[syzbot] [io-uring?] KMSAN: uninit-value in io_req_cqe_overflow (3)

[syzbot <syzbot+e6616d0dc8ded5dc56d6@syzkaller.appspotmail.com>]

Hello,

syzbot found the following issue on:

HEAD commit:    614da38e2f7a Merge tag 'hid-for-linus-2024051401' of git:/..
git tree:       upstream
console+strace: https://syzkaller.appspot.com/x/log.txt?x=12980e41980000
kernel config:  https://syzkaller.appspot.com/x/.config?x=f5d2cbf33633f507
dashboard link: https://syzkaller.appspot.com/bug?extid=e6616d0dc8ded5dc56d6
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=13526ca2980000
C reproducer:   https://syzkaller.appspot.com/x/repro.c?x=144e5256980000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/89eafb874b71/disk-614da38e.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/356000512ad9/vmlinux-614da38e.xz
kernel image: https://storage.googleapis.com/syzbot-assets/839c73939115/bzImage-614da38e.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+e6616d0dc8ded5dc56d6@syzkaller.appspotmail.com

=====================================================
BUG: KMSAN: uninit-value in io_req_cqe_overflow+0x193/0x1c0 io_uring/io_uring.c:810
 io_req_cqe_overflow+0x193/0x1c0 io_uring/io_uring.c:810
 __io_submit_flush_completions+0x7eb/0x1be0 io_uring/io_uring.c:1464
 io_submit_flush_completions io_uring/io_uring.h:148 [inline]
 ctx_flush_and_put+0x16c/0x360 io_uring/io_uring.c:1055
 io_handle_tw_list+0x58b/0x5c0 io_uring/io_uring.c:1095
 tctx_task_work_run+0xf8/0x3d0 io_uring/io_uring.c:1155
 tctx_task_work+0x6d/0xc0 io_uring/io_uring.c:1173
 task_work_run+0x268/0x310 kernel/task_work.c:180
 ptrace_notify+0x304/0x320 kernel/signal.c:2404
 ptrace_report_syscall include/linux/ptrace.h:415 [inline]
 ptrace_report_syscall_exit include/linux/ptrace.h:477 [inline]
 syscall_exit_work+0x14e/0x3e0 kernel/entry/common.c:173
 syscall_exit_to_user_mode_prepare kernel/entry/common.c:200 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:205 [inline]
 syscall_exit_to_user_mode+0x135/0x160 kernel/entry/common.c:218
 do_syscall_64+0xdc/0x1e0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was stored to memory at:
 io_req_set_res io_uring/io_uring.h:215 [inline]
 io_recv_finish+0xf10/0x1560 io_uring/net.c:861
 io_recv+0x12ec/0x1ea0 io_uring/net.c:1175
 io_issue_sqe+0x429/0x22c0 io_uring/io_uring.c:1751
 io_poll_issue+0x32/0x40 io_uring/io_uring.c:1782
 io_poll_check_events io_uring/poll.c:331 [inline]
 io_poll_task_func+0x5f9/0x14d0 io_uring/poll.c:357
 io_handle_tw_list+0x23a/0x5c0 io_uring/io_uring.c:1083
 tctx_task_work_run+0xf8/0x3d0 io_uring/io_uring.c:1155
 tctx_task_work+0x6d/0xc0 io_uring/io_uring.c:1173
 task_work_run+0x268/0x310 kernel/task_work.c:180
 ptrace_notify+0x304/0x320 kernel/signal.c:2404
 ptrace_report_syscall include/linux/ptrace.h:415 [inline]
 ptrace_report_syscall_exit include/linux/ptrace.h:477 [inline]
 syscall_exit_work+0x14e/0x3e0 kernel/entry/common.c:173
 syscall_exit_to_user_mode_prepare kernel/entry/common.c:200 [inline]
 __syscall_exit_to_user_mode_work kernel/entry/common.c:205 [inline]
 syscall_exit_to_user_mode+0x135/0x160 kernel/entry/common.c:218
 do_syscall_64+0xdc/0x1e0 arch/x86/entry/common.c:89
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Uninit was created at:
 slab_post_alloc_hook mm/slub.c:3877 [inline]
 slab_alloc_node mm/slub.c:3918 [inline]
 __do_kmalloc_node mm/slub.c:4038 [inline]
 __kmalloc+0x6e4/0x1060 mm/slub.c:4052
 kmalloc include/linux/slab.h:632 [inline]
 io_alloc_async_data+0xc0/0x220 io_uring/io_uring.c:1662
 io_msg_alloc_async io_uring/net.c:166 [inline]
 io_recvmsg_prep_setup io_uring/net.c:725 [inline]
 io_recvmsg_prep+0xbe8/0x1a20 io_uring/net.c:806
 io_init_req io_uring/io_uring.c:2135 [inline]
 io_submit_sqe io_uring/io_uring.c:2182 [inline]
 io_submit_sqes+0x1135/0x2f10 io_uring/io_uring.c:2335
 __do_sys_io_uring_enter io_uring/io_uring.c:3246 [inline]
 __se_sys_io_uring_enter+0x40f/0x3c80 io_uring/io_uring.c:3183
 __x64_sys_io_uring_enter+0x11f/0x1a0 io_uring/io_uring.c:3183
 x64_sys_call+0x2c0/0x3b50 arch/x86/include/generated/asm/syscalls_64.h:427
 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+0x77/0x7f

CPU: 1 PID: 5049 Comm: syz-executor107 Not tainted 6.9.0-syzkaller-02707-g614da38e2f7a #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
=====================================================


---
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