32 uid_lo, u16 seqid)
 {
 	u8 *data = skb->data;
···
 	u16 *hi, *id;
 	u32 lo;
 
-	if (sk_run_filter(skb, ptp_filter) != PTP_CLASS_V1_IPV4)
+	if (ptp_classify_raw(skb) != PTP_CLASS_V1_IPV4)
 		return 0;
 
 	offset = ETH_HLEN + IPV4_HLEN(data) + UDP_HLEN;
···
 	u32 regs_phys;
 	char phy_id[MII_BUS_ID_SIZE + 3];
 	int err;
-
-	if (ptp_filter_init(ptp_filter, ARRAY_SIZE(ptp_filter))) {
-		pr_err("ixp4xx_eth: bad ptp filter\n");
-		return -EINVAL;
-	}
 
 	if (!(dev = alloc_etherdev(sizeof(struct port))))
 		return -ENOMEM;

drivers/net/ppp/ppp_generic.c

···
 	struct sk_buff_head mrq;	/* MP: receive reconstruction queue */
 #endif /* CONFIG_PPP_MULTILINK */
 #ifdef CONFIG_PPP_FILTER
-	struct sock_filter *pass_filter;	/* filter for packets to pass */
-	struct sock_filter *active_filter;/* filter for pkts to reset idle */
-	unsigned pass_len, active_len;
+	struct sk_filter *pass_filter;	/* filter for packets to pass */
+	struct sk_filter *active_filter;/* filter for pkts to reset idle */
 #endif /* CONFIG_PPP_FILTER */
 	struct net	*ppp_net;	/* the net we belong to */
 	struct ppp_link_stats stats64;	/* 64 bit network stats */
···
 	case PPPIOCSPASS:
 	{
 		struct sock_filter *code;
+
 		err = get_filter(argp, &code);
 		if (err >= 0) {
+			struct sock_fprog fprog = {
+				.len = err,
+				.filter = code,
+			};
+
 			ppp_lock(ppp);
-			kfree(ppp->pass_filter);
-			ppp->pass_filter = code;
-			ppp->pass_len = err;
+			if (ppp->pass_filter)
+				sk_unattached_filter_destroy(ppp->pass_filter);
+			err = sk_unattached_filter_create(&ppp->pass_filter,
+							  &fprog);
+			kfree(code);
 			ppp_unlock(ppp);
-			err = 0;
 		}
 		break;
 	}
 	case PPPIOCSACTIVE:
 	{
 		struct sock_filter *code;
+
 		err = get_filter(argp, &code);
 		if (err >= 0) {
+			struct sock_fprog fprog = {
+				.len = err,
+				.filter = code,
+			};
+
 			ppp_lock(ppp);
-			kfree(ppp->active_filter);
-			ppp->active_filter = code;
-			ppp->active_len = err;
+			if (ppp->active_filter)
+				sk_unattached_filter_destroy(ppp->active_filter);
+			err = sk_unattached_filter_create(&ppp->active_filter,
+							  &fprog);
+			kfree(code);
 			ppp_unlock(ppp);
-			err = 0;
 		}
 		break;
 	}
···
 		   a four-byte PPP header on each packet */
 		*skb_push(skb, 2) = 1;
 		if (ppp->pass_filter &&
-		    sk_run_filter(skb, ppp->pass_filter) == 0) {
+		    SK_RUN_FILTER(ppp->pass_filter, skb) == 0) {
 			if (ppp->debug & 1)
 				netdev_printk(KERN_DEBUG, ppp->dev,
 					      "PPP: outbound frame "
···
 		}
 		/* if this packet passes the active filter, record the time */
 		if (!(ppp->active_filter &&
-		      sk_run_filter(skb, ppp->active_filter) == 0))
+		      SK_RUN_FILTER(ppp->active_filter, skb) == 0))
 			ppp->last_xmit = jiffies;
 		skb_pull(skb, 2);
 #else
···
 
 			*skb_push(skb, 2) = 0;
 			if (ppp->pass_filter &&
-			    sk_run_filter(skb, ppp->pass_filter) == 0) {
+			    SK_RUN_FILTER(ppp->pass_filter, skb) == 0) {
 				if (ppp->debug & 1)
 					netdev_printk(KERN_DEBUG, ppp->dev,
 						      "PPP: inbound frame "
···
 				return;
 			}
 			if (!(ppp->active_filter &&
-			      sk_run_filter(skb, ppp->active_filter) == 0))
+			      SK_RUN_FILTER(ppp->active_filter, skb) == 0))
 				ppp->last_recv = jiffies;
 			__skb_pull(skb, 2);
 		} else
···
 	ppp->minseq = -1;
 	skb_queue_head_init(&ppp->mrq);
 #endif /* CONFIG_PPP_MULTILINK */
+#ifdef CONFIG_PPP_FILTER
+	ppp->pass_filter = NULL;
+	ppp->active_filter = NULL;
+#endif /* CONFIG_PPP_FILTER */
 
 	/*
 	 * drum roll: don't forget to set
···
 	skb_queue_purge(&ppp->mrq);
 #endif /* CONFIG_PPP_MULTILINK */
 #ifdef CONFIG_PPP_FILTER
-	kfree(ppp->pass_filter);
-	ppp->pass_filter = NULL;
-	kfree(ppp->active_filter);
-	ppp->active_filter = NULL;
+	if (ppp->pass_filter) {
+		sk_unattached_filter_destroy(ppp->pass_filter);
+		ppp->pass_filter = NULL;
+	}
+
+	if (ppp->active_filter) {
+		sk_unattached_filter_destroy(ppp->active_filter);
+		ppp->active_filter = NULL;
+	}
 #endif /* CONFIG_PPP_FILTER */
 
 	kfree_skb(ppp->xmit_pending);

include/linux/filter.h

···
 #include <linux/workqueue.h>
 #include <uapi/linux/filter.h>
 
-#ifdef CONFIG_COMPAT
-/*
- * A struct sock_filter is architecture independent.
+/* Internally used and optimized filter representation with extended
+ * instruction set based on top of classic BPF.
  */
+
+/* instruction classes */
+#define BPF_ALU64	0x07	/* alu mode in double word width */
+
+/* ld/ldx fields */
+#define BPF_DW		0x18	/* double word */
+#define BPF_XADD	0xc0	/* exclusive add */
+
+/* alu/jmp fields */
+#define BPF_MOV		0xb0	/* mov reg to reg */
+#define BPF_ARSH	0xc0	/* sign extending arithmetic shift right */
+
+/* change endianness of a register */
+#define BPF_END		0xd0	/* flags for endianness conversion: */
+#define BPF_TO_LE	0x00	/* convert to little-endian */
+#define BPF_TO_BE	0x08	/* convert to big-endian */
+#define BPF_FROM_LE	BPF_TO_LE
+#define BPF_FROM_BE	BPF_TO_BE
+
+#define BPF_JNE		0x50	/* jump != */
+#define BPF_JSGT	0x60	/* SGT is signed '>', GT in x86 */
+#define BPF_JSGE	0x70	/* SGE is signed '>=', GE in x86 */
+#define BPF_CALL	0x80	/* function call */
+#define BPF_EXIT	0x90	/* function return */
+
+/* BPF has 10 general purpose 64-bit registers and stack frame. */
+#define MAX_BPF_REG	11
+
+/* BPF program can access up to 512 bytes of stack space. */
+#define MAX_BPF_STACK	512
+
+/* Arg1, context and stack frame pointer register positions. */
+#define ARG1_REG	1
+#define CTX_REG		6
+#define FP_REG		10
+
+struct sock_filter_int {
+	__u8	code;		/* opcode */
+	__u8	a_reg:4;	/* dest register */
+	__u8	x_reg:4;	/* source register */
+	__s16	off;		/* signed offset */
+	__s32	imm;		/* signed immediate constant */
+};
+
+#ifdef CONFIG_COMPAT
+/* A struct sock_filter is architecture independent. */
 struct compat_sock_fprog {
 	u16		len;
-	compat_uptr_t	filter;		/* struct sock_filter * */
+	compat_uptr_t	filter;	/* struct sock_filter * */
 };
 #endif
 
+struct sock_fprog_kern {
+	u16			len;
+	struct sock_filter	*filter;
+};
+
 struct sk_buff;
 struct sock;
+struct seccomp_data;
 
-struct sk_filter
-{
+struct sk_filter {
 	atomic_t		refcnt;
-	unsigned int         	len;	/* Number of filter blocks */
+	u32			jited:1,	/* Is our filter JIT'ed? */
+				len:31;		/* Number of filter blocks */
+	struct sock_fprog_kern	*orig_prog;	/* Original BPF program */
 	struct rcu_head		rcu;
 	unsigned int		(*bpf_func)(const struct sk_buff *skb,
-					    const struct sock_filter *filter);
+					    const struct sock_filter_int *filter);
 	union {
-		struct sock_filter     	insns[0];
+		struct sock_filter	insns[0];
+		struct sock_filter_int	insnsi[0];
 		struct work_struct	work;
 	};
 };
···
 		   offsetof(struct sk_filter, insns[proglen]));
 }
 
-extern int sk_filter(struct sock *sk, struct sk_buff *skb);
-extern unsigned int sk_run_filter(const struct sk_buff *skb,
-				  const struct sock_filter *filter);
-extern int sk_unattached_filter_create(struct sk_filter **pfp,
-				       struct sock_fprog *fprog);
-extern void sk_unattached_filter_destroy(struct sk_filter *fp);
-extern int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
-extern int sk_detach_filter(struct sock *sk);
-extern int sk_chk_filter(struct sock_filter *filter, unsigned int flen);
-extern int sk_get_filter(struct sock *sk, struct sock_filter __user *filter, unsigned len);
-extern void sk_decode_filter(struct sock_filter *filt, struct sock_filter *to);
+#define sk_filter_proglen(fprog)			\
+		(fprog->len * sizeof(fprog->filter[0]))
+
+#define SK_RUN_FILTER(filter, ctx)			\
+		(*filter->bpf_func)(ctx, filter->insnsi)
+
+int sk_filter(struct sock *sk, struct sk_buff *skb);
+
+u32 sk_run_filter_int_seccomp(const struct seccomp_data *ctx,
+			      const struct sock_filter_int *insni);
+u32 sk_run_filter_int_skb(const struct sk_buff *ctx,
+			  const struct sock_filter_int *insni);
+
+int sk_convert_filter(struct sock_filter *prog, int len,
+		      struct sock_filter_int *new_prog, int *new_len);
+
+int sk_unattached_filter_create(struct sk_filter **pfp,
+				struct sock_fprog *fprog);
+void sk_unattached_filter_destroy(struct sk_filter *fp);
+
+int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk);
+int sk_detach_filter(struct sock *sk);
+
+int sk_chk_filter(struct sock_filter *filter, unsigned int flen);
+int sk_get_filter(struct sock *sk, struct sock_filter __user *filter,
+		  unsigned int len);
+void sk_decode_filter(struct sock_filter *filt, struct sock_filter *to);
+
+void sk_filter_charge(struct sock *sk, struct sk_filter *fp);
+void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp);
 
 #ifdef CONFIG_BPF_JIT
 #include <stdarg.h>
 #include <linux/linkage.h>
 #include <linux/printk.h>
 
-extern void bpf_jit_compile(struct sk_filter *fp);
-extern void bpf_jit_free(struct sk_filter *fp);
+void bpf_jit_compile(struct sk_filter *fp);
+void bpf_jit_free(struct sk_filter *fp);
 
 static inline void bpf_jit_dump(unsigned int flen, unsigned int proglen,
 				u32 pass, void *image)
···
 		print_hex_dump(KERN_ERR, "JIT code: ", DUMP_PREFIX_OFFSET,
 			       16, 1, image, proglen, false);
 }
-#define SK_RUN_FILTER(FILTER, SKB) (*FILTER->bpf_func)(SKB, FILTER->insns)
 #else
 #include <linux/slab.h>
 static inline void bpf_jit_compile(struct sk_filter *fp)
···
 {
 	kfree(fp);
 }
-#define SK_RUN_FILTER(FILTER, SKB) sk_run_filter(SKB, FILTER->insns)
 #endif
 
 static inline int bpf_tell_extensions(void)

include/linux/isdn_ppp.h

···
   struct slcompress *slcomp;
 #endif
 #ifdef CONFIG_IPPP_FILTER
-  struct sock_filter *pass_filter;	/* filter for packets to pass */
-  struct sock_filter *active_filter;	/* filter for pkts to reset idle */
-  unsigned pass_len, active_len;
+  struct sk_filter *pass_filter;   /* filter for packets to pass */
+  struct sk_filter *active_filter; /* filter for pkts to reset idle */
 #endif
   unsigned long debug;
   struct isdn_ppp_compressor *compressor,*decompressor;

include/linux/ptp_classify.h

···
 #include <linux/if_vlan.h>
 #include <linux/ip.h>
 #include <linux/filter.h>
-#ifdef __KERNEL__
 #include <linux/in.h>
-#else
-#include <netinet/in.h>
-#endif
 
 #define PTP_CLASS_NONE  0x00 /* not a PTP event message */
 #define PTP_CLASS_V1    0x01 /* protocol version 1 */
···
 #define OP_RETA	(BPF_RET | BPF_A)
 #define OP_RETK	(BPF_RET | BPF_K)
 
-static inline int ptp_filter_init(struct sock_filter *f, int len)
-{
-	if (OP_LDH == f[0].code)
-		return sk_chk_filter(f, len);
-	else
-		return 0;
-}
-
 #define PTP_FILTER \
 	{OP_LDH,	0,   0, OFF_ETYPE		}, /*              */ \
 	{OP_JEQ,	0,  12, ETH_P_IP		}, /* f goto L20   */ \
···
 	{OP_OR,		0,   0, PTP_CLASS_L2		}, /*              */ \
 	{OP_RETA,	0,   0, 0			}, /*              */ \
 /*L6x*/	{OP_RETK,	0,   0, PTP_CLASS_NONE		},
+
+unsigned int ptp_classify_raw(const struct sk_buff *skb);
 
 #endif

include/linux/seccomp.h

···
 #ifdef CONFIG_SECCOMP_FILTER
 extern void put_seccomp_filter(struct task_struct *tsk);
 extern void get_seccomp_filter(struct task_struct *tsk);
-extern u32 seccomp_bpf_load(int off);
 #else  /* CONFIG_SECCOMP_FILTER */
 static inline void put_seccomp_filter(struct task_struct *tsk)
 {

include/net/sock.h

···
 /* Initialise core socket variables */
 void sock_init_data(struct socket *sock, struct sock *sk);
 
-void sk_filter_release_rcu(struct rcu_head *rcu);
-
-/**
- *	sk_filter_release - release a socket filter
- *	@fp: filter to remove
- *
- *	Remove a filter from a socket and release its resources.
- */
-
-static inline void sk_filter_release(struct sk_filter *fp)
-{
-	if (atomic_dec_and_test(&fp->refcnt))
-		call_rcu(&fp->rcu, sk_filter_release_rcu);
-}
-
-static inline void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
-{
-	atomic_sub(sk_filter_size(fp->len), &sk->sk_omem_alloc);
-	sk_filter_release(fp);
-}
-
-static inline void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
-{
-	atomic_inc(&fp->refcnt);
-	atomic_add(sk_filter_size(fp->len), &sk->sk_omem_alloc);
-}
-
 /*
  * Socket reference counting postulates.
  *

kernel/seccomp.c

···
 	atomic_t usage;
 	struct seccomp_filter *prev;
 	unsigned short len;  /* Instruction count */
-	struct sock_filter insns[];
+	struct sock_filter_int insnsi[];
 };
 
 /* Limit any path through the tree to 256KB worth of instructions. */
 #define MAX_INSNS_PER_PATH ((1 << 18) / sizeof(struct sock_filter))
 
-/**
- * get_u32 - returns a u32 offset into data
- * @data: a unsigned 64 bit value
- * @index: 0 or 1 to return the first or second 32-bits
- *
- * This inline exists to hide the length of unsigned long.  If a 32-bit
- * unsigned long is passed in, it will be extended and the top 32-bits will be
- * 0. If it is a 64-bit unsigned long, then whatever data is resident will be
- * properly returned.
- *
+/*
  * Endianness is explicitly ignored and left for BPF program authors to manage
  * as per the specific architecture.
  */
-static inline u32 get_u32(u64 data, int index)
+static void populate_seccomp_data(struct seccomp_data *sd)
 {
-	return ((u32 *)&data)[index];
-}
+	struct task_struct *task = current;
+	struct pt_regs *regs = task_pt_regs(task);
 
-/* Helper for bpf_load below. */
-#define BPF_DATA(_name) offsetof(struct seccomp_data, _name)
-/**
- * bpf_load: checks and returns a pointer to the requested offset
- * @off: offset into struct seccomp_data to load from
- *
- * Returns the requested 32-bits of data.
- * seccomp_check_filter() should assure that @off is 32-bit aligned
- * and not out of bounds.  Failure to do so is a BUG.
- */
-u32 seccomp_bpf_load(int off)
-{
-	struct pt_regs *regs = task_pt_regs(current);
-	if (off == BPF_DATA(nr))
-		return syscall_get_nr(current, regs);
-	if (off == BPF_DATA(arch))
-		return syscall_get_arch(current, regs);
-	if (off >= BPF_DATA(args[0]) && off < BPF_DATA(args[6])) {
-		unsigned long value;
-		int arg = (off - BPF_DATA(args[0])) / sizeof(u64);
-		int index = !!(off % sizeof(u64));
-		syscall_get_arguments(current, regs, arg, 1, &value);
-		return get_u32(value, index);
-	}
-	if (off == BPF_DATA(instruction_pointer))
-		return get_u32(KSTK_EIP(current), 0);
-	if (off == BPF_DATA(instruction_pointer) + sizeof(u32))
-		return get_u32(KSTK_EIP(current), 1);
-	/* seccomp_check_filter should make this impossible. */
-	BUG();
+	sd->nr = syscall_get_nr(task, regs);
+	sd->arch = syscall_get_arch(task, regs);
+
+	/* Unroll syscall_get_args to help gcc on arm. */
+	syscall_get_arguments(task, regs, 0, 1, (unsigned long *) &sd->args[0]);
+	syscall_get_arguments(task, regs, 1, 1, (unsigned long *) &sd->args[1]);
+	syscall_get_arguments(task, regs, 2, 1, (unsigned long *) &sd->args[2]);
+	syscall_get_arguments(task, regs, 3, 1, (unsigned long *) &sd->args[3]);
+	syscall_get_arguments(task, regs, 4, 1, (unsigned long *) &sd->args[4]);
+	syscall_get_arguments(task, regs, 5, 1, (unsigned long *) &sd->args[5]);
+
+	sd->instruction_pointer = KSTK_EIP(task);
 }
 
 /**
···
 
 		switch (code) {
 		case BPF_S_LD_W_ABS:
-			ftest->code = BPF_S_ANC_SECCOMP_LD_W;
+			ftest->code = BPF_LDX | BPF_W | BPF_ABS;
 			/* 32-bit aligned and not out of bounds. */
 			if (k >= sizeof(struct seccomp_data) || k & 3)
 				return -EINVAL;
 			continue;
 		case BPF_S_LD_W_LEN:
-			ftest->code = BPF_S_LD_IMM;
+			ftest->code = BPF_LD | BPF_IMM;
 			ftest->k = sizeof(struct seccomp_data);
 			continue;
 		case BPF_S_LDX_W_LEN:
-			ftest->code = BPF_S_LDX_IMM;
+			ftest->code = BPF_LDX | BPF_IMM;
 			ftest->k = sizeof(struct seccomp_data);
 			continue;
 		/* Explicitly include allowed calls. */
···
 		case BPF_S_JMP_JGT_X:
 		case BPF_S_JMP_JSET_K:
 		case BPF_S_JMP_JSET_X:
+			sk_decode_filter(ftest, ftest);
 			continue;
 		default:
 			return -EINVAL;
···
 static u32 seccomp_run_filters(int syscall)
 {
 	struct seccomp_filter *f;
+	struct seccomp_data sd;
 	u32 ret = SECCOMP_RET_ALLOW;
 
 	/* Ensure unexpected behavior doesn't result in failing open. */
 	if (WARN_ON(current->seccomp.filter == NULL))
 		return SECCOMP_RET_KILL;
 
+	populate_seccomp_data(&sd);
+
 	/*
 	 * All filters in the list are evaluated and the lowest BPF return
 	 * value always takes priority (ignoring the DATA).
 	 */
 	for (f = current->seccomp.filter; f; f = f->prev) {
-		u32 cur_ret = sk_run_filter(NULL, f->insns);
+		u32 cur_ret = sk_run_filter_int_seccomp(&sd, f->insnsi);
 		if ((cur_ret & SECCOMP_RET_ACTION) < (ret & SECCOMP_RET_ACTION))
 			ret = cur_ret;
 	}
···
 	struct seccomp_filter *filter;
 	unsigned long fp_size = fprog->len * sizeof(struct sock_filter);
 	unsigned long total_insns = fprog->len;
+	struct sock_filter *fp;
+	int new_len;
 	long ret;
 
 	if (fprog->len == 0 || fprog->len > BPF_MAXINSNS)
···
 				     CAP_SYS_ADMIN) != 0)
 		return -EACCES;
 
-	/* Allocate a new seccomp_filter */
-	filter = kzalloc(sizeof(struct seccomp_filter) + fp_size,
-			 GFP_KERNEL|__GFP_NOWARN);
-	if (!filter)
+	fp = kzalloc(fp_size, GFP_KERNEL|__GFP_NOWARN);
+	if (!fp)
 		return -ENOMEM;
-	atomic_set(&filter->usage, 1);
-	filter->len = fprog->len;
 
 	/* Copy the instructions from fprog. */
 	ret = -EFAULT;
-	if (copy_from_user(filter->insns, fprog->filter, fp_size))
-		goto fail;
+	if (copy_from_user(fp, fprog->filter, fp_size))
+		goto free_prog;
 
 	/* Check and rewrite the fprog via the skb checker */
-	ret = sk_chk_filter(filter->insns, filter->len);
+	ret = sk_chk_filter(fp, fprog->len);
 	if (ret)
-		goto fail;
+		goto free_prog;
 
 	/* Check and rewrite the fprog for seccomp use */
-	ret = seccomp_check_filter(filter->insns, filter->len);
+	ret = seccomp_check_filter(fp, fprog->len);
 	if (ret)
-		goto fail;
+		goto free_prog;
+
+	/* Convert 'sock_filter' insns to 'sock_filter_int' insns */
+	ret = sk_convert_filter(fp, fprog->len, NULL, &new_len);
+	if (ret)
+		goto free_prog;
+
+	/* Allocate a new seccomp_filter */
+	filter = kzalloc(sizeof(struct seccomp_filter) +
+			 sizeof(struct sock_filter_int) * new_len,
+			 GFP_KERNEL|__GFP_NOWARN);
+	if (!filter)
+		goto free_prog;
+
+	ret = sk_convert_filter(fp, fprog->len, filter->insnsi, &new_len);
+	if (ret)
+		goto free_filter;
+
+	atomic_set(&filter->usage, 1);
+	filter->len = new_len;
 
 	/*
 	 * If there is an existing filter, make it the prev and don't drop its
···
 	filter->prev = current->seccomp.filter;
 	current->seccomp.filter = filter;
 	return 0;
-fail:
+
+free_filter:
 	kfree(filter);
+free_prog:
+	kfree(fp);
 	return ret;
 }
 

net/core/filter.c

···
 /*
  * Linux Socket Filter - Kernel level socket filtering
  *
- * Author:
- *     Jay Schulist <[e-mail]>
+ * Based on the design of the Berkeley Packet Filter. The new
+ * internal format has been designed by PLUMgrid:
  *
- * Based on the design of:
- *     - The Berkeley Packet Filter
+ *	Copyright (c) 2011 - 2014 PLUMgrid, http://plumgrid.com
+ *
+ * Authors:
+ *
+ *	Jay Schulist <[e-mail]>
+ *	Alexei Starovoitov <[e-mail]>
+ *	Daniel Borkmann <[e-mail]>
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
···
 }
 EXPORT_SYMBOL(sk_filter);
 
+/* Base function for offset calculation. Needs to go into .text section,
+ * therefore keeping it non-static as well; will also be used by JITs
+ * anyway later on, so do not let the compiler omit it.
+ */
+noinline u64 __bpf_call_base(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5)
+{
+	return 0;
+}
+
 /**
- *	sk_run_filter - run a filter on a socket
- *	@skb: buffer to run the filter on
+ *	__sk_run_filter - run a filter on a given context
+ *	@ctx: buffer to run the filter on
  *	@fentry: filter to apply
  *
- * Decode and apply filter instructions to the skb->data.
- * Return length to keep, 0 for none. @skb is the data we are
- * filtering, @filter is the array of filter instructions.
- * Because all jumps are guaranteed to be before last instruction,
- * and last instruction guaranteed to be a RET, we dont need to check
- * flen. (We used to pass to this function the length of filter)
+ * Decode and apply filter instructions to the skb->data. Return length to
+ * keep, 0 for none. @ctx is the data we are operating on, @filter is the
+ * array of filter instructions.
  */
-unsigned int sk_run_filter(const struct sk_buff *skb,
-			   const struct sock_filter *fentry)
+unsigned int __sk_run_filter(void *ctx, const struct sock_filter_int *insn)
 {
+	u64 stack[MAX_BPF_STACK / sizeof(u64)];
+	u64 regs[MAX_BPF_REG], tmp;
 	void *ptr;
-	u32 A = 0;			/* Accumulator */
-	u32 X = 0;			/* Index Register */
-	u32 mem[BPF_MEMWORDS];		/* Scratch Memory Store */
-	u32 tmp;
-	int k;
+	int off;
 
-	/*
-	 * Process array of filter instructions.
-	 */
-	for (;; fentry++) {
-#if defined(CONFIG_X86_32)
-#define	K (fentry->k)
-#else
-		const u32 K = fentry->k;
-#endif
+#define K  insn->imm
+#define A  regs[insn->a_reg]
+#define X  regs[insn->x_reg]
+#define R0 regs[0]
 
-		switch (fentry->code) {
-		case BPF_S_ALU_ADD_X:
-			A += X;
-			continue;
-		case BPF_S_ALU_ADD_K:
-			A += K;
-			continue;
-		case BPF_S_ALU_SUB_X:
-			A -= X;
-			continue;
-		case BPF_S_ALU_SUB_K:
-			A -= K;
-			continue;
-		case BPF_S_ALU_MUL_X:
-			A *= X;
-			continue;
-		case BPF_S_ALU_MUL_K:
-			A *= K;
-			continue;
-		case BPF_S_ALU_DIV_X:
-			if (X == 0)
-				return 0;
-			A /= X;
-			continue;
-		case BPF_S_ALU_DIV_K:
-			A /= K;
-			continue;
-		case BPF_S_ALU_MOD_X:
-			if (X == 0)
-				return 0;
-			A %= X;
-			continue;
-		case BPF_S_ALU_MOD_K:
-			A %= K;
-			continue;
-		case BPF_S_ALU_AND_X:
-			A &= X;
-			continue;
-		case BPF_S_ALU_AND_K:
-			A &= K;
-			continue;
-		case BPF_S_ALU_OR_X:
-			A |= X;
-			continue;
-		case BPF_S_ALU_OR_K:
-			A |= K;
-			continue;
-		case BPF_S_ANC_ALU_XOR_X:
-		case BPF_S_ALU_XOR_X:
-			A ^= X;
-			continue;
-		case BPF_S_ALU_XOR_K:
-			A ^= K;
-			continue;
-		case BPF_S_ALU_LSH_X:
-			A <<= X;
-			continue;
-		case BPF_S_ALU_LSH_K:
-			A <<= K;
-			continue;
-		case BPF_S_ALU_RSH_X:
-			A >>= X;
-			continue;
-		case BPF_S_ALU_RSH_K:
-			A >>= K;
-			continue;
-		case BPF_S_ALU_NEG:
-			A = -A;
-			continue;
-		case BPF_S_JMP_JA:
-			fentry += K;
-			continue;
-		case BPF_S_JMP_JGT_K:
-			fentry += (A > K) ? fentry->jt : fentry->jf;
-			continue;
-		case BPF_S_JMP_JGE_K:
-			fentry += (A >= K) ? fentry->jt : fentry->jf;
-			continue;
-		case BPF_S_JMP_JEQ_K:
-			fentry += (A == K) ? fentry->jt : fentry->jf;
-			continue;
-		case BPF_S_JMP_JSET_K:
-			fentry += (A & K) ? fentry->jt : fentry->jf;
-			continue;
-		case BPF_S_JMP_JGT_X:
-			fentry += (A > X) ? fentry->jt : fentry->jf;
-			continue;
-		case BPF_S_JMP_JGE_X:
-			fentry += (A >= X) ? fentry->jt : fentry->jf;
-			continue;
-		case BPF_S_JMP_JEQ_X:
-			fentry += (A == X) ? fentry->jt : fentry->jf;
-			continue;
-		case BPF_S_JMP_JSET_X:
-			fentry += (A & X) ? fentry->jt : fentry->jf;
-			continue;
-		case BPF_S_LD_W_ABS:
-			k = K;
-load_w:
-			ptr = load_pointer(skb, k, 4, &tmp);
-			if (ptr != NULL) {
-				A = get_unaligned_be32(ptr);
-				continue;
-			}
-			return 0;
-		case BPF_S_LD_H_ABS:
-			k = K;
-load_h:
-			ptr = load_pointer(skb, k, 2, &tmp);
-			if (ptr != NULL) {
-				A = get_unaligned_be16(ptr);
-				continue;
-			}
-			return 0;
-		case BPF_S_LD_B_ABS:
-			k = K;
-load_b:
-			ptr = load_pointer(skb, k, 1, &tmp);
-			if (ptr != NULL) {
-				A = *(u8 *)ptr;
-				continue;
-			}
-			return 0;
-		case BPF_S_LD_W_LEN:
-			A = skb->len;
-			continue;
-		case BPF_S_LDX_W_LEN:
-			X = skb->len;
-			continue;
-		case BPF_S_LD_W_IND:
-			k = X + K;
-			goto load_w;
-		case BPF_S_LD_H_IND:
-			k = X + K;
-			goto load_h;
-		case BPF_S_LD_B_IND:
-			k = X + K;
-			goto load_b;
-		case BPF_S_LDX_B_MSH:
-			ptr = load_pointer(skb, K, 1, &tmp);
-			if (ptr != NULL) {
-				X = (*(u8 *)ptr & 0xf) << 2;
-				continue;
-			}
-			return 0;
-		case BPF_S_LD_IMM:
-			A = K;
-			continue;
-		case BPF_S_LDX_IMM:
-			X = K;
-			continue;
-		case BPF_S_LD_MEM:
-			A = mem[K];
-			continue;
-		case BPF_S_LDX_MEM:
-			X = mem[K];
-			continue;
-		case BPF_S_MISC_TAX:
-			X = A;
-			continue;
-		case BPF_S_MISC_TXA:
-			A = X;
-			continue;
-		case BPF_S_RET_K:
-			return K;
-		case BPF_S_RET_A:
-			return A;
-		case BPF_S_ST:
-			mem[K] = A;
-			continue;
-		case BPF_S_STX:
-			mem[K] = X;
-			continue;
-		case BPF_S_ANC_PROTOCOL:
-			A = ntohs(skb->protocol);
-			continue;
-		case BPF_S_ANC_PKTTYPE:
-			A = skb->pkt_type;
-			continue;
-		case BPF_S_ANC_IFINDEX:
-			if (!skb->dev)
-				return 0;
-			A = skb->dev->ifindex;
-			continue;
-		case BPF_S_ANC_MARK:
-			A = skb->mark;
-			continue;
-		case BPF_S_ANC_QUEUE:
-			A = skb->queue_mapping;
-			continue;
-		case BPF_S_ANC_HATYPE:
-			if (!skb->dev)
-				return 0;
-			A = skb->dev->type;
-			continue;
-		case BPF_S_ANC_RXHASH:
-			A = skb->hash;
-			continue;
-		case BPF_S_ANC_CPU:
-			A = raw_smp_processor_id();
-			continue;
-		case BPF_S_ANC_VLAN_TAG:
-			A = vlan_tx_tag_get(skb);
-			continue;
-		case BPF_S_ANC_VLAN_TAG_PRESENT:
-			A = !!vlan_tx_tag_present(skb);
-			continue;
-		case BPF_S_ANC_PAY_OFFSET:
-			A = __skb_get_poff(skb);
-			continue;
-		case BPF_S_ANC_NLATTR: {
-			struct nlattr *nla;
+#define CONT	 ({insn++; goto select_insn; })
+#define CONT_JMP ({insn++; goto select_insn; })
 
-			if (skb_is_nonlinear(skb))
-				return 0;
-			if (A > skb->len - sizeof(struct nlattr))
-				return 0;
+	static const void *jumptable[256] = {
+		[0 ... 255] = &&default_label,
+		/* Now overwrite non-defaults ... */
+#define DL(A, B, C)	[A|B|C] = &&A##_##B##_##C
+		DL(BPF_ALU, BPF_ADD, BPF_X),
+		DL(BPF_ALU, BPF_ADD, BPF_K),
+		DL(BPF_ALU, BPF_SUB, BPF_X),
+		DL(BPF_ALU, BPF_SUB, BPF_K),
+		DL(BPF_ALU, BPF_AND, BPF_X),
+		DL(BPF_ALU, BPF_AND, BPF_K),
+		DL(BPF_ALU, BPF_OR, BPF_X),
+		DL(BPF_ALU, BPF_OR, BPF_K),
+		DL(BPF_ALU, BPF_LSH, BPF_X),
+		DL(BPF_ALU, BPF_LSH, BPF_K),
+		DL(BPF_ALU, BPF_RSH, BPF_X),
+		DL(BPF_ALU, BPF_RSH, BPF_K),
+		DL(BPF_ALU, BPF_XOR, BPF_X),
+		DL(BPF_ALU, BPF_XOR, BPF_K),
+		DL(BPF_ALU, BPF_MUL, BPF_X),
+		DL(BPF_ALU, BPF_MUL, BPF_K),
+		DL(BPF_ALU, BPF_MOV, BPF_X),
+		DL(BPF_ALU, BPF_MOV, BPF_K),
+		DL(BPF_ALU, BPF_DIV, BPF_X),
+		DL(BPF_ALU, BPF_DIV, BPF_K),
+		DL(BPF_ALU, BPF_MOD, BPF_X),
+		DL(BPF_ALU, BPF_MOD, BPF_K),
+		DL(BPF_ALU, BPF_NEG, 0),
+		DL(BPF_ALU, BPF_END, BPF_TO_BE),
+		DL(BPF_ALU, BPF_END, BPF_TO_LE),
+		DL(BPF_ALU64, BPF_ADD, BPF_X),
+		DL(BPF_ALU64, BPF_ADD, BPF_K),
+		DL(BPF_ALU64, BPF_SUB, BPF_X),
+		DL(BPF_ALU64, BPF_SUB, BPF_K),
+		DL(BPF_ALU64, BPF_AND, BPF_X),
+		DL(BPF_ALU64, BPF_AND, BPF_K),
+		DL(BPF_ALU64, BPF_OR, BPF_X),
+		DL(BPF_ALU64, BPF_OR, BPF_K),
+		DL(BPF_ALU64, BPF_LSH, BPF_X),
+		DL(BPF_ALU64, BPF_LSH, BPF_K),
+		DL(BPF_ALU64, BPF_RSH, BPF_X),
+		DL(BPF_ALU64, BPF_RSH, BPF_K),
+		DL(BPF_ALU64, BPF_XOR, BPF_X),
+		DL(BPF_ALU64, BPF_XOR, BPF_K),
+		DL(BPF_ALU64, BPF_MUL, BPF_X),
+		DL(BPF_ALU64, BPF_MUL, BPF_K),
+		DL(BPF_ALU64, BPF_MOV, BPF_X),
+		DL(BPF_ALU64, BPF_MOV, BPF_K),
+		DL(BPF_ALU64, BPF_ARSH, BPF_X),
+		DL(BPF_ALU64, BPF_ARSH, BPF_K),
+		DL(BPF_ALU64, BPF_DIV, BPF_X),
+		DL(BPF_ALU64, BPF_DIV, BPF_K),
+		DL(BPF_ALU64, BPF_MOD, BPF_X),
+		DL(BPF_ALU64, BPF_MOD, BPF_K),
+		DL(BPF_ALU64, BPF_NEG, 0),
+		DL(BPF_JMP, BPF_CALL, 0),
+		DL(BPF_JMP, BPF_JA, 0),
+		DL(BPF_JMP, BPF_JEQ, BPF_X),
+		DL(BPF_JMP, BPF_JEQ, BPF_K),
+		DL(BPF_JMP, BPF_JNE, BPF_X),
+		DL(BPF_JMP, BPF_JNE, BPF_K),
+		DL(BPF_JMP, BPF_JGT, BPF_X),
+		DL(BPF_JMP, BPF_JGT, BPF_K),
+		DL(BPF_JMP, BPF_JGE, BPF_X),
+		DL(BPF_JMP, BPF_JGE, BPF_K),
+		DL(BPF_JMP, BPF_JSGT, BPF_X),
+		DL(BPF_JMP, BPF_JSGT, BPF_K),
+		DL(BPF_JMP, BPF_JSGE, BPF_X),
+		DL(BPF_JMP, BPF_JSGE, BPF_K),
+		DL(BPF_JMP, BPF_JSET, BPF_X),
+		DL(BPF_JMP, BPF_JSET, BPF_K),
+		DL(BPF_JMP, BPF_EXIT, 0),
+		DL(BPF_STX, BPF_MEM, BPF_B),
+		DL(BPF_STX, BPF_MEM, BPF_H),
+		DL(BPF_STX, BPF_MEM, BPF_W),
+		DL(BPF_STX, BPF_MEM, BPF_DW),
+		DL(BPF_STX, BPF_XADD, BPF_W),
+		DL(BPF_STX, BPF_XADD, BPF_DW),
+		DL(BPF_ST, BPF_MEM, BPF_B),
+		DL(BPF_ST, BPF_MEM, BPF_H),
+		DL(BPF_ST, BPF_MEM, BPF_W),
+		DL(BPF_ST, BPF_MEM, BPF_DW),
+		DL(BPF_LDX, BPF_MEM, BPF_B),
+		DL(BPF_LDX, BPF_MEM, BPF_H),
+		DL(BPF_LDX, BPF_MEM, BPF_W),
+		DL(BPF_LDX, BPF_MEM, BPF_DW),
+		DL(BPF_LD, BPF_ABS, BPF_W),
+		DL(BPF_LD, BPF_ABS, BPF_H),
+		DL(BPF_LD, BPF_ABS, BPF_B),
+		DL(BPF_LD, BPF_IND, BPF_W),
+		DL(BPF_LD, BPF_IND, BPF_H),
+		DL(BPF_LD, BPF_IND, BPF_B),
+#undef DL
+	};
 
-			nla = nla_find((struct nlattr *)&skb->data[A],
-				       skb->len - A, X);
-			if (nla)
-				A = (void *)nla - (void *)skb->data;
-			else
-				A = 0;
-			continue;
+	regs[FP_REG]  = (u64) (unsigned long) &stack[ARRAY_SIZE(stack)];
+	regs[ARG1_REG] = (u64) (unsigned long) ctx;
+
+select_insn:
+	goto *jumptable[insn->code];
+
+	/* ALU */
+#define ALU(OPCODE, OP)			\
+	BPF_ALU64_##OPCODE##_BPF_X:	\
+		A = A OP X;		\
+		CONT;			\
+	BPF_ALU_##OPCODE##_BPF_X:	\
+		A = (u32) A OP (u32) X;	\
+		CONT;			\
+	BPF_ALU64_##OPCODE##_BPF_K:	\
+		A = A OP K;		\
+		CONT;			\
+	BPF_ALU_##OPCODE##_BPF_K:	\
+		A = (u32) A OP (u32) K;	\
+		CONT;
+
+	ALU(BPF_ADD,  +)
+	ALU(BPF_SUB,  -)
+	ALU(BPF_AND,  &)
+	ALU(BPF_OR,   |)
+	ALU(BPF_LSH, <<)
+	ALU(BPF_RSH, >>)
+	ALU(BPF_XOR,  ^)
+	ALU(BPF_MUL,  *)
+#undef ALU
+	BPF_ALU_BPF_NEG_0:
+		A = (u32) -A;
+		CONT;
+	BPF_ALU64_BPF_NEG_0:
+		A = -A;
+		CONT;
+	BPF_ALU_BPF_MOV_BPF_X:
+		A = (u32) X;
+		CONT;
+	BPF_ALU_BPF_MOV_BPF_K:
+		A = (u32) K;
+		CONT;
+	BPF_ALU64_BPF_MOV_BPF_X:
+		A = X;
+		CONT;
+	BPF_ALU64_BPF_MOV_BPF_K:
+		A = K;
+		CONT;
+	BPF_ALU64_BPF_ARSH_BPF_X:
+		(*(s64 *) &A) >>= X;
+		CONT;
+	BPF_ALU64_BPF_ARSH_BPF_K:
+		(*(s64 *) &A) >>= K;
+		CONT;
+	BPF_ALU64_BPF_MOD_BPF_X:
+		tmp = A;
+		if (X)
+			A = do_div(tmp, X);
+		CONT;
+	BPF_ALU_BPF_MOD_BPF_X:
+		tmp = (u32) A;
+		if (X)
+			A = do_div(tmp, (u32) X);
+		CONT;
+	BPF_ALU64_BPF_MOD_BPF_K:
+		tmp = A;
+		if (K)
+			A = do_div(tmp, K);
+		CONT;
+	BPF_ALU_BPF_MOD_BPF_K:
+		tmp = (u32) A;
+		if (K)
+			A = do_div(tmp, (u32) K);
+		CONT;
+	BPF_ALU64_BPF_DIV_BPF_X:
+		if (X)
+			do_div(A, X);
+		CONT;
+	BPF_ALU_BPF_DIV_BPF_X:
+		tmp = (u32) A;
+		if (X)
+			do_div(tmp, (u32) X);
+		A = (u32) tmp;
+		CONT;
+	BPF_ALU64_BPF_DIV_BPF_K:
+		if (K)
+			do_div(A, K);
+		CONT;
+	BPF_ALU_BPF_DIV_BPF_K:
+		tmp = (u32) A;
+		if (K)
+			do_div(tmp, (u32) K);
+		A = (u32) tmp;
+		CONT;
+	BPF_ALU_BPF_END_BPF_TO_BE:
+		switch (K) {
+		case 16:
+			A = (__force u16) cpu_to_be16(A);
+			break;
+		case 32:
+			A = (__force u32) cpu_to_be32(A);
+			break;
+		case 64:
+			A = (__force u64) cpu_to_be64(A);
+			break;
 		}
-		case BPF_S_ANC_NLATTR_NEST: {
-			struct nlattr *nla;
-
-			if (skb_is_nonlinear(skb))
-				return 0;
-			if (A > skb->len - sizeof(struct nlattr))
-				return 0;
-
-			nla = (struct nlattr *)&skb->data[A];
-			if (nla->nla_len > A - skb->len)
-				return 0;
-
-			nla = nla_find_nested(nla, X);
-			if (nla)
-				A = (void *)nla - (void *)skb->data;
-			else
-				A = 0;
-			continue;
+		CONT;
+	BPF_ALU_BPF_END_BPF_TO_LE:
+		switch (K) {
+		case 16:
+			A = (__force u16) cpu_to_le16(A);
+			break;
+		case 32:
+			A = (__force u32) cpu_to_le32(A);
+			break;
+		case 64:
+			A = (__force u64) cpu_to_le64(A);
+			break;
 		}
-#ifdef CONFIG_SECCOMP_FILTER
-		case BPF_S_ANC_SECCOMP_LD_W:
-			A = seccomp_bpf_load(fentry->k);
-			continue;
-#endif
-		default:
-			WARN_RATELIMIT(1, "Unknown code:%u jt:%u tf:%u k:%u\n",
-				       fentry->code, fentry->jt,
-				       fentry->jf, fentry->k);
-			return 0;
+		CONT;
+
+	/* CALL */
+	BPF_JMP_BPF_CALL_0:
+		/* Function call scratches R1-R5 registers, preserves R6-R9,
+		 * and stores return value into R0.
+		 */
+		R0 = (__bpf_call_base + insn->imm)(regs[1], regs[2], regs[3],
+						   regs[4], regs[5]);
+		CONT;
+
+	/* JMP */
+	BPF_JMP_BPF_JA_0:
+		insn += insn->off;
+		CONT;
+	BPF_JMP_BPF_JEQ_BPF_X:
+		if (A == X) {
+			insn += insn->off;
+			CONT_JMP;
 		}
+		CONT;
+	BPF_JMP_BPF_JEQ_BPF_K:
+		if (A == K) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_JNE_BPF_X:
+		if (A != X) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_JNE_BPF_K:
+		if (A != K) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_JGT_BPF_X:
+		if (A > X) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_JGT_BPF_K:
+		if (A > K) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_JGE_BPF_X:
+		if (A >= X) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_JGE_BPF_K:
+		if (A >= K) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_JSGT_BPF_X:
+		if (((s64)A) > ((s64)X)) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_JSGT_BPF_K:
+		if (((s64)A) > ((s64)K)) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_JSGE_BPF_X:
+		if (((s64)A) >= ((s64)X)) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_JSGE_BPF_K:
+		if (((s64)A) >= ((s64)K)) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_JSET_BPF_X:
+		if (A & X) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_JSET_BPF_K:
+		if (A & K) {
+			insn += insn->off;
+			CONT_JMP;
+		}
+		CONT;
+	BPF_JMP_BPF_EXIT_0:
+		return R0;
+
+	/* STX and ST and LDX*/
+#define LDST(SIZEOP, SIZE)					\
+	BPF_STX_BPF_MEM_##SIZEOP:				\
+		*(SIZE *)(unsigned long) (A + insn->off) = X;	\
+		CONT;						\
+	BPF_ST_BPF_MEM_##SIZEOP:				\
+		*(SIZE *)(unsigned long) (A + insn->off) = K;	\
+		CONT;						\
+	BPF_LDX_BPF_MEM_##SIZEOP:				\
+		A = *(SIZE *)(unsigned long) (X + insn->off);	\
+		CONT;
+
+	LDST(BPF_B,   u8)
+	LDST(BPF_H,  u16)
+	LDST(BPF_W,  u32)
+	LDST(BPF_DW, u64)
+#undef LDST
+	BPF_STX_BPF_XADD_BPF_W: /* lock xadd *(u32 *)(A + insn->off) += X */
+		atomic_add((u32) X, (atomic_t *)(unsigned long)
+			   (A + insn->off));
+		CONT;
+	BPF_STX_BPF_XADD_BPF_DW: /* lock xadd *(u64 *)(A + insn->off) += X */
+		atomic64_add((u64) X, (atomic64_t *)(unsigned long)
+			     (A + insn->off));
+		CONT;
+	BPF_LD_BPF_ABS_BPF_W: /* R0 = ntohl(*(u32 *) (skb->data + K)) */
+		off = K;
+load_word:
+		/* BPF_LD + BPD_ABS and BPF_LD + BPF_IND insns are only
+		 * appearing in the programs where ctx == skb. All programs
+		 * keep 'ctx' in regs[CTX_REG] == R6, sk_convert_filter()
+		 * saves it in R6, internal BPF verifier will check that
+		 * R6 == ctx.
+		 *
+		 * BPF_ABS and BPF_IND are wrappers of function calls, so
+		 * they scratch R1-R5 registers, preserve R6-R9, and store
+		 * return value into R0.
+		 *
+		 * Implicit input:
+		 *   ctx
+		 *
+		 * Explicit input:
+		 *   X == any register
+		 *   K == 32-bit immediate
+		 *
+		 * Output:
+		 *   R0 - 8/16/32-bit skb data converted to cpu endianness
+		 */
+		ptr = load_pointer((struct sk_buff *) ctx, off, 4, &tmp);
+		if (likely(ptr != NULL)) {
+			R0 = get_unaligned_be32(ptr);
+			CONT;
+		}
+		return 0;
+	BPF_LD_BPF_ABS_BPF_H: /* R0 = ntohs(*(u16 *) (skb->data + K)) */
+		off = K;
+load_half:
+		ptr = load_pointer((struct sk_buff *) ctx, off, 2, &tmp);
+		if (likely(ptr != NULL)) {
+			R0 = get_unaligned_be16(ptr);
+			CONT;
+		}
+		return 0;
+	BPF_LD_BPF_ABS_BPF_B: /* R0 = *(u8 *) (ctx + K) */
+		off = K;
+load_byte:
+		ptr = load_pointer((struct sk_buff *) ctx, off, 1, &tmp);
+		if (likely(ptr != NULL)) {
+			R0 = *(u8 *)ptr;
+			CONT;
+		}
+		return 0;
+	BPF_LD_BPF_IND_BPF_W: /* R0 = ntohl(*(u32 *) (skb->data + X + K)) */
+		off = K + X;
+		goto load_word;
+	BPF_LD_BPF_IND_BPF_H: /* R0 = ntohs(*(u16 *) (skb->data + X + K)) */
+		off = K + X;
+		goto load_half;
+	BPF_LD_BPF_IND_BPF_B: /* R0 = *(u8 *) (skb->data + X + K) */
+		off = K + X;
+		goto load_byte;
+
+	default_label:
+		/* If we ever reach this, we have a bug somewhere. */
+		WARN_RATELIMIT(1, "unknown opcode %02x\n", insn->code);
+		return 0;
+#undef CONT_JMP
+#undef CONT
+
+#undef R0
+#undef X
+#undef A
+#undef K
+}
+
+u32 sk_run_filter_int_seccomp(const struct seccomp_data *ctx,
+			      const struct sock_filter_int *insni)
+    __attribute__ ((alias ("__sk_run_filter")));
+
+u32 sk_run_filter_int_skb(const struct sk_buff *ctx,
+			  const struct sock_filter_int *insni)
+    __attribute__ ((alias ("__sk_run_filter")));
+EXPORT_SYMBOL_GPL(sk_run_filter_int_skb);
+
+/* Helper to find the offset of pkt_type in sk_buff structure. We want
+ * to make sure its still a 3bit field starting at a byte boundary;
+ * taken from arch/x86/net/bpf_jit_comp.c.
+ */
+#define PKT_TYPE_MAX	7
+static unsigned int pkt_type_offset(void)
+{
+	struct sk_buff skb_probe = { .pkt_type = ~0, };
+	u8 *ct = (u8 *) &skb_probe;
+	unsigned int off;
+
+	for (off = 0; off < sizeof(struct sk_buff); off++) {
+		if (ct[off] == PKT_TYPE_MAX)
+			return off;
 	}
+
+	pr_err_once("Please fix %s, as pkt_type couldn't be found!\n", __func__);
+	return -1;
+}
+
+static u64 __skb_get_pay_offset(u64 ctx, u64 A, u64 X, u64 r4, u64 r5)
+{
+	struct sk_buff *skb = (struct sk_buff *)(long) ctx;
+
+	return __skb_get_poff(skb);
+}
+
+static u64 __skb_get_nlattr(u64 ctx, u64 A, u64 X, u64 r4, u64 r5)
+{
+	struct sk_buff *skb = (struct sk_buff *)(long) ctx;
+	struct nlattr *nla;
+
+	if (skb_is_nonlinear(skb))
+		return 0;
+
+	if (A > skb->len - sizeof(struct nlattr))
+		return 0;
+
+	nla = nla_find((struct nlattr *) &skb->data[A], skb->len - A, X);
+	if (nla)
+		return (void *) nla - (void *) skb->data;
 
 	return 0;
 }
-EXPORT_SYMBOL(sk_run_filter);
 
-/*
- * Security :
+static u64 __skb_get_nlattr_nest(u64 ctx, u64 A, u64 X, u64 r4, u64 r5)
+{
+	struct sk_buff *skb = (struct sk_buff *)(long) ctx;
+	struct nlattr *nla;
+
+	if (skb_is_nonlinear(skb))
+		return 0;
+
+	if (A > skb->len - sizeof(struct nlattr))
+		return 0;
+
+	nla = (struct nlattr *) &skb->data[A];
+	if (nla->nla_len > A - skb->len)
+		return 0;
+
+	nla = nla_find_nested(nla, X);
+	if (nla)
+		return (void *) nla - (void *) skb->data;
+
+	return 0;
+}
+
+static u64 __get_raw_cpu_id(u64 ctx, u64 A, u64 X, u64 r4, u64 r5)
+{
+	return raw_smp_processor_id();
+}
+
+/* Register mappings for user programs. */
+#define A_REG		0
+#define X_REG		7
+#define TMP_REG		8
+#define ARG2_REG	2
+#define ARG3_REG	3
+
+static bool convert_bpf_extensions(struct sock_filter *fp,
+				   struct sock_filter_int **insnp)
+{
+	struct sock_filter_int *insn = *insnp;
+
+	switch (fp->k) {
+	case SKF_AD_OFF + SKF_AD_PROTOCOL:
+		BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, protocol) != 2);
+
+		insn->code = BPF_LDX | BPF_MEM | BPF_H;
+		insn->a_reg = A_REG;
+		insn->x_reg = CTX_REG;
+		insn->off = offsetof(struct sk_buff, protocol);
+		insn++;
+
+		/* A = ntohs(A) [emitting a nop or swap16] */
+		insn->code = BPF_ALU | BPF_END | BPF_FROM_BE;
+		insn->a_reg = A_REG;
+		insn->imm = 16;
+		break;
+
+	case SKF_AD_OFF + SKF_AD_PKTTYPE:
+		insn->code = BPF_LDX | BPF_MEM | BPF_B;
+		insn->a_reg = A_REG;
+		insn->x_reg = CTX_REG;
+		insn->off = pkt_type_offset();
+		if (insn->off < 0)
+			return false;
+		insn++;
+
+		insn->code = BPF_ALU | BPF_AND | BPF_K;
+		insn->a_reg = A_REG;
+		insn->imm = PKT_TYPE_MAX;
+		break;
+
+	case SKF_AD_OFF + SKF_AD_IFINDEX:
+	case SKF_AD_OFF + SKF_AD_HATYPE:
+		if (FIELD_SIZEOF(struct sk_buff, dev) == 8)
+			insn->code = BPF_LDX | BPF_MEM | BPF_DW;
+		else
+			insn->code = BPF_LDX | BPF_MEM | BPF_W;
+		insn->a_reg = TMP_REG;
+		insn->x_reg = CTX_REG;
+		insn->off = offsetof(struct sk_buff, dev);
+		insn++;
+
+		insn->code = BPF_JMP | BPF_JNE | BPF_K;
+		insn->a_reg = TMP_REG;
+		insn->imm = 0;
+		insn->off = 1;
+		insn++;
+
+		insn->code = BPF_JMP | BPF_EXIT;
+		insn++;
+
+		BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, ifindex) != 4);
+		BUILD_BUG_ON(FIELD_SIZEOF(struct net_device, type) != 2);
+
+		insn->a_reg = A_REG;
+		insn->x_reg = TMP_REG;
+
+		if (fp->k == SKF_AD_OFF + SKF_AD_IFINDEX) {
+			insn->code = BPF_LDX | BPF_MEM | BPF_W;
+			insn->off = offsetof(struct net_device, ifindex);
+		} else {
+			insn->code = BPF_LDX | BPF_MEM | BPF_H;
+			insn->off = offsetof(struct net_device, type);
+		}
+		break;
+
+	case SKF_AD_OFF + SKF_AD_MARK:
+		BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, mark) != 4);
+
+		insn->code = BPF_LDX | BPF_MEM | BPF_W;
+		insn->a_reg = A_REG;
+		insn->x_reg = CTX_REG;
+		insn->off = offsetof(struct sk_buff, mark);
+		break;
+
+	case SKF_AD_OFF + SKF_AD_RXHASH:
+		BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, hash) != 4);
+
+		insn->code = BPF_LDX | BPF_MEM | BPF_W;
+		insn->a_reg = A_REG;
+		insn->x_reg = CTX_REG;
+		insn->off = offsetof(struct sk_buff, hash);
+		break;
+
+	case SKF_AD_OFF + SKF_AD_QUEUE:
+		BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, queue_mapping) != 2);
+
+		insn->code = BPF_LDX | BPF_MEM | BPF_H;
+		insn->a_reg = A_REG;
+		insn->x_reg = CTX_REG;
+		insn->off = offsetof(struct sk_buff, queue_mapping);
+		break;
+
+	case SKF_AD_OFF + SKF_AD_VLAN_TAG:
+	case SKF_AD_OFF + SKF_AD_VLAN_TAG_PRESENT:
+		BUILD_BUG_ON(FIELD_SIZEOF(struct sk_buff, vlan_tci) != 2);
+
+		insn->code = BPF_LDX | BPF_MEM | BPF_H;
+		insn->a_reg = A_REG;
+		insn->x_reg = CTX_REG;
+		insn->off = offsetof(struct sk_buff, vlan_tci);
+		insn++;
+
+		BUILD_BUG_ON(VLAN_TAG_PRESENT != 0x1000);
+
+		if (fp->k == SKF_AD_OFF + SKF_AD_VLAN_TAG) {
+			insn->code = BPF_ALU | BPF_AND | BPF_K;
+			insn->a_reg = A_REG;
+			insn->imm = ~VLAN_TAG_PRESENT;
+		} else {
+			insn->code = BPF_ALU | BPF_RSH | BPF_K;
+			insn->a_reg = A_REG;
+			insn->imm = 12;
+			insn++;
+
+			insn->code = BPF_ALU | BPF_AND | BPF_K;
+			insn->a_reg = A_REG;
+			insn->imm = 1;
+		}
+		break;
+
+	case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
+	case SKF_AD_OFF + SKF_AD_NLATTR:
+	case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
+	case SKF_AD_OFF + SKF_AD_CPU:
+		/* arg1 = ctx */
+		insn->code = BPF_ALU64 | BPF_MOV | BPF_X;
+		insn->a_reg = ARG1_REG;
+		insn->x_reg = CTX_REG;
+		insn++;
+
+		/* arg2 = A */
+		insn->code = BPF_ALU64 | BPF_MOV | BPF_X;
+		insn->a_reg = ARG2_REG;
+		insn->x_reg = A_REG;
+		insn++;
+
+		/* arg3 = X */
+		insn->code = BPF_ALU64 | BPF_MOV | BPF_X;
+		insn->a_reg = ARG3_REG;
+		insn->x_reg = X_REG;
+		insn++;
+
+		/* Emit call(ctx, arg2=A, arg3=X) */
+		insn->code = BPF_JMP | BPF_CALL;
+		switch (fp->k) {
+		case SKF_AD_OFF + SKF_AD_PAY_OFFSET:
+			insn->imm = __skb_get_pay_offset - __bpf_call_base;
+			break;
+		case SKF_AD_OFF + SKF_AD_NLATTR:
+			insn->imm = __skb_get_nlattr - __bpf_call_base;
+			break;
+		case SKF_AD_OFF + SKF_AD_NLATTR_NEST:
+			insn->imm = __skb_get_nlattr_nest - __bpf_call_base;
+			break;
+		case SKF_AD_OFF + SKF_AD_CPU:
+			insn->imm = __get_raw_cpu_id - __bpf_call_base;
+			break;
+		}
+		break;
+
+	case SKF_AD_OFF + SKF_AD_ALU_XOR_X:
+		insn->code = BPF_ALU | BPF_XOR | BPF_X;
+		insn->a_reg = A_REG;
+		insn->x_reg = X_REG;
+		break;
+
+	default:
+		/* This is just a dummy call to avoid letting the compiler
+		 * evict __bpf_call_base() as an optimization. Placed here
+		 * where no-one bothers.
+		 */
+		BUG_ON(__bpf_call_base(0, 0, 0, 0, 0) != 0);
+		return false;
+	}
+
+	*insnp = insn;
+	return true;
+}
+
+/**
+ *	sk_convert_filter - convert filter program
+ *	@prog: the user passed filter program
+ *	@len: the length of the user passed filter program
+ *	@new_prog: buffer where converted program will be stored
+ *	@new_len: pointer to store length of converted program
+ *
+ * Remap 'sock_filter' style BPF instruction set to 'sock_filter_ext' style.
+ * Conversion workflow:
+ *
+ * 1) First pass for calculating the new program length:
+ *   sk_convert_filter(old_prog, old_len, NULL, &new_len)
+ *
+ * 2) 2nd pass to remap in two passes: 1st pass finds new
+ *    jump offsets, 2nd pass remapping:
+ *   new_prog = kmalloc(sizeof(struct sock_filter_int) * new_len);
+ *   sk_convert_filter(old_prog, old_len, new_prog, &new_len);
+ *
+ * User BPF's register A is mapped to our BPF register 6, user BPF
+ * register X is mapped to BPF register 7; frame pointer is always
+ * register 10; Context 'void *ctx' is stored in register 1, that is,
+ * for socket filters: ctx == 'struct sk_buff *', for seccomp:
+ * ctx == 'struct seccomp_data *'.
+ */
+int sk_convert_filter(struct sock_filter *prog, int len,
+		      struct sock_filter_int *new_prog, int *new_len)
+{
+	int new_flen = 0, pass = 0, target, i;
+	struct sock_filter_int *new_insn;
+	struct sock_filter *fp;
+	int *addrs = NULL;
+	u8 bpf_src;
+
+	BUILD_BUG_ON(BPF_MEMWORDS * sizeof(u32) > MAX_BPF_STACK);
+	BUILD_BUG_ON(FP_REG + 1 != MAX_BPF_REG);
+
+	if (len <= 0 || len >= BPF_MAXINSNS)
+		return -EINVAL;
+
+	if (new_prog) {
+		addrs = kzalloc(len * sizeof(*addrs), GFP_KERNEL);
+		if (!addrs)
+			return -ENOMEM;
+	}
+
+do_pass:
+	new_insn = new_prog;
+	fp = prog;
+
+	if (new_insn) {
+		new_insn->code = BPF_ALU64 | BPF_MOV | BPF_X;
+		new_insn->a_reg = CTX_REG;
+		new_insn->x_reg = ARG1_REG;
+	}
+	new_insn++;
+
+	for (i = 0; i < len; fp++, i++) {
+		struct sock_filter_int tmp_insns[6] = { };
+		struct sock_filter_int *insn = tmp_insns;
+
+		if (addrs)
+			addrs[i] = new_insn - new_prog;
+
+		switch (fp->code) {
+		/* All arithmetic insns and skb loads map as-is. */
+		case BPF_ALU | BPF_ADD | BPF_X:
+		case BPF_ALU | BPF_ADD | BPF_K:
+		case BPF_ALU | BPF_SUB | BPF_X:
+		case BPF_ALU | BPF_SUB | BPF_K:
+		case BPF_ALU | BPF_AND | BPF_X:
+		case BPF_ALU | BPF_AND | BPF_K:
+		case BPF_ALU | BPF_OR | BPF_X:
+		case BPF_ALU | BPF_OR | BPF_K:
+		case BPF_ALU | BPF_LSH | BPF_X:
+		case BPF_ALU | BPF_LSH | BPF_K:
+		case BPF_ALU | BPF_RSH | BPF_X:
+		case BPF_ALU | BPF_RSH | BPF_K:
+		case BPF_ALU | BPF_XOR | BPF_X:
+		case BPF_ALU | BPF_XOR | BPF_K:
+		case BPF_ALU | BPF_MUL | BPF_X:
+		case BPF_ALU | BPF_MUL | BPF_K:
+		case BPF_ALU | BPF_DIV | BPF_X:
+		case BPF_ALU | BPF_DIV | BPF_K:
+		case BPF_ALU | BPF_MOD | BPF_X:
+		case BPF_ALU | BPF_MOD | BPF_K:
+		case BPF_ALU | BPF_NEG:
+		case BPF_LD | BPF_ABS | BPF_W:
+		case BPF_LD | BPF_ABS | BPF_H:
+		case BPF_LD | BPF_ABS | BPF_B:
+		case BPF_LD | BPF_IND | BPF_W:
+		case BPF_LD | BPF_IND | BPF_H:
+		case BPF_LD | BPF_IND | BPF_B:
+			/* Check for overloaded BPF extension and
+			 * directly convert it if found, otherwise
+			 * just move on with mapping.
+			 */
+			if (BPF_CLASS(fp->code) == BPF_LD &&
+			    BPF_MODE(fp->code) == BPF_ABS &&
+			    convert_bpf_extensions(fp, &insn))
+				break;
+
+			insn->code = fp->code;
+			insn->a_reg = A_REG;
+			insn->x_reg = X_REG;
+			insn->imm = fp->k;
+			break;
+
+		/* Jump opcodes map as-is, but offsets need adjustment. */
+		case BPF_JMP | BPF_JA:
+			target = i + fp->k + 1;
+			insn->code = fp->code;
+#define EMIT_JMP							\
+	do {								\
+		if (target >= len || target < 0)			\
+			goto err;					\
+		insn->off = addrs ? addrs[target] - addrs[i] - 1 : 0;	\
+		/* Adjust pc relative offset for 2nd or 3rd insn. */	\
+		insn->off -= insn - tmp_insns;				\
+	} while (0)
+
+			EMIT_JMP;
+			break;
+
+		case BPF_JMP | BPF_JEQ | BPF_K:
+		case BPF_JMP | BPF_JEQ | BPF_X:
+		case BPF_JMP | BPF_JSET | BPF_K:
+		case BPF_JMP | BPF_JSET | BPF_X:
+		case BPF_JMP | BPF_JGT | BPF_K:
+		case BPF_JMP | BPF_JGT | BPF_X:
+		case BPF_JMP | BPF_JGE | BPF_K:
+		case BPF_JMP | BPF_JGE | BPF_X:
+			if (BPF_SRC(fp->code) == BPF_K && (int) fp->k < 0) {
+				/* BPF immediates are signed, zero extend
+				 * immediate into tmp register and use it
+				 * in compare insn.
+				 */
+				insn->code = BPF_ALU | BPF_MOV | BPF_K;
+				insn->a_reg = TMP_REG;
+				insn->imm = fp->k;
+				insn++;
+
+				insn->a_reg = A_REG;
+				insn->x_reg = TMP_REG;
+				bpf_src = BPF_X;
+			} else {
+				insn->a_reg = A_REG;
+				insn->x_reg = X_REG;
+				insn->imm = fp->k;
+				bpf_src = BPF_SRC(fp->code);
+			}
+
+			/* Common case where 'jump_false' is next insn. */
+			if (fp->jf == 0) {
+				insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
+				target = i + fp->jt + 1;
+				EMIT_JMP;
+				break;
+			}
+
+			/* Convert JEQ into JNE when 'jump_true' is next insn. */
+			if (fp->jt == 0 && BPF_OP(fp->code) == BPF_JEQ) {
+				insn->code = BPF_JMP | BPF_JNE | bpf_src;
+				target = i + fp->jf + 1;
+				EMIT_JMP;
+				break;
+			}
+
+			/* Other jumps are mapped into two insns: Jxx and JA. */
+			target = i + fp->jt + 1;
+			insn->code = BPF_JMP | BPF_OP(fp->code) | bpf_src;
+			EMIT_JMP;
+			insn++;
+
+			insn->code = BPF_JMP | BPF_JA;
+			target = i + fp->jf + 1;
+			EMIT_JMP;
+			break;
+
+		/* ldxb 4 * ([14] & 0xf) is remaped into 6 insns. */
+		case BPF_LDX | BPF_MSH | BPF_B:
+			insn->code = BPF_ALU64 | BPF_MOV | BPF_X;
+			insn->a_reg = TMP_REG;
+			insn->x_reg = A_REG;
+			insn++;
+
+			insn->code = BPF_LD | BPF_ABS | BPF_B;
+			insn->a_reg = A_REG;
+			insn->imm = fp->k;
+			insn++;
+
+			insn->code = BPF_ALU | BPF_AND | BPF_K;
+			insn->a_reg = A_REG;
+			insn->imm = 0xf;
+			insn++;
+
+			insn->code = BPF_ALU | BPF_LSH | BPF_K;
+			insn->a_reg = A_REG;
+			insn->imm = 2;
+			insn++;
+
+			insn->code = BPF_ALU64 | BPF_MOV | BPF_X;
+			insn->a_reg = X_REG;
+			insn->x_reg = A_REG;
+			insn++;
+
+			insn->code = BPF_ALU64 | BPF_MOV | BPF_X;
+			insn->a_reg = A_REG;
+			insn->x_reg = TMP_REG;
+			break;
+
+		/* RET_K, RET_A are remaped into 2 insns. */
+		case BPF_RET | BPF_A:
+		case BPF_RET | BPF_K:
+			insn->code = BPF_ALU | BPF_MOV |
+				     (BPF_RVAL(fp->code) == BPF_K ?
+				      BPF_K : BPF_X);
+			insn->a_reg = 0;
+			insn->x_reg = A_REG;
+			insn->imm = fp->k;
+			insn++;
+
+			insn->code = BPF_JMP | BPF_EXIT;
+			break;
+
+		/* Store to stack. */
+		case BPF_ST:
+		case BPF_STX:
+			insn->code = BPF_STX | BPF_MEM | BPF_W;
+			insn->a_reg = FP_REG;
+			insn->x_reg = fp->code == BPF_ST ? A_REG : X_REG;
+			insn->off = -(BPF_MEMWORDS - fp->k) * 4;
+			break;
+
+		/* Load from stack. */
+		case BPF_LD | BPF_MEM:
+		case BPF_LDX | BPF_MEM:
+			insn->code = BPF_LDX | BPF_MEM | BPF_W;
+			insn->a_reg = BPF_CLASS(fp->code) == BPF_LD ?
+				      A_REG : X_REG;
+			insn->x_reg = FP_REG;
+			insn->off = -(BPF_MEMWORDS - fp->k) * 4;
+			break;
+
+		/* A = K or X = K */
+		case BPF_LD | BPF_IMM:
+		case BPF_LDX | BPF_IMM:
+			insn->code = BPF_ALU | BPF_MOV | BPF_K;
+			insn->a_reg = BPF_CLASS(fp->code) == BPF_LD ?
+				      A_REG : X_REG;
+			insn->imm = fp->k;
+			break;
+
+		/* X = A */
+		case BPF_MISC | BPF_TAX:
+			insn->code = BPF_ALU64 | BPF_MOV | BPF_X;
+			insn->a_reg = X_REG;
+			insn->x_reg = A_REG;
+			break;
+
+		/* A = X */
+		case BPF_MISC | BPF_TXA:
+			insn->code = BPF_ALU64 | BPF_MOV | BPF_X;
+			insn->a_reg = A_REG;
+			insn->x_reg = X_REG;
+			break;
+
+		/* A = skb->len or X = skb->len */
+		case BPF_LD | BPF_W | BPF_LEN:
+		case BPF_LDX | BPF_W | BPF_LEN:
+			insn->code = BPF_LDX | BPF_MEM | BPF_W;
+			insn->a_reg = BPF_CLASS(fp->code) == BPF_LD ?
+				      A_REG : X_REG;
+			insn->x_reg = CTX_REG;
+			insn->off = offsetof(struct sk_buff, len);
+			break;
+
+		/* access seccomp_data fields */
+		case BPF_LDX | BPF_ABS | BPF_W:
+			insn->code = BPF_LDX | BPF_MEM | BPF_W;
+			insn->a_reg = A_REG;
+			insn->x_reg = CTX_REG;
+			insn->off = fp->k;
+			break;
+
+		default:
+			goto err;
+		}
+
+		insn++;
+		if (new_prog)
+			memcpy(new_insn, tmp_insns,
+			       sizeof(*insn) * (insn - tmp_insns));
+
+		new_insn += insn - tmp_insns;
+	}
+
+	if (!new_prog) {
+		/* Only calculating new length. */
+		*new_len = new_insn - new_prog;
+		return 0;
+	}
+
+	pass++;
+	if (new_flen != new_insn - new_prog) {
+		new_flen = new_insn - new_prog;
+		if (pass > 2)
+			goto err;
+
+		goto do_pass;
+	}
+
+	kfree(addrs);
+	BUG_ON(*new_len != new_flen);
+	return 0;
+err:
+	kfree(addrs);
+	return -EINVAL;
+}
+
+/* Security:
+ *
  * A BPF program is able to use 16 cells of memory to store intermediate
- * values (check u32 mem[BPF_MEMWORDS] in sk_run_filter())
+ * values (check u32 mem[BPF_MEMWORDS] in sk_run_filter()).
+ *
  * As we dont want to clear mem[] array for each packet going through
  * sk_run_filter(), we check that filter loaded by user never try to read
  * a cell if not previously written, and we check all branches to be sure
···
 }
 EXPORT_SYMBOL(sk_chk_filter);
 
+static int sk_store_orig_filter(struct sk_filter *fp,
+				const struct sock_fprog *fprog)
+{
+	unsigned int fsize = sk_filter_proglen(fprog);
+	struct sock_fprog_kern *fkprog;
+
+	fp->orig_prog = kmalloc(sizeof(*fkprog), GFP_KERNEL);
+	if (!fp->orig_prog)
+		return -ENOMEM;
+
+	fkprog = fp->orig_prog;
+	fkprog->len = fprog->len;
+	fkprog->filter = kmemdup(fp->insns, fsize, GFP_KERNEL);
+	if (!fkprog->filter) {
+		kfree(fp->orig_prog);
+		return -ENOMEM;
+	}
+
+	return 0;
+}
+
+static void sk_release_orig_filter(struct sk_filter *fp)
+{
+	struct sock_fprog_kern *fprog = fp->orig_prog;
+
+	if (fprog) {
+		kfree(fprog->filter);
+		kfree(fprog);
+	}
+}
+
 /**
  * 	sk_filter_release_rcu - Release a socket filter by rcu_head
  *	@rcu: rcu_head that contains the sk_filter to free
  */
-void sk_filter_release_rcu(struct rcu_head *rcu)
+static void sk_filter_release_rcu(struct rcu_head *rcu)
 {
 	struct sk_filter *fp = container_of(rcu, struct sk_filter, rcu);
 
+	sk_release_orig_filter(fp);
 	bpf_jit_free(fp);
 }
-EXPORT_SYMBOL(sk_filter_release_rcu);
 
-static int __sk_prepare_filter(struct sk_filter *fp)
+/**
+ *	sk_filter_release - release a socket filter
+ *	@fp: filter to remove
+ *
+ *	Remove a filter from a socket and release its resources.
+ */
+static void sk_filter_release(struct sk_filter *fp)
+{
+	if (atomic_dec_and_test(&fp->refcnt))
+		call_rcu(&fp->rcu, sk_filter_release_rcu);
+}
+
+void sk_filter_uncharge(struct sock *sk, struct sk_filter *fp)
+{
+	atomic_sub(sk_filter_size(fp->len), &sk->sk_omem_alloc);
+	sk_filter_release(fp);
+}
+
+void sk_filter_charge(struct sock *sk, struct sk_filter *fp)
+{
+	atomic_inc(&fp->refcnt);
+	atomic_add(sk_filter_size(fp->len), &sk->sk_omem_alloc);
+}
+
+static struct sk_filter *__sk_migrate_realloc(struct sk_filter *fp,
+					      struct sock *sk,
+					      unsigned int len)
+{
+	struct sk_filter *fp_new;
+
+	if (sk == NULL)
+		return krealloc(fp, len, GFP_KERNEL);
+
+	fp_new = sock_kmalloc(sk, len, GFP_KERNEL);
+	if (fp_new) {
+		memcpy(fp_new, fp, sizeof(struct sk_filter));
+		/* As we're kepping orig_prog in fp_new along,
+		 * we need to make sure we're not evicting it
+		 * from the old fp.
+		 */
+		fp->orig_prog = NULL;
+		sk_filter_uncharge(sk, fp);
+	}
+
+	return fp_new;
+}
+
+static struct sk_filter *__sk_migrate_filter(struct sk_filter *fp,
+					     struct sock *sk)
+{
+	struct sock_filter *old_prog;
+	struct sk_filter *old_fp;
+	int i, err, new_len, old_len = fp->len;
+
+	/* We are free to overwrite insns et al right here as it
+	 * won't be used at this point in time anymore internally
+	 * after the migration to the internal BPF instruction
+	 * representation.
+	 */
+	BUILD_BUG_ON(sizeof(struct sock_filter) !=
+		     sizeof(struct sock_filter_int));
+
+	/* For now, we need to unfiddle BPF_S_* identifiers in place.
+	 * This can sooner or later on be subject to removal, e.g. when
+	 * JITs have been converted.
+	 */
+	for (i = 0; i < fp->len; i++)
+		sk_decode_filter(&fp->insns[i], &fp->insns[i]);
+
+	/* Conversion cannot happen on overlapping memory areas,
+	 * so we need to keep the user BPF around until the 2nd
+	 * pass. At this time, the user BPF is stored in fp->insns.
+	 */
+	old_prog = kmemdup(fp->insns, old_len * sizeof(struct sock_filter),
+			   GFP_KERNEL);
+	if (!old_prog) {
+		err = -ENOMEM;
+		goto out_err;
+	}
+
+	/* 1st pass: calculate the new program length. */
+	err = sk_convert_filter(old_prog, old_len, NULL, &new_len);
+	if (err)
+		goto out_err_free;
+
+	/* Expand fp for appending the new filter representation. */
+	old_fp = fp;
+	fp = __sk_migrate_realloc(old_fp, sk, sk_filter_size(new_len));
+	if (!fp) {
+		/* The old_fp is still around in case we couldn't
+		 * allocate new memory, so uncharge on that one.
+		 */
+		fp = old_fp;
+		err = -ENOMEM;
+		goto out_err_free;
+	}
+
+	fp->bpf_func = sk_run_filter_int_skb;
+	fp->len = new_len;
+
+	/* 2nd pass: remap sock_filter insns into sock_filter_int insns. */
+	err = sk_convert_filter(old_prog, old_len, fp->insnsi, &new_len);
+	if (err)
+		/* 2nd sk_convert_filter() can fail only if it fails
+		 * to allocate memory, remapping must succeed. Note,
+		 * that at this time old_fp has already been released
+		 * by __sk_migrate_realloc().
+		 */
+		goto out_err_free;
+
+	kfree(old_prog);
+	return fp;
+
+out_err_free:
+	kfree(old_prog);
+out_err:
+	/* Rollback filter setup. */
+	if (sk != NULL)
+		sk_filter_uncharge(sk, fp);
+	else
+		kfree(fp);
+	return ERR_PTR(err);
+}
+
+static struct sk_filter *__sk_prepare_filter(struct sk_filter *fp,
+					     struct sock *sk)
 {
 	int err;
 
-	fp->bpf_func = sk_run_filter;
+	fp->bpf_func = NULL;
+	fp->jited = 0;
 
 	err = sk_chk_filter(fp->insns, fp->len);
 	if (err)
-		return err;
+		return ERR_PTR(err);
 
+	/* Probe if we can JIT compile the filter and if so, do
+	 * the compilation of the filter.
+	 */
 	bpf_jit_compile(fp);
-	return 0;
+
+	/* JIT compiler couldn't process this filter, so do the
+	 * internal BPF translation for the optimized interpreter.
+	 */
+	if (!fp->jited)
+		fp = __sk_migrate_filter(fp, sk);
+
+	return fp;
 }
 
 /**
···
 int sk_unattached_filter_create(struct sk_filter **pfp,
 				struct sock_fprog *fprog)
 {
+	unsigned int fsize = sk_filter_proglen(fprog);
 	struct sk_filter *fp;
-	unsigned int fsize = sizeof(struct sock_filter) * fprog->len;
-	int err;
 
 	/* Make sure new filter is there and in the right amounts. */
 	if (fprog->filter == NULL)
···
 	fp = kmalloc(sk_filter_size(fprog->len), GFP_KERNEL);
 	if (!fp)
 		return -ENOMEM;
+
 	memcpy(fp->insns, fprog->filter, fsize);
 
 	atomic_set(&fp->refcnt, 1);
 	fp->len = fprog->len;
+	/* Since unattached filters are not copied back to user
+	 * space through sk_get_filter(), we do not need to hold
+	 * a copy here, and can spare us the work.
+	 */
+	fp->orig_prog = NULL;
 
-	err = __sk_prepare_filter(fp);
-	if (err)
-		goto free_mem;
+	/* __sk_prepare_filter() already takes care of uncharging
+	 * memory in case something goes wrong.
+	 */
+	fp = __sk_prepare_filter(fp, NULL);
+	if (IS_ERR(fp))
+		return PTR_ERR(fp);
 
 	*pfp = fp;
 	return 0;
-free_mem:
-	kfree(fp);
-	return err;
 }
 EXPORT_SYMBOL_GPL(sk_unattached_filter_create);
 
···
 int sk_attach_filter(struct sock_fprog *fprog, struct sock *sk)
 {
 	struct sk_filter *fp, *old_fp;
-	unsigned int fsize = sizeof(struct sock_filter) * fprog->len;
+	unsigned int fsize = sk_filter_proglen(fprog);
 	unsigned int sk_fsize = sk_filter_size(fprog->len);
 	int err;
 
···
 	fp = sock_kmalloc(sk, sk_fsize, GFP_KERNEL);
 	if (!fp)
 		return -ENOMEM;
+
 	if (copy_from_user(fp->insns, fprog->filter, fsize)) {
 		sock_kfree_s(sk, fp, sk_fsize);
 		return -EFAULT;
···
 	atomic_set(&fp->refcnt, 1);
 	fp->len = fprog->len;
 
-	err = __sk_prepare_filter(fp);
+	err = sk_store_orig_filter(fp, fprog);
 	if (err) {
 		sk_filter_uncharge(sk, fp);
-		return err;
+		return -ENOMEM;
 	}
+
+	/* __sk_prepare_filter() already takes care of uncharging
+	 * memory in case something goes wrong.
+	 */
+	fp = __sk_prepare_filter(fp, sk);
+	if (IS_ERR(fp))
+		return PTR_ERR(fp);
 
 	old_fp = rcu_dereference_protected(sk->sk_filter,
 					   sock_owned_by_user(sk));
···
 
 	if (old_fp)
 		sk_filter_uncharge(sk, old_fp);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(sk_attach_filter);
···
 		sk_filter_uncharge(sk, filter);
 		ret = 0;
 	}
+
 	return ret;
 }
 EXPORT_SYMBOL_GPL(sk_detach_filter);
···
 	to->k = filt->k;
 }
 
-int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf, unsigned int len)
+int sk_get_filter(struct sock *sk, struct sock_filter __user *ubuf,
+		  unsigned int len)
 {
+	struct sock_fprog_kern *fprog;
 	struct sk_filter *filter;
-	int i, ret;
+	int ret = 0;
 
 	lock_sock(sk);
 	filter = rcu_dereference_protected(sk->sk_filter,
-			sock_owned_by_user(sk));
-	ret = 0;
+					   sock_owned_by_user(sk));
 	if (!filter)
 		goto out;
-	ret = filter->len;
+
+	/* We're copying the filter that has been originally attached,
+	 * so no conversion/decode needed anymore.
+	 */
+	fprog = filter->orig_prog;
+
+	ret = fprog->len;
 	if (!len)
+		/* User space only enquires number of filter blocks. */
 		goto out;
+
 	ret = -EINVAL;
-	if (len < filter->len)
+	if (len < fprog->len)
 		goto out;
 
 	ret = -EFAULT;
-	for (i = 0; i < filter->len; i++) {
-		struct sock_filter fb;
+	if (copy_to_user(ubuf, fprog->filter, sk_filter_proglen(fprog)))
+		goto out;
 
-		sk_decode_filter(&filter->insns[i], &fb);
-		if (copy_to_user(&ubuf[i], &fb, sizeof(fb)))
-			goto out;
-	}
-
-	ret = filter->len;
+	/* Instead of bytes, the API requests to return the number
+	 * of filter blocks.
+	 */
+	ret = fprog->len;
 out:
 	release_sock(sk);
 	return ret;

net/core/sock_diag.c

···
 int sock_diag_put_filterinfo(struct user_namespace *user_ns, struct sock *sk,
 			     struct sk_buff *skb, int attrtype)
 {
-	struct nlattr *attr;
+	struct sock_fprog_kern *fprog;
 	struct sk_filter *filter;
-	unsigned int len;
+	struct nlattr *attr;
+	unsigned int flen;
 	int err = 0;
 
 	if (!ns_capable(user_ns, CAP_NET_ADMIN)) {
···
 	}
 
 	rcu_read_lock();
-
 	filter = rcu_dereference(sk->sk_filter);
-	len = filter ? filter->len * sizeof(struct sock_filter) : 0;
+	if (!filter)
+		goto out;
 
-	attr = nla_reserve(skb, attrtype, len);
+	fprog = filter->orig_prog;
+	flen = sk_filter_proglen(fprog);
+
+	attr = nla_reserve(skb, attrtype, flen);
 	if (attr == NULL) {
 		err = -EMSGSIZE;
 		goto out;
 	}
 
-	if (filter) {
-		struct sock_filter *fb = (struct sock_filter *)nla_data(attr);
-		int i;
-
-		for (i = 0; i < filter->len; i++, fb++)
-			sk_decode_filter(&filter->insns[i], fb);
-	}
-
+	memcpy(nla_data(attr), fprog->filter, flen);
 out:
 	rcu_read_unlock();
 	return err;

net/core/timestamping.c

···
 #include <linux/skbuff.h>
 #include <linux/export.h>
 
-static struct sock_filter ptp_filter[] = {
-	PTP_FILTER
-};
+static struct sk_filter *ptp_insns __read_mostly;
+
+unsigned int ptp_classify_raw(const struct sk_buff *skb)
+{
+	return SK_RUN_FILTER(ptp_insns, skb);
+}
+EXPORT_SYMBOL_GPL(ptp_classify_raw);
 
 static unsigned int classify(const struct sk_buff *skb)
 {
-	if (likely(skb->dev &&
-		   skb->dev->phydev &&
+	if (likely(skb->dev && skb->dev->phydev &&
 		   skb->dev->phydev->drv))
-		return sk_run_filter(skb, ptp_filter);
+		return ptp_classify_raw(skb);
 	else
 		return PTP_CLASS_NONE;
 }
···
 		if (likely(phydev->drv->txtstamp)) {
 			if (!atomic_inc_not_zero(&sk->sk_refcnt))
 				return;
+
 			clone = skb_clone(skb, GFP_ATOMIC);
 			if (!clone) {
 				sock_put(sk);
 				return;
 			}
+
 			clone->sk = sk;
 			phydev->drv->txtstamp(phydev, clone, type);
 		}
···
 	}
 
 	*skb_hwtstamps(skb) = *hwtstamps;
+
 	serr = SKB_EXT_ERR(skb);
 	memset(serr, 0, sizeof(*serr));
 	serr->ee.ee_errno = ENOMSG;
 	serr->ee.ee_origin = SO_EE_ORIGIN_TIMESTAMPING;
 	skb->sk = NULL;
+
 	err = sock_queue_err_skb(sk, skb);
+
 	sock_put(sk);
 	if (err)
 		kfree_skb(skb);
···
 
 void __init skb_timestamping_init(void)
 {
-	BUG_ON(sk_chk_filter(ptp_filter, ARRAY_SIZE(ptp_filter)));
+	static struct sock_filter ptp_filter[] = { PTP_FILTER };
+	struct sock_fprog ptp_prog = {
+		.len = ARRAY_SIZE(ptp_filter), .filter = ptp_filter,
+	};
+
+	BUG_ON(sk_unattached_filter_create(&ptp_insns, &ptp_prog));
 }