Liu Jian wrote:
> Fix one kernel NULL pointer dereference as below:
>
> [ 224.462334] Call Trace:
> [ 224.462394] __tcp_bpf_recvmsg+0xd3/0x380
> [ 224.462441] ? sock_has_perm+0x78/0xa0
> [ 224.462463] tcp_bpf_recvmsg+0x12e/0x220
> [ 224.462494] inet_recvmsg+0x5b/0xd0
> [ 224.462534] __sys_recvfrom+0xc8/0x130
> [ 224.462574] ? syscall_trace_enter+0x1df/0x2e0
> [ 224.462606] ? __do_page_fault+0x2de/0x500
> [ 224.462635] __x64_sys_recvfrom+0x24/0x30
> [ 224.462660] do_syscall_64+0x5d/0x1d0
> [ 224.462709] entry_SYSCALL_64_after_hwframe+0x65/0xca
>
> In commit 9974d37ea75f ("skmsg: Fix invalid last sg check in
> sk_msg_recvmsg()"), we change last sg check to sg_is_last(),
> but in sockmap redirection case (without stream_parser/stream_verdict/
> skb_verdict), we did not mark the end of the scatterlist. Check the
> sk_msg_alloc, sk_msg_page_add, and bpf_msg_push_data functions, they all
> do not mark the end of sg. They are expected to use sg.end for end
> judgment. So the judgment of '(i != msg_rx->sg.end)' is added back here.
>
> Fixes: 9974d37ea75f ("skmsg: Fix invalid last sg check in sk_msg_recvmsg()")
> Signed-off-by: Liu Jian <liujian56@xxxxxxxxxx>
> ---
OK lets take this. Thanks.
Acked-by: John Fastabend <john.fastabend@xxxxxxxxx>
