[syzbot] [io-uring?] KMSAN: uninit-value in io_sendrecv_fail

syzbot
2024-03-15T22:28:16Z

Hello,

syzbot found the following issue on:

HEAD commit: 8ede842f669b Merge tag 'rust-6.9' of https://github.com/Ru..
git tree: upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=138f0ad6180000
kernel config: https://syzkaller.appspot.com/x/.config?x=a271c5dca0ff14df
dashboard link: https://syzkaller.appspot.com/bug?extid=f8e9a371388aa62ecab4
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=15b4a6fa180000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=14a59799180000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/af1cd47b84ef/disk-8ede842f.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/be9297712c37/vmlinux-8ede842f.xz
kernel image: https://storage.googleapis.com/syzbot-assets/c569fb33468d/bzImage-8ede842f.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f8e9a371388aa62ecab4@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in io_sendrecv_fail+0x91/0x1e0 io_uring/net.c:1334
io_sendrecv_fail+0x91/0x1e0 io_uring/net.c:1334
io_req_defer_failed+0x3bd/0x610 io_uring/io_uring.c:1050
io_queue_sqe_fallback+0x1e3/0x280 io_uring/io_uring.c:2126
io_submit_fail_init+0x4e1/0x790 io_uring/io_uring.c:2304
io_submit_sqes+0x19cd/0x2fb0 io_uring/io_uring.c:2480
__do_sys_io_uring_enter io_uring/io_uring.c:3656 [inline]
__se_sys_io_uring_enter+0x409/0x43e0 io_uring/io_uring.c:3591
__x64_sys_io_uring_enter+0x11b/0x1a0 io_uring/io_uring.c:3591
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

Uninit was created at:
__alloc_pages+0x9a6/0xe00 mm/page_alloc.c:4592
__alloc_pages_node include/linux/gfp.h:238 [inline]
alloc_pages_node include/linux/gfp.h:261 [inline]
alloc_slab_page mm/slub.c:2190 [inline]
allocate_slab mm/slub.c:2354 [inline]
new_slab+0x2d7/0x1400 mm/slub.c:2407
___slab_alloc+0x16b5/0x3970 mm/slub.c:3540
__kmem_cache_alloc_bulk mm/slub.c:4574 [inline]
kmem_cache_alloc_bulk+0x52a/0x1440 mm/slub.c:4648
__io_alloc_req_refill+0x248/0x780 io_uring/io_uring.c:1101
io_alloc_req io_uring/io_uring.h:405 [inline]
io_submit_sqes+0xaa1/0x2fb0 io_uring/io_uring.c:2469
__do_sys_io_uring_enter io_uring/io_uring.c:3656 [inline]
__se_sys_io_uring_enter+0x409/0x43e0 io_uring/io_uring.c:3591
__x64_sys_io_uring_enter+0x11b/0x1a0 io_uring/io_uring.c:3591
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcf/0x1e0 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x63/0x6b

CPU: 1 PID: 5021 Comm: syz-executor425 Not tainted 6.8.0-syzkaller-00648-g8ede842f669b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/29/2024
=====================================================

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