syzbot


WARNING in mntput_no_expire (3)
Status: upstream: reported C repro on 2021/11/15 22:27
Reported-by: syzbot+5b1e53987f858500ec00@syzkaller.appspotmail.com
Fix commit: a91714312eb1 percpu_ref_init(): clean ->percpu_count_ref on failure
Patched on: [ci-qemu-upstream ci-qemu-upstream-386 ci-qemu2-arm32 ci-qemu2-arm64 ci-qemu2-arm64-compat ci-qemu2-arm64-mte ci-upstream-bpf-kasan-gce ci-upstream-bpf-next-kasan-gce ci-upstream-gce-leak ci-upstream-kasan-gce ci-upstream-kasan-gce-386 ci-upstream-kasan-gce-root ci-upstream-kasan-gce-selinux-root ci-upstream-kasan-gce-smack-root ci-upstream-linux-next-kasan-gce-root ci-upstream-net-kasan-gce ci-upstream-net-this-kasan-gce ci2-upstream-kcsan-gce], missing on: [ci-qemu2-riscv64 ci-upstream-kmsan-gce ci-upstream-kmsan-gce-386 ci2-upstream-usb]
First crash: 196d, last: 16d

Cause bisection: the issue happens on the oldest tested release (bisect log)
Crash: WARNING in mntput_no_expire (log)
Repro: C syz .config
similar bugs (2):
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in mntput_no_expire (2) C done 68 206d 421d 22/22 fixed on 2021/11/10 00:50
upstream WARNING in mntput_no_expire 1 497d 493d 0/22 auto-closed as invalid on 2021/03/16 10:44
Patch testing requests:
Created Duration User Patch Repo Result
2022/05/18 10:41 17m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 OK
2022/05/18 06:25 17m viro@zeniv.linux.org.uk git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git proposed-fix OK
2022/05/17 22:38 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/17 11:13 12m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/16 23:39 11m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/16 12:22 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/15 13:31 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/15 09:47 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/15 05:06 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/15 01:27 4m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 error
2022/05/14 23:35 4m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 error
2022/05/14 13:29 10m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/14 11:47 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/14 09:01 17m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/14 07:31 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/14 06:28 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/14 00:50 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/13 14:45 20m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/13 13:49 22m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/13 12:36 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/12 13:54 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/12 12:06 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log
2022/05/11 13:51 9m hdanton@sina.com patch https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/ feb9c5e19e91 report log

Sample crash report:
------------[ cut here ]------------
WARNING: CPU: 0 PID: 3608 at fs/namespace.c:1236 mntput_no_expire+0xada/0xcd0 fs/namespace.c:1236
Modules linked in:

CPU: 0 PID: 3608 Comm: syz-executor314 Not tainted 5.18.0-rc6-syzkaller-00009-gfeb9c5e19e91 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:mntput_no_expire+0xada/0xcd0 fs/namespace.c:1236
Code: 30 84 c0 0f 84 b9 fe ff ff 3c 03 0f 8f b1 fe ff ff 4c 89 44 24 10 e8 45 50 e9 ff 4c 8b 44 24 10 e9 9d fe ff ff e8 56 bf 9d ff <0f> 0b e9 19 fd ff ff e8 4a bf 9d ff e8 b5 cf 91 07 31 ff 89 c5 89
RSP: 0018:ffffc900030ffcf0 EFLAGS: 00010293

RAX: 0000000000000000 RBX: 1ffff9200061ffa4 RCX: 0000000000000000
RDX: ffff88807c859d80 RSI: ffffffff81db815a RDI: 0000000000000003
RBP: ffff88801bcbca80 R08: 0000000000000000 R09: ffffffff9006d90f
R10: ffffffff81db7e71 R11: 0000000000000001 R12: 0000000000000008
R13: ffffc900030ffd40 R14: 00000000ffffffff R15: 0000000000000002
FS:  0000555556a0e300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000555556a17628 CR3: 0000000071c9d000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 path_umount+0x7d4/0x1260 fs/namespace.c:1806
 ksys_umount fs/namespace.c:1825 [inline]
 __do_sys_umount fs/namespace.c:1830 [inline]
 __se_sys_umount fs/namespace.c:1828 [inline]
 __x64_sys_umount+0x159/0x180 fs/namespace.c:1828
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fcc5b9cc2c7
Code: 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffcb4fdf1a8 EFLAGS: 00000202 ORIG_RAX: 00000000000000a6
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fcc5b9cc2c7
RDX: 00007ffcb4fdf269 RSI: 000000000000000a RDI: 00007ffcb4fdf260
RBP: 00007ffcb4fdf260 R08: 00000000ffffffff R09: 00007ffcb4fdf040
R10: 0000555556a0f693 R11: 0000000000000202 R12: 00007ffcb4fe02e0
R13: 0000555556a0f5f0 R14: 00007ffcb4fdf1d0 R15: 0000000000000002
 </TASK>

Crashes (28):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci-upstream-kasan-gce 2022/05/11 05:34 upstream feb9c5e19e91 8d7b3b67 .config log report syz C WARNING in mntput_no_expire
ci-upstream-kasan-gce 2021/11/26 05:53 upstream b501b85957de 63eeac02 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-kasan-gce 2022/01/20 13:01 bpf baa59504c1cd 5da9499f .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-kasan-gce 2022/01/01 06:21 bpf 819d11507f66 e1768e9c .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-kasan-gce 2021/12/28 13:03 bpf 819d11507f66 6b3c5e64 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-kasan-gce 2021/12/27 16:45 bpf 819d11507f66 5140bd58 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-kasan-gce 2021/12/26 17:29 bpf 819d11507f66 e4f103c4 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-kasan-gce 2021/12/25 08:14 bpf 819d11507f66 6caa12e4 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-kasan-gce 2021/12/23 11:30 bpf 819d11507f66 6caa12e4 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-kasan-gce 2021/12/22 12:37 bpf 819d11507f66 6caa12e4 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-kasan-gce 2021/12/10 04:52 bpf ded746bfc943 4d4ce9bc .config log report info WARNING in mntput_no_expire
ci-upstream-net-this-kasan-gce 2021/12/06 04:29 net 2be6d4d16a08 a617004c .config log report info WARNING in mntput_no_expire
ci-upstream-net-this-kasan-gce 2021/11/30 01:04 net f8e7dfd6fdab d0830353 .config log report info WARNING in mntput_no_expire
ci-upstream-net-this-kasan-gce 2021/11/28 21:37 net c5c17547b778 63eeac02 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-kasan-gce 2021/11/11 22:21 bpf fceb07950a7a 75b04091 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-next-kasan-gce 2021/12/29 23:03 bpf-next 4b443bc1785f 6cc879d4 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-next-kasan-gce 2021/12/24 22:15 bpf-next 4b443bc1785f 6caa12e4 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-next-kasan-gce 2021/12/23 21:35 bpf-next 4b443bc1785f 6caa12e4 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-next-kasan-gce 2021/12/23 14:00 bpf-next 4b443bc1785f 6caa12e4 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-next-kasan-gce 2021/12/23 10:46 bpf-next 4b443bc1785f 6caa12e4 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-next-kasan-gce 2021/12/20 06:11 bpf-next 4b443bc1785f 44068e19 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-next-kasan-gce 2021/12/18 06:53 bpf-next 4b443bc1785f 44068e19 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-next-kasan-gce 2021/12/17 13:40 bpf-next 4b443bc1785f 44068e19 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-next-kasan-gce 2021/12/17 11:02 bpf-next 4b443bc1785f 44068e19 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-next-kasan-gce 2021/12/16 09:13 bpf-next 4b443bc1785f 572bcb40 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-next-kasan-gce 2021/12/16 00:52 bpf-next 4b443bc1785f 572bcb40 .config log report info WARNING in mntput_no_expire
ci-upstream-bpf-next-kasan-gce 2021/12/13 22:30 bpf-next 4b443bc1785f 49ca1f59 .config log report info WARNING in mntput_no_expire
ci-upstream-net-kasan-gce 2021/12/04 01:44 net-next bb14bfc7eb92 a617004c .config log report info WARNING in mntput_no_expire