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Linux kernel
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The user-provided value to setsockopt(SO_RCVLOWAT) can be
larger than the maximum possible receive buffer. Such values
mute POLLIN signals on the socket which can stall progress
on the socket.
Limit the user-provided value to half of the maximum receive
buffer, i.e., half of sk_rcvbuf when the receive buffer size
is set by the user, or otherwise half of sysctl_tcp_rmem[2].
Fixes: d1361840f8c5 ("tcp: fix SO_RCVLOWAT and RCVBUF autotuning")
Signed-off-by: Soheil Hassas Yeganeh <soheil@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
DP83620 register set is compatible with the DP83848, but it also supports
100base-FX. When the hardware is configured such as that fiber mode is
enabled, autonegotiation is not possible.
The chip, however, doesn't expose this information via BMSR_ANEGCAPABLE.
Instead, this bit is always set high, even if the particular hardware
configuration makes it so that auto negotiation is not possible [1]. Under
these circumstances, the phy subsystem keeps trying for autonegotiation to
happen, without success.
Hereby, we inspect BMCR_ANENABLE bit after genphy_config_init, which on
reset is set to 0 when auto negotiation is disabled, and so we use this
value instead of BMSR_ANEGCAPABLE.
[1] https://e2e.ti.com/support/interface/ethernet/f/903/p/697165/2571170
Signed-off-by: Alvaro Gamez Machado <alvaro.gamez@hazent.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
fchownat() doesn't even hold refcnt of fd until it figures out
fd is really needed (otherwise is ignored) and releases it after
it resolves the path. This means sock_close() could race with
sockfs_setattr(), which leads to a NULL pointer dereference
since typically we set sock->sk to NULL in ->release().
As pointed out by Al, this is unique to sockfs. So we can fix this
in socket layer by acquiring inode_lock in sock_close() and
checking against NULL in sockfs_setattr().
sock_release() is called in many places, only the sock_close()
path matters here. And fortunately, this should not affect normal
sock_close() as it is only called when the last fd refcnt is gone.
It only affects sock_close() with a parallel sockfs_setattr() in
progress, which is not common.
Fixes: 86741ec25462 ("net: core: Add a UID field to struct sock.")
Reported-by: shankarapailoor <shankarapailoor@gmail.com>
Cc: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Cc: Lorenzo Colitti <lorenzo@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Callers of br_fdb_find() need to hold the hash lock, which
br_fdb_find_port() doesn't do. However, since br_fdb_find_port() is not
doing any actual FDB manipulation, the hash lock is not really needed at
all. So convert to br_fdb_find_rcu(), surrounded by rcu_read_lock() /
_unlock() pair.
The device pointer copied from inside the FDB entry is then kept alive
by the RTNL lock, which br_fdb_find_port() asserts.
Fixes: 4d4fd36126d6 ("net: bridge: Publish bridge accessor functions")
Signed-off-by: Petr Machata <petrm@mellanox.com>
Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
After commit 6b229cf77d68 ("udp: add batching to udp_rmem_release()")
the sk_rmem_alloc field does not measure exactly anymore the
receive queue length, because we batch the rmem release. The issue
is really apparent only after commit 0d4a6608f68c ("udp: do rmem bulk
free even if the rx sk queue is empty"): the user space can easily
check for an empty socket with not-0 queue length reported by the 'ss'
tool or the procfs interface.
We need to use a custom UDP helper to report the correct queue length,
taking into account the forward allocation deficit.
Reported-by: trevor.francis@46labs.com
Fixes: 6b229cf77d68 ("UDP: add batching to udp_rmem_release()")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 4a0e3e989d66 ("cdc_ncm: Add support for moving NDP to end
of NCM frame") added logic to reserve space for the NDP at the
end of the NTB/skb. This reservation did not take the final
alignment of the NDP into account, causing us to reserve too
little space. Additionally the padding prior to NDP addition did
not ensure there was enough space for the NDP.
The NTB/skb with the NDP appended would then exceed the configured
max size. This caused the final padding of the NTB to use a
negative count, padding to almost INT_MAX, and resulting in:
[60103.825970] BUG: unable to handle kernel paging request at ffff9641f2004000
[60103.825998] IP: __memset+0x24/0x30
[60103.826001] PGD a6a06067 P4D a6a06067 PUD 4f65a063 PMD 72003063 PTE 0
[60103.826013] Oops: 0002 [#1] SMP NOPTI
[60103.826018] Modules linked in: (removed(
[60103.826158] CPU: 0 PID: 5990 Comm: Chrome_DevTools Tainted: G O 4.14.0-3-amd64 #1 Debian 4.14.17-1
[60103.826162] Hardware name: LENOVO 20081 BIOS 41CN28WW(V2.04) 05/03/2012
[60103.826166] task: ffff964193484fc0 task.stack: ffffb2890137c000
[60103.826171] RIP: 0010:__memset+0x24/0x30
[60103.826174] RSP: 0000:ffff964316c03b68 EFLAGS: 00010216
[60103.826178] RAX: 0000000000000000 RBX: 00000000fffffffd RCX: 000000001ffa5000
[60103.826181] RDX: 0000000000000005 RSI: 0000000000000000 RDI: ffff9641f2003ffc
[60103.826184] RBP: ffff964192f6c800 R08: 00000000304d434e R09: ffff9641f1d2c004
[60103.826187] R10: 0000000000000002 R11: 00000000000005ae R12: ffff9642e6957a80
[60103.826190] R13: ffff964282ff2ee8 R14: 000000000000000d R15: ffff9642e4843900
[60103.826194] FS: 00007f395aaf6700(0000) GS:ffff964316c00000(0000) knlGS:0000000000000000
[60103.826197] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[60103.826200] CR2: ffff9641f2004000 CR3: 0000000013b0c000 CR4: 00000000000006f0
[60103.826204] Call Trace:
[60103.826212] <IRQ>
[60103.826225] cdc_ncm_fill_tx_frame+0x5e3/0x740 [cdc_ncm]
[60103.826236] cdc_ncm_tx_fixup+0x57/0x70 [cdc_ncm]
[60103.826246] usbnet_start_xmit+0x5d/0x710 [usbnet]
[60103.826254] ? netif_skb_features+0x119/0x250
[60103.826259] dev_hard_start_xmit+0xa1/0x200
[60103.826267] sch_direct_xmit+0xf2/0x1b0
[60103.826273] __dev_queue_xmit+0x5e3/0x7c0
[60103.826280] ? ip_finish_output2+0x263/0x3c0
[60103.826284] ip_finish_output2+0x263/0x3c0
[60103.826289] ? ip_output+0x6c/0xe0
[60103.826293] ip_output+0x6c/0xe0
[60103.826298] ? ip_forward_options+0x1a0/0x1a0
[60103.826303] tcp_transmit_skb+0x516/0x9b0
[60103.826309] tcp_write_xmit+0x1aa/0xee0
[60103.826313] ? sch_direct_xmit+0x71/0x1b0
[60103.826318] tcp_tasklet_func+0x177/0x180
[60103.826325] tasklet_action+0x5f/0x110
[60103.826332] __do_softirq+0xde/0x2b3
[60103.826337] irq_exit+0xae/0xb0
[60103.826342] do_IRQ+0x81/0xd0
[60103.826347] common_interrupt+0x98/0x98
[60103.826351] </IRQ>
[60103.826355] RIP: 0033:0x7f397bdf2282
[60103.826358] RSP: 002b:00007f395aaf57d8 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff6e
[60103.826362] RAX: 0000000000000000 RBX: 00002f07bc6d0900 RCX: 00007f39752d7fe7
[60103.826365] RDX: 0000000000000022 RSI: 0000000000000147 RDI: 00002f07baea02c0
[60103.826368] RBP: 0000000000000001 R08: 0000000000000000 R09: 0000000000000000
[60103.826371] R10: 00000000ffffffff R11: 0000000000000000 R12: 00002f07baea02c0
[60103.826373] R13: 00002f07bba227a0 R14: 00002f07bc6d090c R15: 0000000000000000
[60103.826377] Code: 90 90 90 90 90 90 90 0f 1f 44 00 00 49 89 f9 48 89 d1 83
e2 07 48 c1 e9 03 40 0f b6 f6 48 b8 01 01 01 01 01 01 01 01 48 0f af c6 <f3> 48
ab 89 d1 f3 aa 4c 89 c8 c3 90 49 89 f9 40 88 f0 48 89 d1
[60103.826442] RIP: __memset+0x24/0x30 RSP: ffff964316c03b68
[60103.826444] CR2: ffff9641f2004000
Commit e1069bbfcf3b ("net: cdc_ncm: Reduce memory use when kernel
memory low") made this bug much more likely to trigger by reducing
the NTB size under memory pressure.
Link: https://bugs.debian.org/893393
Reported-by: Горбешко Богдан <bodqhrohro@gmail.com>
Reported-and-tested-by: Dennis Wassenberg <dennis.wassenberg@secunet.com>
Cc: Enrico Mioso <mrkiko.rs@gmail.com>
Fixes: 4a0e3e989d66 ("cdc_ncm: Add support for moving NDP to end of NCM frame")
Signed-off-by: Bjørn Mork <bjorn@mork.no>
Signed-off-by: David S. Miller <davem@davemloft.net>
use nla_strlcpy() to avoid copying data beyond the length of TCA_DEF_DATA
netlink attribute, in case it is less than SIMP_MAX_DATA and it does not
end with '\0' character.
v2: fix errors in the commit message, thanks Hangbin Liu
Fixes: fa1b1cff3d06 ("net_cls_act: Make act_simple use of netlink policy.")
Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Simon Horman <simon.horman@netronome.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
bp->SharedMemAddr is set to NULL while bp->SharedMemSize lesser-or-equal 0,
then memset will trigger null-ptr-deref.
fix it by replacing pci_alloc_consistent with dma_zalloc_coherent.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
From: Colin Ian King <colin.king@canonical.com>
This was originally mistakenly submitted to net-next. Resubmitting to net.
The comparison of numvecs < 0 is always false because numvecs is a u32
and hence the error return from a failed call to pci_alloc_irq_vectores
is never detected. Fix this by using the signed int ret to handle the
error return and assign numvecs to err.
Detected by CoverityScan, CID#1468650 ("Unsigned compared against 0")
Fixes: a09bd81b5413 ("net: aquantia: Limit number of vectors to actually allocated irqs")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Igor Russkikh <igor.russkikh@aquantia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch fix the build failure on m68k;
drivers/net/ethernet/stmicro/stmmac/dwmac-ipq806x.o: In function `ipq806x_gmac_probe':
dwmac-ipq806x.c:(.text+0xda): undefined reference to `clk_set_rate'
drivers/net/ethernet/stmicro/stmmac/dwmac-rk.o: In function `rk_gmac_probe':
dwmac-rk.c:(.text+0x1e58): undefined reference to `clk_set_rate'
drivers/net/ethernet/stmicro/stmmac/dwmac-sti.o: In function `stid127_fix_retime_src':
dwmac-sti.c:(.text+0xd8): undefined reference to `clk_set_rate'
dwmac-sti.c:(.text+0x114): undefined reference to `clk_set_rate'
drivers/net/ethernet/stmicro/stmmac/dwmac-sti.o:dwmac-sti.c:(.text+0x12c): more undefined references to `clk_set_rate' follow
Lots of stmmac platform drivers need COMMON_CLK in their Kconfig depends.
Signed-off-by: Corentin Labbe <clabbe@baylibre.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
syzbot reported the following crash
[ 338.293946] bpfilter: read fail -512
[ 338.304515] kasan: GPF could be caused by NULL-ptr deref or user memory access
[ 338.311863] general protection fault: 0000 [#1] SMP KASAN
[ 338.344360] RIP: 0010:__vfs_write+0x4a6/0x960
[ 338.426363] Call Trace:
[ 338.456967] __kernel_write+0x10c/0x380
[ 338.460928] __bpfilter_process_sockopt+0x1d8/0x35b
[ 338.487103] bpfilter_mbox_request+0x4d/0xb0
[ 338.491492] bpfilter_ip_get_sockopt+0x6b/0x90
This can happen when multiple cpus trying to talk to user mode process
via bpfilter_mbox_request(). One cpu grabs the mutex while another goes to
sleep on the same mutex. Then former cpu sees that umh pipe is down and
shuts down the pipes. Later cpu finally acquires the mutex and crashes
on freed pipe.
Fix the race by using info.pid as an indicator that umh and pipes are healthy
and check it after acquiring the mutex.
Fixes: d2ba09c17a06 ("net: add skeleton of bpfilter kernel module")
Reported-by: syzbot+7ade6c94abb2774c0fee@syzkaller.appspotmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf 2018-06-08
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix in the BPF verifier to reject modified ctx pointers on helper
functions, from Daniel.
2) Fix in BPF kselftests for get_cgroup_id_user() helper to only
record the cgroup id for a provided pid in order to reduce test
failures from processes interferring with the test, from Yonghong.
3) Fix a crash in AF_XDP's mem accounting when the process owning
the sock has CAP_IPC_LOCK capabilities set, from Daniel.
4) Fix an issue for AF_XDP on 32 bit machines where XDP_UMEM_PGOFF_*_RING
defines need ULL suffixes and use loff_t type as they are otherwise
truncated, from Geert.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
CONFIG_OUTPUT_FORMAT is x86 only macro.
Used objdump to extract elf file format.
Fixes: d2ba09c17a06 ("net: add skeleton of bpfilter kernel module")
Reported-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
syzkaller was able to trigger the following panic for AF_XDP:
BUG: KASAN: null-ptr-deref in atomic64_sub include/asm-generic/atomic-instrumented.h:144 [inline]
BUG: KASAN: null-ptr-deref in atomic_long_sub include/asm-generic/atomic-long.h:199 [inline]
BUG: KASAN: null-ptr-deref in xdp_umem_unaccount_pages.isra.4+0x3d/0x80 net/xdp/xdp_umem.c:135
Write of size 8 at addr 0000000000000060 by task syz-executor246/4527
CPU: 1 PID: 4527 Comm: syz-executor246 Not tainted 4.17.0+ #89
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x1b9/0x294 lib/dump_stack.c:113
kasan_report_error mm/kasan/report.c:352 [inline]
kasan_report.cold.7+0x6d/0x2fe mm/kasan/report.c:412
check_memory_region_inline mm/kasan/kasan.c:260 [inline]
check_memory_region+0x13e/0x1b0 mm/kasan/kasan.c:267
kasan_check_write+0x14/0x20 mm/kasan/kasan.c:278
atomic64_sub include/asm-generic/atomic-instrumented.h:144 [inline]
atomic_long_sub include/asm-generic/atomic-long.h:199 [inline]
xdp_umem_unaccount_pages.isra.4+0x3d/0x80 net/xdp/xdp_umem.c:135
xdp_umem_reg net/xdp/xdp_umem.c:334 [inline]
xdp_umem_create+0xd6c/0x10f0 net/xdp/xdp_umem.c:349
xsk_setsockopt+0x443/0x550 net/xdp/xsk.c:531
__sys_setsockopt+0x1bd/0x390 net/socket.c:1935
__do_sys_setsockopt net/socket.c:1946 [inline]
__se_sys_setsockopt net/socket.c:1943 [inline]
__x64_sys_setsockopt+0xbe/0x150 net/socket.c:1943
do_syscall_64+0x1b1/0x800 arch/x86/entry/common.c:287
entry_SYSCALL_64_after_hwframe+0x49/0xbe
In xdp_umem_reg() the call to xdp_umem_account_pages() passed
with CAP_IPC_LOCK where we didn't need to end up charging rlimit
on memlock for the current user and therefore umem->user continues
to be NULL. Later on through fault injection syzkaller triggered
a failure in either umem->pgs or umem->pages allocation such that
we bail out and undo accounting in xdp_umem_unaccount_pages()
where we eventually hit the panic since it tries to deref the
umem->user.
The code is pretty close to mm_account_pinned_pages() and
mm_unaccount_pinned_pages() pair and potentially could reuse
it even in a later cleanup, and it appears that the initial
commit c0c77d8fb787 ("xsk: add user memory registration support
sockopt") got this right while later follow-up introduced the
bug via a49049ea2576 ("xsk: simplified umem setup").
Fixes: a49049ea2576 ("xsk: simplified umem setup")
Reported-by: syzbot+979217770b09ebf5c407@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
README