diff options
| author | Paolo Abeni <pabeni@redhat.com> | 2021-03-05 00:32:10 +0300 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2021-03-05 01:30:13 +0300 |
| commit | eaeef1ce55ec9161e0c44ff27017777b1644b421 (patch) | |
| tree | f69dbae2e189f004241b02c9086ad2c678293764 | |
| parent | f07157792c633b528de5fc1dbe2e4ea54f8e09d4 (diff) | |
| download | linux-eaeef1ce55ec9161e0c44ff27017777b1644b421.tar.xz | |
mptcp: fix memory accounting on allocation error
In case of memory pressure the MPTCP xmit path keeps
at most a single skb in the tx cache, eventually freeing
additional ones.
The associated counter for forward memory is not update
accordingly, and that causes the following splat:
WARNING: CPU: 0 PID: 12 at net/core/stream.c:208 sk_stream_kill_queues+0x3ca/0x530 net/core/stream.c:208
Modules linked in:
CPU: 0 PID: 12 Comm: kworker/0:1 Not tainted 5.11.0-rc2 #59
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
Workqueue: events mptcp_worker
RIP: 0010:sk_stream_kill_queues+0x3ca/0x530 net/core/stream.c:208
Code: 03 0f b6 04 02 84 c0 74 08 3c 03 0f 8e 63 01 00 00 8b ab 00 01 00 00 e9 60 ff ff ff e8 2f 24 d3 fe 0f 0b eb 97 e8 26 24 d3 fe <0f> 0b eb a0 e8 1d 24 d3 fe 0f 0b e9 a5 fe ff ff 4c 89 e7 e8 0e d0
RSP: 0018:ffffc900000c7bc8 EFLAGS: 00010293
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88810030ac40 RSI: ffffffff8262ca4a RDI: 0000000000000003
RBP: 0000000000000d00 R08: 0000000000000000 R09: ffffffff85095aa7
R10: ffffffff8262c9ea R11: 0000000000000001 R12: ffff888108908100
R13: ffffffff85095aa0 R14: ffffc900000c7c48 R15: 1ffff92000018f85
FS: 0000000000000000(0000) GS:ffff88811b200000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fa7444baef8 CR3: 0000000035ee9005 CR4: 0000000000170ef0
Call Trace:
__mptcp_destroy_sock+0x4a7/0x6c0 net/mptcp/protocol.c:2547
mptcp_worker+0x7dd/0x1610 net/mptcp/protocol.c:2272
process_one_work+0x896/0x1170 kernel/workqueue.c:2275
worker_thread+0x605/0x1350 kernel/workqueue.c:2421
kthread+0x344/0x410 kernel/kthread.c:292
ret_from_fork+0x22/0x30 arch/x86/entry/entry_64.S:296
At close time, as reported by syzkaller/Christoph.
This change address the issue properly updating the fwd
allocated memory counter in the error path.
Reported-by: Christoph Paasch <cpaasch@apple.com>
Closes: https://github.com/multipath-tcp/mptcp_net-next/issues/136
Fixes: 724cfd2ee8aa ("mptcp: allocate TX skbs in msk context")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
| -rw-r--r-- | net/mptcp/protocol.c | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/net/mptcp/protocol.c b/net/mptcp/protocol.c index 7362a536cbc0..aa59101ffe54 100644 --- a/net/mptcp/protocol.c +++ b/net/mptcp/protocol.c @@ -1189,6 +1189,7 @@ static bool mptcp_tx_cache_refill(struct sock *sk, int size, */ while (skbs->qlen > 1) { skb = __skb_dequeue_tail(skbs); + *total_ts -= skb->truesize; __kfree_skb(skb); } return skbs->qlen > 0; |