net/tls: Fix skb memory leak when running kTLS traffic
The cited Fixes commit introduced a memory leak when running kTLS
traffic (with/without hardware offloads).
I'm running nginx on the server side and wrk on the client side and get
the following:
unreferenced object 0xffff8881935e9b80 (size 224):
comm "softirq", pid 0, jiffies 4294903611 (age 43.204s)
hex dump (first 32 bytes):
80 9b d0 36 81 88 ff ff 00 00 00 00 00 00 00 00 ...6............
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<00000000efe2a999>] build_skb+0x1f/0x170
[<00000000ef521785>] mlx5e_skb_from_cqe_mpwrq_linear+0x2bc/0x610 [mlx5_core]
[<00000000945d0ffe>] mlx5e_handle_rx_cqe_mpwrq+0x264/0x9e0 [mlx5_core]
[<00000000cb675b06>] mlx5e_poll_rx_cq+0x3ad/0x17a0 [mlx5_core]
[<0000000018aac6a9>] mlx5e_napi_poll+0x28c/0x1b60 [mlx5_core]
[<000000001f3369d1>] __napi_poll+0x9f/0x560
[<00000000cfa11f72>] net_rx_action+0x357/0xa60
[<000000008653b8d7>] __do_softirq+0x282/0x94e
[<00000000644923c6>] __irq_exit_rcu+0x11f/0x170
[<00000000d4085f8f>] irq_exit_rcu+0xa/0x20
[<00000000d412fef4>] common_interrupt+0x7d/0xa0
[<00000000bfb0cebc>] asm_common_interrupt+0x1e/0x40
[<00000000d80d0890>] default_idle+0x53/0x70
[<00000000f2b9780e>] default_idle_call+0x8c/0xd0
[<00000000c7659e15>] do_idle+0x394/0x450
I'm not familiar with these areas of the code, but I've added this
sk_defer_free_flush() to tls_sw_recvmsg() based on a hunch and it
resolved the issue.
Fixes: f35f821935d8 ("tcp: defer skb freeing after socket lock is released")
Signed-off-by: Gal Pressman <gal@nvidia.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20220102081253.9123-1-gal@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
1 file changed