[syzbot] memory leak in create_io_worker (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 7993e65fdd0f Merge tag 'mtd/fixes-for-5.17-rc5' of git://g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=12b8d5bc700000
kernel config: https://syzkaller.appspot.com/x/.config?x=6668288739b7ad26
dashboard link: https://syzkaller.appspot.com/bug?extid=7085977fe51df63eb2bf
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=17eae25a700000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=17a51236700000

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+708597...@syzkaller.appspotmail.com

executing program
executing program
executing program
executing program
executing program
BUG: memory leak
unreferenced object 0xffff888112ec56c0 (size 192):
comm "syz-executor313", pid 30410, jiffies 4294958360 (age 18.100s)
hex dump (first 32 bytes):
01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:
[<ffffffff816515c6>] kmalloc_node include/linux/slab.h:599 [inline]
[<ffffffff816515c6>] kzalloc_node include/linux/slab.h:726 [inline]
[<ffffffff816515c6>] create_io_worker+0x46/0x250 fs/io-wq.c:812
[<ffffffff81652ab2>] create_worker_cb+0xd2/0xf0 fs/io-wq.c:331
[<ffffffff81273853>] task_work_run+0x73/0xb0 kernel/task_work.c:164
[<ffffffff8163dadd>] tracehook_notify_signal include/linux/tracehook.h:213 [inline]
[<ffffffff8163dadd>] io_run_task_work fs/io_uring.c:2595 [inline]
[<ffffffff8163dadd>] io_run_task_work fs/io_uring.c:2591 [inline]
[<ffffffff8163dadd>] io_run_task_work_sig+0x6d/0x110 fs/io_uring.c:7684
[<ffffffff8164ec75>] io_cqring_wait_schedule fs/io_uring.c:7701 [inline]
[<ffffffff8164ec75>] io_cqring_wait fs/io_uring.c:7770 [inline]
[<ffffffff8164ec75>] __do_sys_io_uring_enter+0x715/0xf60 fs/io_uring.c:10178
[<ffffffff844b4875>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff844b4875>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff84600068>] entry_SYSCALL_64_after_hwframe+0x44/0xae



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[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
memory leak in create_io_worker

BUG: memory leak
unreferenced object 0xffff8881123fbcc0 (size 192):
comm "syz-executor238", pid 4085, jiffies 4294944016 (age 14.560s)

hex dump (first 32 bytes):
01 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
backtrace:

[<ffffffff8164b416>] kmalloc_node include/linux/slab.h:599 [inline]
[<ffffffff8164b416>] kzalloc_node include/linux/slab.h:725 [inline]
[<ffffffff8164b416>] create_io_worker+0x46/0x250 fs/io-wq.c:812
[<ffffffff8164c902>] create_worker_cb+0xd2/0xf0 fs/io-wq.c:331
[<ffffffff81270253>] task_work_run+0x73/0xb0 kernel/task_work.c:164
[<ffffffff81638c0d>] tracehook_notify_signal include/linux/tracehook.h:213 [inline]
[<ffffffff81638c0d>] io_run_task_work fs/io_uring.c:2595 [inline]
[<ffffffff81638c0d>] io_run_task_work fs/io_uring.c:2591 [inline]
[<ffffffff81638c0d>] io_run_task_work_sig+0x6d/0x110 fs/io_uring.c:7685
[<ffffffff81648acd>] io_cqring_wait_schedule fs/io_uring.c:7702 [inline]
[<ffffffff81648acd>] io_cqring_wait fs/io_uring.c:7772 [inline]
[<ffffffff81648acd>] __do_sys_io_uring_enter+0x77d/0xfc0 fs/io_uring.c:10188
[<ffffffff844929f5>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff844929f5>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
[<ffffffff84600068>] entry_SYSCALL_64_after_hwframe+0x44/0xae



Tested on:

commit: fb184c4a Merge tag 'for-linus' of git://git.kernel.org..
git tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
console output: https://syzkaller.appspot.com/x/log.txt?x=15490592700000
kernel config: https://syzkaller.appspot.com/x/.config?x=1d43b139ddee0120

dashboard link: https://syzkaller.appspot.com/bug?extid=7085977fe51df63eb2bf
compiler: gcc (Debian 10.2.1-6) 10.2.1 20210110, GNU ld (GNU Binutils for Debian) 2.35.2

Note: no patches were applied.

[syzbot]

Auto-closing this bug as obsolete.
No recent activity, existing reproducers are no longer triggering the issue.