The patch below does not apply to the 6.1-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable@xxxxxxxxxxxxxxx>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.1.y git checkout FETCH_HEAD git cherry-pick -x 78fbb92af27d0982634116c7a31065f24d092826 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable@xxxxxxxxxxxxxxx>' --in-reply-to '2024012655-dwelled-unlinked-8b2c@gregkh' --subject-prefix 'PATCH 6.1.y' HEAD^.. Possible dependencies: 78fbb92af27d ("nbd: always initialize struct msghdr completely") 98123866fcf3 ("Treewide: Stop corrupting socket's task_frag") c3d88dfd1583 ("fs: dlm: cleanup listen sock handling") 4f567acb0b86 ("fs: dlm: remove socket shutdown handling") 1037c2a94ab5 ("fs: dlm: use listen sock as dlm running indicator") 08ae0547e75e ("fs: dlm: fix sock release if listen fails") thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 78fbb92af27d0982634116c7a31065f24d092826 Mon Sep 17 00:00:00 2001 From: Eric Dumazet <edumazet@xxxxxxxxxx> Date: Fri, 12 Jan 2024 13:26:57 +0000 Subject: [PATCH] nbd: always initialize struct msghdr completely syzbot complains that msg->msg_get_inq value can be uninitialized [1] struct msghdr got many new fields recently, we should always make sure their values is zero by default. [1] BUG: KMSAN: uninit-value in tcp_recvmsg+0x686/0xac0 net/ipv4/tcp.c:2571 tcp_recvmsg+0x686/0xac0 net/ipv4/tcp.c:2571 inet_recvmsg+0x131/0x580 net/ipv4/af_inet.c:879 sock_recvmsg_nosec net/socket.c:1044 [inline] sock_recvmsg+0x12b/0x1e0 net/socket.c:1066 __sock_xmit+0x236/0x5c0 drivers/block/nbd.c:538 nbd_read_reply drivers/block/nbd.c:732 [inline] recv_work+0x262/0x3100 drivers/block/nbd.c:863 process_one_work kernel/workqueue.c:2627 [inline] process_scheduled_works+0x104e/0x1e70 kernel/workqueue.c:2700 worker_thread+0xf45/0x1490 kernel/workqueue.c:2781 kthread+0x3ed/0x540 kernel/kthread.c:388 ret_from_fork+0x66/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:242 Local variable msg created at: __sock_xmit+0x4c/0x5c0 drivers/block/nbd.c:513 nbd_read_reply drivers/block/nbd.c:732 [inline] recv_work+0x262/0x3100 drivers/block/nbd.c:863 CPU: 1 PID: 7465 Comm: kworker/u5:1 Not tainted 6.7.0-rc7-syzkaller-00041-gf016f7547aee #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 11/17/2023 Workqueue: nbd5-recv recv_work Fixes: f94fd25cb0aa ("tcp: pass back data left in socket after receive") Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx> Signed-off-by: Eric Dumazet <edumazet@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Cc: Josef Bacik <josef@xxxxxxxxxxxxxx> Cc: Jens Axboe <axboe@xxxxxxxxx> Cc: linux-block@xxxxxxxxxxxxxxx Cc: nbd@xxxxxxxxxxxxxxxx Reviewed-by: Simon Horman <horms@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240112132657.647112-1-edumazet@xxxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c index 4e72ec4e25ac..33a8f37bb6a1 100644 --- a/drivers/block/nbd.c +++ b/drivers/block/nbd.c @@ -508,7 +508,7 @@ static int __sock_xmit(struct nbd_device *nbd, struct socket *sock, int send, struct iov_iter *iter, int msg_flags, int *sent) { int result; - struct msghdr msg; + struct msghdr msg = {} ; unsigned int noreclaim_flag; if (unlikely(!sock)) { @@ -524,10 +524,6 @@ static int __sock_xmit(struct nbd_device *nbd, struct socket *sock, int send, do { sock->sk->sk_allocation = GFP_NOIO | __GFP_MEMALLOC; sock->sk->sk_use_task_frag = false; - msg.msg_name = NULL; - msg.msg_namelen = 0; - msg.msg_control = NULL; - msg.msg_controllen = 0; msg.msg_flags = msg_flags | MSG_NOSIGNAL; if (send)
