tjh.dev
Linux kernel
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While reworking the archrandom handling, commit d349ab99eec7 ("random:
handle archrandom with multiple longs") switched to the non-early
archrandom helpers in random_init(), which broke initialization of the
entropy pool from the arm64 random generator.
Indeed at that point the arm64 CPU features, which verify that all CPUs
have compatible capabilities, are not finalized so arch_get_random_seed_longs()
is unsuccessful. Instead random_init() should use the _early functions,
which check only the boot CPU on arm64. On other architectures the
_early functions directly call the normal ones.
Fixes: d349ab99eec7 ("random: handle archrandom with multiple longs")
Cc: stable@vger.kernel.org
Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Pull networking fixes from Jakub Kicinski:
"Including fixes from 802.15.4 (Zigbee et al).
Current release - regressions:
- ipa: fix bugs in the register conversion for IPA v3.1 and v3.5.1
Current release - new code bugs:
- mptcp: fix abba deadlock on fastopen
- eth: stmmac: rk3588: allow multiple gmac controllers in one system
Previous releases - regressions:
- ip: rework the fix for dflt addr selection for connected nexthop
- net: couple more fixes for misinterpreting bits in struct page
after the signature was added
Previous releases - always broken:
- ipv6: ensure sane device mtu in tunnels
- openvswitch: switch from WARN to pr_warn on a user-triggerable path
- ethtool: eeprom: fix null-deref on genl_info in dump
- ieee802154: more return code fixes for corner cases in
dgram_sendmsg
- mac802154: fix link-quality-indicator recording
- eth: mlx5: fixes for IPsec, PTP timestamps, OvS and conntrack
offload
- eth: fec: limit register access on i.MX6UL
- eth: bcm4908_enet: update TX stats after actual transmission
- can: rcar_canfd: improve IRQ handling for RZ/G2L
Misc:
- genetlink: piggy back on the newly added resv_op_start to enforce
more sanity checks on new commands"
* tag 'net-6.1-rc3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (57 commits)
net: enetc: survive memory pressure without crashing
kcm: do not sense pfmemalloc status in kcm_sendpage()
net: do not sense pfmemalloc status in skb_append_pagefrags()
net/mlx5e: Fix macsec sci endianness at rx sa update
net/mlx5e: Fix wrong bitwise comparison usage in macsec_fs_rx_add_rule function
net/mlx5e: Fix macsec rx security association (SA) update/delete
net/mlx5e: Fix macsec coverity issue at rx sa update
net/mlx5: Fix crash during sync firmware reset
net/mlx5: Update fw fatal reporter state on PCI handlers successful recover
net/mlx5e: TC, Fix cloned flow attr instance dests are not zeroed
net/mlx5e: TC, Reject forwarding from internal port to internal port
net/mlx5: Fix possible use-after-free in async command interface
net/mlx5: ASO, Create the ASO SQ with the correct timestamp format
net/mlx5e: Update restore chain id for slow path packets
net/mlx5e: Extend SKB room check to include PTP-SQ
net/mlx5: DR, Fix matcher disconnect error flow
net/mlx5: Wait for firmware to enable CRS before pci_restore_state
net/mlx5e: Do not increment ESN when updating IPsec ESN state
netdevsim: remove dir in nsim_dev_debugfs_init() when creating ports dir failed
netdevsim: fix memory leak in nsim_drv_probe() when nsim_dev_resources_register() failed
...
Pull execve fixes from Kees Cook:
- Fix an ancient signal action copy race (Bernd Edlinger)
- Fix a memory leak in ELF loader, when under memory pressure (Li
Zetao)
* tag 'execve-v6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
fs/binfmt_elf: Fix memory leak in load_elf_binary()
exec: Copy oldsighand->action under spin-lock
Under memory pressure, enetc_refill_rx_ring() may fail, and when called
during the enetc_open() -> enetc_setup_rxbdr() procedure, this is not
checked for.
An extreme case of memory pressure will result in exactly zero buffers
being allocated for the RX ring, and in such a case it is expected that
hardware drops all RX packets due to lack of buffers.
This does not happen, because the reset-default value of the consumer
and produces index is 0, and this makes the ENETC think that all buffers
have been initialized and that it owns them (when in reality none were).
The hardware guide explains this best:
| Configure the receive ring producer index register RBaPIR with a value
| of 0. The producer index is initially configured by software but owned
| by hardware after the ring has been enabled. Hardware increments the
| index when a frame is received which may consume one or more BDs.
| Hardware is not allowed to increment the producer index to match the
| consumer index since it is used to indicate an empty condition. The ring
| can hold at most RBLENR[LENGTH]-1 received BDs.
|
| Configure the receive ring consumer index register RBaCIR. The
| consumer index is owned by software and updated during operation of the
| of the BD ring by software, to indicate that any receive data occupied
| in the BD has been processed and it has been prepared for new data.
| - If consumer index and producer index are initialized to the same
| value, it indicates that all BDs in the ring have been prepared and
| hardware owns all of the entries.
| - If consumer index is initialized to producer index plus N, it would
| indicate N BDs have been prepared. Note that hardware cannot start if
| only a single buffer is prepared due to the restrictions described in
| (2).
| - Software may write consumer index to match producer index anytime
| while the ring is operational to indicate all received BDs prior have
| been processed and new BDs prepared for hardware.
Normally, the value of rx_ring->rcir (consumer index) is brought in sync
with the rx_ring->next_to_use software index, but this only happens if
page allocation ever succeeded.
When PI==CI==0, the hardware appears to receive frames and write them to
DMA address 0x0 (?!), then set the READY bit in the BD.
The enetc_clean_rx_ring() function (and its XDP derivative) is naturally
not prepared to handle such a condition. It will attempt to process
those frames using the rx_swbd structure associated with index i of the
RX ring, but that structure is not fully initialized (enetc_new_page()
does all of that). So what happens next is undefined behavior.
To operate using no buffer, we must initialize the CI to PI + 1, which
will block the hardware from advancing the CI any further, and drop
everything.
The issue was seen while adding support for zero-copy AF_XDP sockets,
where buffer memory comes from user space, which can even decide to
supply no buffers at all (example: "xdpsock --txonly"). However, the bug
is present also with the network stack code, even though it would take a
very determined person to trigger a page allocation failure at the
perfect time (a series of ifup/ifdown under memory pressure should
eventually reproduce it given enough retries).
Fixes: d4fd0404c1c9 ("enetc: Introduce basic PF and VF ENETC ethernet drivers")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Claudiu Manoil <claudiu.manoil@nxp.com>
Link: https://lore.kernel.org/r/20221027182925.3256653-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull hardening fixes from Kees Cook:
- Fix older Clang vs recent overflow KUnit test additions (Nick
Desaulniers, Kees Cook)
- Fix kern-doc visibility for overflow helpers (Kees Cook)
* tag 'hardening-v6.1-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
overflow: Refactor test skips for Clang-specific issues
overflow: disable failing tests for older clang versions
overflow: Fix kern-doc markup for functions
There is a memory leak reported by kmemleak:
unreferenced object 0xffff88817104ef80 (size 224):
comm "xfs_admin", pid 47165, jiffies 4298708825 (age 1333.476s)
hex dump (first 32 bytes):
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
60 a8 b3 00 81 88 ff ff a8 10 5a 00 81 88 ff ff `.........Z.....
backtrace:
[<ffffffff819171e1>] __alloc_file+0x21/0x250
[<ffffffff81918061>] alloc_empty_file+0x41/0xf0
[<ffffffff81948cda>] path_openat+0xea/0x3d30
[<ffffffff8194ec89>] do_filp_open+0x1b9/0x290
[<ffffffff8192660e>] do_open_execat+0xce/0x5b0
[<ffffffff81926b17>] open_exec+0x27/0x50
[<ffffffff81a69250>] load_elf_binary+0x510/0x3ed0
[<ffffffff81927759>] bprm_execve+0x599/0x1240
[<ffffffff8192a997>] do_execveat_common.isra.0+0x4c7/0x680
[<ffffffff8192b078>] __x64_sys_execve+0x88/0xb0
[<ffffffff83bbf0a5>] do_syscall_64+0x35/0x80
If "interp_elf_ex" fails to allocate memory in load_elf_binary(),
the program will take the "out_free_ph" error handing path,
resulting in "interpreter" file resource is not released.
Fix it by adding an error handing path "out_free_file", which will
release the file resource when "interp_elf_ex" failed to allocate
memory.
Fixes: 0693ffebcfe5 ("fs/binfmt_elf.c: allocate less for static executable")
Signed-off-by: Li Zetao <lizetao1@huawei.com>
Reviewed-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20221024154421.982230-1-lizetao1@huawei.com
Similar to changes done in TCP in blamed commit.
We should not sense pfmemalloc status in sendpage() methods.
Fixes: 326140063946 ("tcp: TX zerocopy should not sense pfmemalloc status")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20221027040637.1107703-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull media fixes from Mauro Carvalho Chehab:
"A bunch of patches addressing issues in the vivid driver and adding
new checks in V4L2 to validate the input parameters from some ioctls"
* tag 'media/v6.1-3' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
media: vivid.rst: loop_video is set on the capture devnode
media: vivid: set num_in/outputs to 0 if not supported
media: vivid: drop GFP_DMA32
media: vivid: fix control handler mutex deadlock
media: videodev2.h: V4L2_DV_BT_BLANKING_HEIGHT should check 'interlaced'
media: v4l2-dv-timings: add sanity checks for blanking values
media: vivid: dev->bitmap_cap wasn't freed in all cases
media: vivid: s_fbuf: add more sanity checks
Convert test exclusion into test skipping. This brings the logic for
why a test is being skipped into the test itself, instead of having to
spread ifdefs around the code. This will make cleanup easier as minimum
tests get raised. Drop __maybe_unused so missed tests will be noticed
again and clean up whitespace.
For example, clang-11 on i386:
[15:52:32] ================== overflow (18 subtests) ==================
[15:52:32] [PASSED] u8_u8__u8_overflow_test
[15:52:32] [PASSED] s8_s8__s8_overflow_test
[15:52:32] [PASSED] u16_u16__u16_overflow_test
[15:52:32] [PASSED] s16_s16__s16_overflow_test
[15:52:32] [PASSED] u32_u32__u32_overflow_test
[15:52:32] [PASSED] s32_s32__s32_overflow_test
[15:52:32] [SKIPPED] u64_u64__u64_overflow_test
[15:52:32] [SKIPPED] s64_s64__s64_overflow_test
[15:52:32] [SKIPPED] u32_u32__int_overflow_test
[15:52:32] [PASSED] u32_u32__u8_overflow_test
[15:52:32] [PASSED] u8_u8__int_overflow_test
[15:52:32] [PASSED] int_int__u8_overflow_test
[15:52:32] [PASSED] shift_sane_test
[15:52:32] [PASSED] shift_overflow_test
[15:52:32] [PASSED] shift_truncate_test
[15:52:32] [PASSED] shift_nonsense_test
[15:52:32] [PASSED] overflow_allocation_test
[15:52:32] [PASSED] overflow_size_helpers_test
[15:52:32] ==================== [PASSED] overflow =====================
[15:52:32] ============================================================
[15:52:32] Testing complete. Ran 18 tests: passed: 15, skipped: 3
Cc: Nick Desaulniers <ndesaulniers@google.com>
Cc: Nathan Chancellor <nathan@kernel.org>
Cc: Tom Rix <trix@redhat.com>
Cc: Daniel Latypov <dlatypov@google.com>
Cc: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Cc: Gwan-gyeong Mun <gwan-gyeong.mun@intel.com>
Cc: llvm@lists.linux.dev
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Tested-by: Nick Desaulniers <ndesaulniers@google.com>
Link: https://lore.kernel.org/r/20221006230017.1833458-1-keescook@chromium.org
unshare_sighand should only access oldsighand->action
while holding oldsighand->siglock, to make sure that
newsighand->action is in a consistent state.
Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Cc: stable@vger.kernel.org
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/AM8PR10MB470871DEBD1DED081F9CC391E4389@AM8PR10MB4708.EURPRD10.PROD.OUTLOOK.COM
skb_append_pagefrags() is used by af_unix and udp sendpage()
implementation so far.
In commit 326140063946 ("tcp: TX zerocopy should not sense
pfmemalloc status") we explained why we should not sense
pfmemalloc status for pages owned by user space.
We should also use skb_fill_page_desc_noacc()
in skb_append_pagefrags() to avoid following KCSAN report:
BUG: KCSAN: data-race in lru_add_fn / skb_append_pagefrags
write to 0xffffea00058fc1c8 of 8 bytes by task 17319 on cpu 0:
__list_add include/linux/list.h:73 [inline]
list_add include/linux/list.h:88 [inline]
lruvec_add_folio include/linux/mm_inline.h:323 [inline]
lru_add_fn+0x327/0x410 mm/swap.c:228
folio_batch_move_lru+0x1e1/0x2a0 mm/swap.c:246
lru_add_drain_cpu+0x73/0x250 mm/swap.c:669
lru_add_drain+0x21/0x60 mm/swap.c:773
free_pages_and_swap_cache+0x16/0x70 mm/swap_state.c:311
tlb_batch_pages_flush mm/mmu_gather.c:59 [inline]
tlb_flush_mmu_free mm/mmu_gather.c:256 [inline]
tlb_flush_mmu+0x5b2/0x640 mm/mmu_gather.c:263
tlb_finish_mmu+0x86/0x100 mm/mmu_gather.c:363
exit_mmap+0x190/0x4d0 mm/mmap.c:3098
__mmput+0x27/0x1b0 kernel/fork.c:1185
mmput+0x3d/0x50 kernel/fork.c:1207
copy_process+0x19fc/0x2100 kernel/fork.c:2518
kernel_clone+0x166/0x550 kernel/fork.c:2671
__do_sys_clone kernel/fork.c:2812 [inline]
__se_sys_clone kernel/fork.c:2796 [inline]
__x64_sys_clone+0xc3/0xf0 kernel/fork.c:2796
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
read to 0xffffea00058fc1c8 of 8 bytes by task 17325 on cpu 1:
page_is_pfmemalloc include/linux/mm.h:1817 [inline]
__skb_fill_page_desc include/linux/skbuff.h:2432 [inline]
skb_fill_page_desc include/linux/skbuff.h:2453 [inline]
skb_append_pagefrags+0x210/0x600 net/core/skbuff.c:3974
unix_stream_sendpage+0x45e/0x990 net/unix/af_unix.c:2338
kernel_sendpage+0x184/0x300 net/socket.c:3561
sock_sendpage+0x5a/0x70 net/socket.c:1054
pipe_to_sendpage+0x128/0x160 fs/splice.c:361
splice_from_pipe_feed fs/splice.c:415 [inline]
__splice_from_pipe+0x222/0x4d0 fs/splice.c:559
splice_from_pipe fs/splice.c:594 [inline]
generic_splice_sendpage+0x89/0xc0 fs/splice.c:743
do_splice_from fs/splice.c:764 [inline]
direct_splice_actor+0x80/0xa0 fs/splice.c:931
splice_direct_to_actor+0x305/0x620 fs/splice.c:886
do_splice_direct+0xfb/0x180 fs/splice.c:974
do_sendfile+0x3bf/0x910 fs/read_write.c:1255
__do_sys_sendfile64 fs/read_write.c:1323 [inline]
__se_sys_sendfile64 fs/read_write.c:1309 [inline]
__x64_sys_sendfile64+0x10c/0x150 fs/read_write.c:1309
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
value changed: 0x0000000000000000 -> 0xffffea00058fc188
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 17325 Comm: syz-executor.0 Not tainted 6.1.0-rc1-syzkaller-00158-g440b7895c990-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/11/2022
Fixes: 326140063946 ("tcp: TX zerocopy should not sense pfmemalloc status")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20221027040346.1104204-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Pull fscrypt fix from Eric Biggers:
"Fix a memory leak that was introduced by a change that went into -rc1"
* tag 'fscrypt-for-linus' of git://git.kernel.org/pub/scm/fs/fscrypt/fscrypt:
fscrypt: fix keyring memory leak on mount failure
The example on how to use and test Capture Overlay specified
the wrong video device node. Back in 2015 the loop_video control
moved from the output device to the capture device, but this
example code is still referring to the output video device.
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>
Building the overflow kunit tests with clang-11 fails with:
$ ./tools/testing/kunit/kunit.py run --arch=arm --make_options LLVM=1 \
overflow
...
ld.lld: error: undefined symbol: __mulodi4
...
Clang 11 and earlier generate unwanted libcalls for signed output,
unsigned input.
Disable these tests for now, but should these become used in the kernel
we might consider that as justification for dropping clang-11 support.
Keep the clang-11 build alive a little bit longer.
Avoid -Wunused-function warnings via __maybe_unused. To test W=1:
$ make LLVM=1 -j128 defconfig
$ ./scripts/config -e KUNIT -e KUNIT_ALL
$ make LLVM=1 -j128 olddefconfig lib/overflow_kunit.o W=1
Link: https://github.com/ClangBuiltLinux/linux/issues/1711
Link: https://github.com/llvm/llvm-project/commit/3203143f1356a4e4e3ada231156fc6da6e1a9f9d
Reported-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/20221006171751.3444575-1-ndesaulniers@google.com
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