| Message ID | 20230214012606.5804-1-tung.q.nguyen@dektech.com.au (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 11a4d6f67cf55883dc78e31c247d1903ed7feccc |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [v3,net,1/1] tipc: fix kernel warning when sending SYN message | expand |
Hello: This patch was applied to netdev/net.git (master) by Jakub Kicinski <kuba@kernel.org>: On Tue, 14 Feb 2023 01:26:06 +0000 you wrote: > When sending a SYN message, this kernel stack trace is observed: > > ... > [ 13.396352] RIP: 0010:_copy_from_iter+0xb4/0x550 > ... > [ 13.398494] Call Trace: > [ 13.398630] <TASK> > [ 13.398630] ? __alloc_skb+0xed/0x1a0 > [ 13.398630] tipc_msg_build+0x12c/0x670 [tipc] > [ 13.398630] ? shmem_add_to_page_cache.isra.71+0x151/0x290 > [ 13.398630] __tipc_sendmsg+0x2d1/0x710 [tipc] > [ 13.398630] ? tipc_connect+0x1d9/0x230 [tipc] > [ 13.398630] ? __local_bh_enable_ip+0x37/0x80 > [ 13.398630] tipc_connect+0x1d9/0x230 [tipc] > [ 13.398630] ? __sys_connect+0x9f/0xd0 > [ 13.398630] __sys_connect+0x9f/0xd0 > [ 13.398630] ? preempt_count_add+0x4d/0xa0 > [ 13.398630] ? fpregs_assert_state_consistent+0x22/0x50 > [ 13.398630] __x64_sys_connect+0x16/0x20 > [ 13.398630] do_syscall_64+0x42/0x90 > [ 13.398630] entry_SYSCALL_64_after_hwframe+0x63/0xcd > > [...] Here is the summary with links: - [v3,net,1/1] tipc: fix kernel warning when sending SYN message https://git.kernel.org/netdev/net/c/11a4d6f67cf5 You are awesome, thank you!
diff --git a/net/tipc/socket.c b/net/tipc/socket.c index b35c8701876a..a38733f2197a 100644 --- a/net/tipc/socket.c +++ b/net/tipc/socket.c @@ -2614,6 +2614,7 @@ static int tipc_connect(struct socket *sock, struct sockaddr *dest, /* Send a 'SYN-' to destination */ m.msg_name = dest; m.msg_namelen = destlen; + iov_iter_kvec(&m.msg_iter, ITER_SOURCE, NULL, 0, 0); /* If connect is in non-blocking case, set MSG_DONTWAIT to * indicate send_msg() is never blocked. @@ -2776,6 +2777,7 @@ static int tipc_accept(struct socket *sock, struct socket *new_sock, int flags, __skb_queue_head(&new_sk->sk_receive_queue, buf); skb_set_owner_r(buf, new_sk); } + iov_iter_kvec(&m.msg_iter, ITER_SOURCE, NULL, 0, 0); __tipc_sendstream(new_sock, &m, 0); release_sock(new_sk); exit:
When sending a SYN message, this kernel stack trace is observed: ... [ 13.396352] RIP: 0010:_copy_from_iter+0xb4/0x550 ... [ 13.398494] Call Trace: [ 13.398630] <TASK> [ 13.398630] ? __alloc_skb+0xed/0x1a0 [ 13.398630] tipc_msg_build+0x12c/0x670 [tipc] [ 13.398630] ? shmem_add_to_page_cache.isra.71+0x151/0x290 [ 13.398630] __tipc_sendmsg+0x2d1/0x710 [tipc] [ 13.398630] ? tipc_connect+0x1d9/0x230 [tipc] [ 13.398630] ? __local_bh_enable_ip+0x37/0x80 [ 13.398630] tipc_connect+0x1d9/0x230 [tipc] [ 13.398630] ? __sys_connect+0x9f/0xd0 [ 13.398630] __sys_connect+0x9f/0xd0 [ 13.398630] ? preempt_count_add+0x4d/0xa0 [ 13.398630] ? fpregs_assert_state_consistent+0x22/0x50 [ 13.398630] __x64_sys_connect+0x16/0x20 [ 13.398630] do_syscall_64+0x42/0x90 [ 13.398630] entry_SYSCALL_64_after_hwframe+0x63/0xcd It is because commit a41dad905e5a ("iov_iter: saner checks for attempt to copy to/from iterator") has introduced sanity check for copying from/to iov iterator. Lacking of copy direction from the iterator viewpoint would lead to kernel stack trace like above. This commit fixes this issue by initializing the iov iterator with the correct copy direction when sending SYN or ACK without data. Fixes: f25dcc7687d4 ("tipc: tipc ->sendmsg() conversion") Reported-by: syzbot+d43608d061e8847ec9f3@syzkaller.appspotmail.com Acked-by: Jon Maloy <jmaloy@redhat.com> Signed-off-by: Tung Nguyen <tung.q.nguyen@dektech.com.au> --- v3: adapt to Paolo and Jakub's comments net/tipc/socket.c | 2 ++ 1 file changed, 2 insertions(+)