[syzbot] [kernfs?] INFO: task hung in do_coredump (3)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: c964ced77262 Merge tag 'for-linus' of git://git.kernel.org..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=13dbcf27980000
kernel config: https://syzkaller.appspot.com/x/.config?x=64667415a04ab9c4
dashboard link: https://syzkaller.appspot.com/bug?extid=a8cdfe2d8ad35db3a7fd
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/8e033b304e7a/disk-c964ced7.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/4f886da219e0/vmlinux-c964ced7.xz
kernel image: https://storage.googleapis.com/syzbot-assets/814a8b44477f/bzImage-c964ced7.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a8cdfe...@syzkaller.appspotmail.com

INFO: task syz.0.801:10223 blocked for more than 143 seconds.
Not tainted 6.12.0-rc3-syzkaller-00087-gc964ced77262 #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.801 state:D stack:28592 pid:10223 tgid:10220 ppid:9895 flags:0x00004004
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5322 [inline]
__schedule+0xef5/0x5750 kernel/sched/core.c:6682
__schedule_loop kernel/sched/core.c:6759 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6774
schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2591
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:264
coredump_wait fs/coredump.c:418 [inline]
do_coredump+0x82f/0x4160 fs/coredump.c:575
get_signal+0x237c/0x26d0 kernel/signal.c:2902
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f282b37dff9
RSP: 002b:00007f282c1850e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f282b536060 RCX: 00007f282b37dff9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f282b536064
RBP: 00007f282b536058 R08: 00007f282c1a7080 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f282b536064
R13: 0000000000000000 R14: 00007ffcdfcd02c0 R15: 00007ffcdfcd03a8
</TASK>

Showing all locks held in the system:
3 locks held by kworker/u8:1/12:
#0: ffff88801ac89148 ((wq_completion)events_unbound){+.+.}-{0:0}, at: process_one_work+0x1212/0x1b30 kernel/workqueue.c:3204
#1: ffffc90000117d80 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205
#2: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0x51/0xc0 net/core/link_watch.c:276
1 lock held by khungtaskd/30:
#0: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720
5 locks held by kworker/u8:5/1104:
#0: ffff88801baed948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1212/0x1b30 kernel/workqueue.c:3204
#1: ffffc90003e27d80 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205
#2: ffffffff8faae510 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xbb/0xb40 net/core/net_namespace.c:580
#3: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: default_device_exit_batch+0x8f/0x9b0 net/core/dev.c:11934
#4: ffffffff8ddc30f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock+0x282/0x3b0 kernel/rcu/tree_exp.h:297
3 locks held by kworker/u8:7/2921:
#0: ffff88814c578948 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x1212/0x1b30 kernel/workqueue.c:3204
#1: ffffc90009917d80 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x8bb/0x1b30 kernel/workqueue.c:3205
#2: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcf/0x14d0 net/ipv6/addrconf.c:4196
2 locks held by dhcpcd/4901:
#0: ffff88803129c6c8 (nlk_cb_mutex-ROUTE){+.+.}-{3:3}, at: __netlink_dump_start+0x154/0x980 net/netlink/af_netlink.c:2405
#1: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#1: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_dumpit+0x18f/0x1f0 net/core/rtnetlink.c:6534
2 locks held by getty/4989:
#0: ffff888031d4a0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
1 lock held by syz.1.644/8939:
1 lock held by syz.0.801/10221:
1 lock held by syz-executor/11581:
#0: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xea0 net/core/rtnetlink.c:6672
1 lock held by syz-executor/11673:
#0: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xea0 net/core/rtnetlink.c:6672
1 lock held by syz-executor/11679:
#0: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xea0 net/core/rtnetlink.c:6672
1 lock held by syz-executor/11682:
#0: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:79 [inline]
#0: ffffffff8fac4128 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x372/0xea0 net/core/rtnetlink.c:6672

=============================================

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc3-syzkaller-00087-gc964ced77262 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
watchdog+0xf0c/0x1240 kernel/hung_task.c:379
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 8939 Comm: syz.1.644 Not tainted 6.12.0-rc3-syzkaller-00087-gc964ced77262 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
RIP: 0010:sha256_transform_rorx+0x491/0x1120 arch/x86/crypto/sha256-avx2-asm.S:600
Code: 00 c2 45 31 e6 c4 63 7b f0 e1 02 c4 c1 7d fe c0 45 31 e6 41 89 cc 41 21 d4 45 01 ef c5 fd 70 d0 50 44 09 e6 44 01 f3 45 01 f9 <44> 01 fb 01 f3 89 de c4 43 7b f0 e9 19 c4 43 7b f0 f1 0b 03 44 3c
RSP: 0018:ffffc900115f7200 EFLAGS: 00000207
RAX: 000000003357dd5f RBX: 0000000090041468 RCX: 00000000a7e785dd
RDX: 000000009f51b31d RSI: 000000008f51b59d RDI: 0000000000000080
RBP: ffffc900115f7420 R08: 00000000cd5035ab R09: 0000000068c009dd
R10: 00000000ca0dc7c0 R11: 00000000ff34e361 R12: 000000008741811d
R13: 00000000fdd296c2 R14: 00000000d903a8d4 R15: 00000000f9297221
FS: 00007f704af0b6c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000556573553680 CR3: 0000000050cbe000 CR4: 00000000003526f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
lib_sha256_base_do_update include/crypto/sha256_base.h:63 [inline]
sha256_base_do_update include/crypto/sha256_base.h:81 [inline]
_sha256_update arch/x86/crypto/sha256_ssse3_glue.c:74 [inline]
_sha256_update+0x17e/0x220 arch/x86/crypto/sha256_ssse3_glue.c:58
ima_calc_file_hash_tfm+0x302/0x3e0 security/integrity/ima/ima_crypto.c:491
ima_calc_file_shash security/integrity/ima/ima_crypto.c:511 [inline]
ima_calc_file_hash+0x1ba/0x490 security/integrity/ima/ima_crypto.c:568
ima_collect_measurement+0x8a7/0xa10 security/integrity/ima/ima_api.c:293
process_measurement+0x1271/0x2370 security/integrity/ima/ima_main.c:372
ima_file_mmap+0x1b1/0x1d0 security/integrity/ima/ima_main.c:462
security_mmap_file+0x8bd/0x990 security/security.c:2979
vm_mmap_pgoff+0xdb/0x360 mm/util.c:584
ksys_mmap_pgoff+0x1c8/0x5c0 mm/mmap.c:542
__do_sys_mmap arch/x86/kernel/sys_x86_64.c:86 [inline]
__se_sys_mmap arch/x86/kernel/sys_x86_64.c:79 [inline]
__x64_sys_mmap+0x125/0x190 arch/x86/kernel/sys_x86_64.c:79
do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f704a17dff9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f704af0b038 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007f704a335f80 RCX: 00007f704a17dff9
RDX: 00004000000000df RSI: 0000002000000004 RDI: 0000000000000002
RBP: 00007f704a1f0296 R08: 0000000000000404 R09: 0000300000000000
R10: 0000000000040eb2 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000000 R14: 00007f704a335f80 R15: 00007ffeb08cd318
</TASK>


---
This report is generated by a bot. It may contain errors.
See https://goo.gl/tpsmEJ for more information about syzbot.
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If the report is already addressed, let syzbot know by replying with:
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If the report is a duplicate of another one, reply with:
#syz dup: exact-subject-of-another-report

If you want to undo deduplication, reply with:
#syz undup

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 715ca9dd687f Merge tag 'io_uring-6.12-20241019' of git://g..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1483825f980000
kernel config: https://syzkaller.appspot.com/x/.config?x=cd54001fa72fa33d

dashboard link: https://syzkaller.appspot.com/bug?extid=a8cdfe2d8ad35db3a7fd
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11aa7240580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/a3e72f8f3c4f/disk-715ca9dd.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/7b3548f5ba14/vmlinux-715ca9dd.xz
kernel image: https://storage.googleapis.com/syzbot-assets/0d058d51ce5b/bzImage-715ca9dd.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a8cdfe...@syzkaller.appspotmail.com

INFO: task syz.3.130:5664 blocked for more than 144 seconds.
Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

task:syz.3.130 state:D stack:28592 pid:5664 tgid:5660 ppid:5353 flags:0x00004004

Call Trace:
<TASK>
context_switch kernel/sched/core.c:5322 [inline]
__schedule+0xef5/0x5750 kernel/sched/core.c:6682
__schedule_loop kernel/sched/core.c:6759 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6774
schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2591
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:264
coredump_wait fs/coredump.c:418 [inline]
do_coredump+0x82f/0x4160 fs/coredump.c:575
get_signal+0x237c/0x26d0 kernel/signal.c:2902
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f

RIP: 0033:0x7f2af557dff9
RSP: 002b:00007f2af63aa0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007f2af5736060 RCX: 00007f2af557dff9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007f2af5736064
RBP: 00007f2af5736058 R08: 00007f2af63cc080 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f2af5736064
R13: 0000000000000000 R14: 00007ffda02286a0 R15: 00007ffda0228788
</TASK>
INFO: task syz.2.131:5669 blocked for more than 144 seconds.
Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

task:syz.2.131 state:D stack:28592 pid:5669 tgid:5668 ppid:5349 flags:0x00000004

Call Trace:
<TASK>
context_switch kernel/sched/core.c:5322 [inline]
__schedule+0xef5/0x5750 kernel/sched/core.c:6682
__schedule_loop kernel/sched/core.c:6759 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6774
schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2591
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:264
coredump_wait fs/coredump.c:418 [inline]
do_coredump+0x82f/0x4160 fs/coredump.c:575
get_signal+0x237c/0x26d0 kernel/signal.c:2902
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f

RIP: 0033:0x7fa3c517dff9
RSP: 002b:00007fa3c5fb30e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007fa3c5335f88 RCX: 00007fa3c517dff9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fa3c5335f8c
RBP: 00007fa3c5335f80 R08: 00007fa3c5fb4080 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fa3c5335f8c
R13: 0000000000000000 R14: 00007fffdf878150 R15: 00007fffdf878238
</TASK>
INFO: task syz.1.159:5736 blocked for more than 145 seconds.
Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

task:syz.1.159 state:D stack:28592 pid:5736 tgid:5734 ppid:5342 flags:0x00000004

Call Trace:
<TASK>
context_switch kernel/sched/core.c:5322 [inline]
__schedule+0xef5/0x5750 kernel/sched/core.c:6682
__schedule_loop kernel/sched/core.c:6759 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6774
schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2591
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:264
coredump_wait fs/coredump.c:418 [inline]
do_coredump+0x82f/0x4160 fs/coredump.c:575
get_signal+0x237c/0x26d0 kernel/signal.c:2902
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f

RIP: 0033:0x7fac9cf7dff9
RSP: 002b:00007fac9dd3b0e8 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007fac9d136060 RCX: 00007fac9cf7dff9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fac9d136064
RBP: 00007fac9d136058 R08: 00007fac9dd5d080 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fac9d136064
R13: 0000000000000000 R14: 00007fff5f308c60 R15: 00007fff5f308d48

</TASK>

Showing all locks held in the system:

1 lock held by khungtaskd/30:

#0: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8ddb7840 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720
2 locks held by getty/4985:
#0: ffff88814c5240a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
1 lock held by syz.3.130/5667:
1 lock held by syz.2.131/5673:
1 lock held by syz.1.159/5737:
3 locks held by kworker/u8:9/5768:
3 locks held by dhcpcd/5920:
1 lock held by syz.3.181/6065:
5 locks held by syz.1.189/6169:
2 locks held by syz.2.190/6173:
2 locks held by syz.0.191/6175:
2 locks held by dhcpcd-run-hook/6176:

=============================================

NMI backtrace for cpu 0

CPU: 0 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
watchdog+0xf0c/0x1240 kernel/hung_task.c:379
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>

Sending NMI from CPU 0 to CPUs 1:

NMI backtrace for cpu 1

CPU: 1 UID: 0 PID: 5860 Comm: syz-executor Not tainted 6.12.0-rc3-syzkaller-00420-g715ca9dd687f #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024

RIP: 0010:stack_access_ok+0xc/0x200 arch/x86/kernel/unwind_orc.c:389
Code: ff e9 b0 fe ff ff 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 48 b8 00 00 00 00 00 fc ff df 41 57 <41> 56 4c 8d 77 08 41 55 41 54 49 89 d4 4c 89 f2 55 48 c1 ea 03 48
RSP: 0018:ffffc90002d8f328 EFLAGS: 00000246
RAX: dffffc0000000000 RBX: 0000000000000001 RCX: ffffffff90b840e0
RDX: 0000000000000008 RSI: ffffc90002d8fb68 RDI: ffffc90002d8f3a8
RBP: ffffc90002d8f3f0 R08: ffffffff90b840e6 R09: ffffffff90b840e4
R10: ffffc90002d8f3a8 R11: 000000000000ccb0 R12: ffffc90002d8f3f8
R13: ffffc90002d8f3a8 R14: ffffc90002d8fb70 R15: ffffc90002d8fb68
FS: 00005555721e0500(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00007f5f0ee9c000 CR3: 0000000028c4e000 CR4: 00000000003526f0

DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>

deref_stack_reg arch/x86/kernel/unwind_orc.c:403 [inline]
unwind_next_frame+0xac7/0x20c0 arch/x86/kernel/unwind_orc.c:585
arch_stack_walk+0x95/0x100 arch/x86/kernel/stacktrace.c:25
stack_trace_save+0x95/0xd0 kernel/stacktrace.c:122
save_stack+0x162/0x1f0 mm/page_owner.c:156
__reset_page_owner+0x8d/0x400 mm/page_owner.c:297
reset_page_owner include/linux/page_owner.h:25 [inline]
free_pages_prepare mm/page_alloc.c:1108 [inline]
free_unref_folios+0x956/0x1310 mm/page_alloc.c:2686
folios_put_refs+0x551/0x750 mm/swap.c:1007
folio_batch_release include/linux/pagevec.h:101 [inline]
shmem_undo_range+0x586/0x1170 mm/shmem.c:1032
shmem_truncate_range mm/shmem.c:1144 [inline]
shmem_evict_inode+0x3a3/0xba0 mm/shmem.c:1272
evict+0x409/0x970 fs/inode.c:725
iput_final fs/inode.c:1877 [inline]
iput fs/inode.c:1903 [inline]
iput+0x530/0x890 fs/inode.c:1889
do_unlinkat+0x5c3/0x760 fs/namei.c:4540
__do_sys_unlink fs/namei.c:4581 [inline]
__se_sys_unlink fs/namei.c:4579 [inline]
__x64_sys_unlink+0xc5/0x110 fs/namei.c:4579

do_syscall_x64 arch/x86/entry/common.c:52 [inline]
do_syscall_64+0xcd/0x250 arch/x86/entry/common.c:83
entry_SYSCALL_64_after_hwframe+0x77/0x7f

RIP: 0033:0x7f341997d5a7
Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 57 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fff8c61fa08 EFLAGS: 00000206 ORIG_RAX: 0000000000000057
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f341997d5a7
RDX: 00007fff8c61fa30 RSI: 00007fff8c61fac0 RDI: 00007fff8c61fac0
RBP: 00007fff8c61fac0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000206 R12: 00007fff8c620b40
R13: 00007f34199f0134 R14: 0000000000064daa R15: 00007fff8c620b80
</TASK>


---
If you want syzbot to run the reproducer, reply with:
#syz test: git://repo/address.git branch-or-commit-hash
If you attach or paste a git patch, syzbot will apply it before testing.

[syzbot]

syzbot has found a reproducer for the following issue on:

HEAD commit: 819837584309 Linux 6.12-rc5
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=16356ca7980000
kernel config: https://syzkaller.appspot.com/x/.config?x=1940f73a609bb874

dashboard link: https://syzkaller.appspot.com/bug?extid=a8cdfe2d8ad35db3a7fd
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

syz repro: https://syzkaller.appspot.com/x/repro.syz?x=171b4687980000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=10bd3230580000

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/5d6f005bb493/disk-81983758.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/9e1428c416c8/vmlinux-81983758.xz
kernel image: https://storage.googleapis.com/syzbot-assets/970a44403f00/bzImage-81983758.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+a8cdfe...@syzkaller.appspotmail.com

INFO: task syz-executor377:5856 blocked for more than 143 seconds.
Not tainted 6.12.0-rc5-syzkaller #0

"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.

task:syz-executor377 state:D stack:28560 pid:5856 tgid:5854 ppid:5853 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5328 [inline]
__schedule+0xe55/0x5730 kernel/sched/core.c:6690
__schedule_loop kernel/sched/core.c:6767 [inline]
schedule+0xe7/0x350 kernel/sched/core.c:6782

schedule_timeout+0x258/0x2a0 kernel/time/timer.c:2591
do_wait_for_common kernel/sched/completion.c:95 [inline]
__wait_for_common+0x3e1/0x600 kernel/sched/completion.c:116
wait_for_common kernel/sched/completion.c:127 [inline]
wait_for_completion_state+0x1c/0x40 kernel/sched/completion.c:264
coredump_wait fs/coredump.c:418 [inline]
do_coredump+0x82f/0x4160 fs/coredump.c:575
get_signal+0x237c/0x26d0 kernel/signal.c:2902
arch_do_signal_or_restart+0x90/0x7e0 arch/x86/kernel/signal.c:337
exit_to_user_mode_loop kernel/entry/common.c:111 [inline]
exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline]
__syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline]
syscall_exit_to_user_mode+0x150/0x2a0 kernel/entry/common.c:218
do_syscall_64+0xda/0x250 arch/x86/entry/common.c:89
entry_SYSCALL_64_after_hwframe+0x77/0x7f

RIP: 0033:0x7fc0089ce2e9
RSP: 002b:00007fc008968218 EFLAGS: 00000246 ORIG_RAX: 00000000000000ca
RAX: ffffffffffffffda RBX: 00007fc008a58318 RCX: 00007fc0089ce2e9
RDX: 00000000000f4240 RSI: 0000000000000081 RDI: 00007fc008a5831c
RBP: 00007fc008a58310 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000005 R11: 0000000000000246 R12: 00007fc008a5831c
R13: 0008000000000001 R14: 00004000000000df R15: 0000300000000000

</TASK>

Showing all locks held in the system:

1 lock held by khungtaskd/30:
#0: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:337 [inline]
#0: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:849 [inline]
#0: ffffffff8ddb7800 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x7f/0x390 kernel/locking/lockdep.c:6720

2 locks held by syslogd/5195:
#0: ffff8880b863ee98 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x29/0x130 kernel/sched/core.c:598
#1: ffffffff9a5faf30 (&obj_hash[i].lock){-.-.}-{2:2}, at: __skb_try_recv_datagram+0x149/0x4f0 net/core/datagram.c:263
2 locks held by getty/5606:
#0: ffff8880350da0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
#1: ffffc90002f062f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xfba/0x1480 drivers/tty/n_tty.c:2211
1 lock held by syz-executor377/5855:

=============================================

NMI backtrace for cpu 1

CPU: 1 UID: 0 PID: 30 Comm: khungtaskd Not tainted 6.12.0-rc5-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:94 [inline]
dump_stack_lvl+0x116/0x1f0 lib/dump_stack.c:120
nmi_cpu_backtrace+0x27b/0x390 lib/nmi_backtrace.c:113
nmi_trigger_cpumask_backtrace+0x29c/0x300 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:162 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:223 [inline]
watchdog+0xf0c/0x1240 kernel/hung_task.c:379
kthread+0x2c1/0x3a0 kernel/kthread.c:389
ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
</TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0

CPU: 0 UID: 0 PID: 5855 Comm: syz-executor377 Not tainted 6.12.0-rc5-syzkaller #0

Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024

RIP: 0010:sha256_transform_rorx+0xfd9/0x1120 arch/x86/crypto/sha256-avx2-asm.S:655
Code: 38 09 d6 45 31 e6 41 89 cc 44 21 c6 41 21 d4 45 01 ef 41 01 d9 44 09 e6 44 01 f3 45 01 f9 44 01 fb 45 89 d7 c4 43 7b f0 e9 19 <c4> 43 7b f0 f1 0b 45 31 df 45 31 f5 c4 43 7b f0 f1 06 45 21 cf 01
RSP: 0018:ffffc9000381f200 EFLAGS: 00000297
RAX: 0000000082170eda RBX: 00000000aaf713b2 RCX: 00000000dd0d3fb4
RDX: 0000000083a209e1 RSI: 00000000dd051db4 RDI: 00000000000001c0
RBP: ffffc9000381f420 R08: 000000007d459d16 R09: 000000002d345c33
R10: 00000000bb0c1e52 R11: 00000000ff949dec R12: 00000000810009a0
R13: 000000009a2e1996 R14: 00000000fe1b74f0 R15: 00000000bb0c1e52
FS: 00007fc0089896c0(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000

CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033

CR2: 00005614eea51680 CR3: 0000000079270000 CR4: 00000000003526f0

RIP: 0033:0x7fc0089ce2e9
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc008989208 EFLAGS: 00000246 ORIG_RAX: 0000000000000009
RAX: ffffffffffffffda RBX: 00007fc008a58308 RCX: 00007fc0089ce2e9
RDX: 00004000000000df RSI: 0008000000000001 RDI: 0000000000000000
RBP: 00007fc008a58300 R08: 0000000000000401 R09: 0000300000000000
R10: 0000000000040eb1 R11: 0000000000000246 R12: 00007fc008a5830c
R13: 0008000000000001 R14: 00004000000000df R15: 0000300000000000
</TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.168 msecs

[Hillf Danton]

On Mon, 28 Oct 2024 15:23:20 -0700

> syzbot has found a reproducer for the following issue on:
>
> HEAD commit: 819837584309 Linux 6.12-rc5
> git tree: upstream

> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=171b4687980000

#syz test

--- x/fs/coredump.c
+++ y/fs/coredump.c
@@ -416,7 +416,7 @@ static int coredump_wait(int exit_code,
struct core_thread *ptr;

wait_for_completion_state(&core_state->startup,
- TASK_UNINTERRUPTIBLE|TASK_FREEZABLE);
+ TASK_IDLE|TASK_FREEZABLE);
/*
* Wait for all the threads to become inactive, so that
* all the thread context (extended register state, like
--

[syzbot]

Hello,

syzbot tried to test the proposed patch but the build/boot failed:

failed to copy binary to VM: failed to run ["scp" "-P" "22" "-F" "/dev/null" "-o" "UserKnownHostsFile=/dev/null" "-o" "IdentitiesOnly=yes" "-o" "BatchMode=yes" "-o" "StrictHostKeyChecking=no" "-o" "ConnectTimeout=10" "-v" "/tmp/syz-executor448792031" "ro...@10.128.1.66:./syz-executor448792031"]: exit status 255
Executing: program /usr/bin/ssh host 10.128.1.66, user root, command sftp
OpenSSH_9.2p1 Debian-2+deb12u3, OpenSSL 3.0.14 4 Jun 2024
debug1: Reading configuration data /dev/null
debug1: Connecting to 10.128.1.66 [10.128.1.66] port 22.
debug1: fd 3 clearing O_NONBLOCK
debug1: Connection established.
debug1: identity file /root/.ssh/id_rsa type -1
debug1: identity file /root/.ssh/id_rsa-cert type -1
debug1: identity file /root/.ssh/id_ecdsa type -1
debug1: identity file /root/.ssh/id_ecdsa-cert type -1
debug1: identity file /root/.ssh/id_ecdsa_sk type -1
debug1: identity file /root/.ssh/id_ecdsa_sk-cert type -1
debug1: identity file /root/.ssh/id_ed25519 type -1
debug1: identity file /root/.ssh/id_ed25519-cert type -1
debug1: identity file /root/.ssh/id_ed25519_sk type -1
debug1: identity file /root/.ssh/id_ed25519_sk-cert type -1
debug1: identity file /root/.ssh/id_xmss type -1
debug1: identity file /root/.ssh/id_xmss-cert type -1
debug1: identity file /root/.ssh/id_dsa type -1
debug1: identity file /root/.ssh/id_dsa-cert type -1
debug1: Local version string SSH-2.0-OpenSSH_9.2p1 Debian-2+deb12u3
Connection timed out during banner exchange
Connection to 10.128.1.66 port 22 timed out
scp: Connection closed




syzkaller build log:
go env (err=<nil>)
GO111MODULE='auto'
GOARCH='amd64'
GOBIN=''
GOCACHE='/syzkaller/.cache/go-build'
GOENV='/syzkaller/.config/go/env'
GOEXE=''
GOEXPERIMENT=''
GOFLAGS=''
GOHOSTARCH='amd64'
GOHOSTOS='linux'
GOINSECURE=''
GOMODCACHE='/syzkaller/jobs/linux/gopath/pkg/mod'
GONOPROXY=''
GONOSUMDB=''
GOOS='linux'
GOPATH='/syzkaller/jobs/linux/gopath'
GOPRIVATE=''
GOPROXY='https://proxy.golang.org,direct'
GOROOT='/usr/local/go'
GOSUMDB='sum.golang.org'
GOTMPDIR=''
GOTOOLCHAIN='auto'
GOTOOLDIR='/usr/local/go/pkg/tool/linux_amd64'
GOVCS=''
GOVERSION='go1.22.7'
GCCGO='gccgo'
GOAMD64='v1'
AR='ar'
CC='gcc'
CXX='g++'
CGO_ENABLED='1'
GOMOD='/syzkaller/jobs/linux/gopath/src/github.com/google/syzkaller/go.mod'
GOWORK=''
CGO_CFLAGS='-O2 -g'
CGO_CPPFLAGS=''
CGO_CXXFLAGS='-O2 -g'
CGO_FFLAGS='-O2 -g'
CGO_LDFLAGS='-O2 -g'
PKG_CONFIG='pkg-config'
GOGCCFLAGS='-fPIC -m64 -pthread -Wl,--no-gc-sections -fmessage-length=0 -ffile-prefix-map=/tmp/go-build236127509=/tmp/go-build -gno-record-gcc-switches'

git status (err=<nil>)
HEAD detached at 5fe1d0f516
nothing to commit, working tree clean


tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
go list -f '{{.Stale}}' ./sys/syz-sysgen | grep -q false || go install ./sys/syz-sysgen
make .descriptions
tput: No value for $TERM and no -T specified
tput: No value for $TERM and no -T specified
Makefile:31: run command via tools/syz-env for best compatibility, see:
Makefile:32: https://github.com/google/syzkaller/blob/master/docs/contributing.md#using-syz-env
bin/syz-sysgen
go fmt ./sys/... >/dev/null
touch .descriptions
GOOS=linux GOARCH=amd64 go build "-ldflags=-s -w -X github.com/google/syzkaller/prog.GitRevision=5fe1d0f516ac169c2b6e3a268aea92df864ea3a6 -X 'github.com/google/syzkaller/prog.gitRevisionDate=20241028-155739'" "-tags=syz_target syz_os_linux syz_arch_amd64 " -o ./bin/linux_amd64/syz-execprog github.com/google/syzkaller/tools/syz-execprog
mkdir -p ./bin/linux_amd64
g++ -o ./bin/linux_amd64/syz-executor executor/executor.cc \
-m64 -O2 -pthread -Wall -Werror -Wparentheses -Wunused-const-variable -Wframe-larger-than=16384 -Wno-stringop-overflow -Wno-array-bounds -Wno-format-overflow -Wno-unused-but-set-variable -Wno-unused-command-line-argument -static-pie -std=c++17 -I. -Iexecutor/_include -fpermissive -w -DGOOS_linux=1 -DGOARCH_amd64=1 \
-DHOSTGOOS_linux=1 -DGIT_REVISION=\"5fe1d0f516ac169c2b6e3a268aea92df864ea3a6\"
/usr/bin/ld: /tmp/ccsbdreI.o: in function `test_cover_filter()':
executor.cc:(.text+0x1426b): warning: the use of `tempnam' is dangerous, better use `mkstemp'
/usr/bin/ld: /tmp/ccsbdreI.o: in function `Connection::Connect(char const*, char const*)':
executor.cc:(.text._ZN10Connection7ConnectEPKcS1_[_ZN10Connection7ConnectEPKcS1_]+0x104): warning: Using 'gethostbyname' in statically linked applications requires at runtime the shared libraries from the glibc version used for linking



Tested on:

commit: e42b1a9a Merge tag 'spi-fix-v6.12-rc5' of git://git.ke..
git tree: upstream

kernel config: https://syzkaller.appspot.com/x/.config?x=1940f73a609bb874
dashboard link: https://syzkaller.appspot.com/bug?extid=a8cdfe2d8ad35db3a7fd
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=1729eca7980000

[Hillf Danton]

On Mon, 28 Oct 2024 15:23:20 -0700

> syzbot has found a reproducer for the following issue on:
>
> HEAD commit: 819837584309 Linux 6.12-rc5
> git tree: upstream

> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=171b4687980000

#syz test upstream master

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
INFO: rcu detected stall in corrupted

rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { P1029 } 3639 jiffies s: 9185 root: 0x0/T
rcu: blocking rcu_node structures (internal RCU debug):


Tested on:

commit: c1e939a2 Merge tag 'cgroup-for-6.12-rc5-fixes' of git:..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1408e540580000

kernel config: https://syzkaller.appspot.com/x/.config?x=1940f73a609bb874
dashboard link: https://syzkaller.appspot.com/bug?extid=a8cdfe2d8ad35db3a7fd
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=1620e540580000

[Hillf Danton]

On Mon, 28 Oct 2024 15:23:20 -0700

> syzbot has found a reproducer for the following issue on:
>
> HEAD commit: 819837584309 Linux 6.12-rc5
> git tree: upstream

> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=171b4687980000

#syz test: git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git/ mm-hotfixes-unstable

[syzbot]

Hello,

syzbot has tested the proposed patch but the reproducer is still triggering an issue:
INFO: rcu detected stall in corrupted

rcu: INFO: rcu_preempt detected expedited stalls on CPUs/tasks: { P3585 } 2769 jiffies s: 8817 root: 0x0/T

rcu: blocking rcu_node structures (internal RCU debug):


Tested on:

commit: 270c32fa MAINTAINERS: remove Florian from DSA entry
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git/ mm-hotfixes-unstable
console output: https://syzkaller.appspot.com/x/log.txt?x=12afe6f7980000

kernel config: https://syzkaller.appspot.com/x/.config?x=1940f73a609bb874
dashboard link: https://syzkaller.appspot.com/bug?extid=a8cdfe2d8ad35db3a7fd
compiler: gcc (Debian 12.2.0-14) 12.2.0, GNU ld (GNU Binutils for Debian) 2.40

patch: https://syzkaller.appspot.com/x/patch.diff?x=15c9b2a7980000

[syzbot]

syzbot has bisected this issue to:

commit 2af89abda7d9c2aeb573677e2c498ddb09f8058a
Author: Pavel Begunkov <asml.s...@gmail.com>
Date: Thu Aug 24 22:53:32 2023 +0000

io_uring: add option to remove SQ indirection

bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14ec9582580000
start commit: 05df91921da6 Merge tag 'v6.16-rc4-smb3-client-fixes' of gi..
git tree: upstream
final oops: https://syzkaller.appspot.com/x/report.txt?x=16ec9582580000
console output: https://syzkaller.appspot.com/x/log.txt?x=12ec9582580000
kernel config: https://syzkaller.appspot.com/x/.config?x=45bd916a213c79bb
dashboard link: https://syzkaller.appspot.com/bug?extid=a8cdfe2d8ad35db3a7fd
syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11a2228c580000
C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16d48bd4580000

Reported-by: syzbot+a8cdfe...@syzkaller.appspotmail.com
Fixes: 2af89abda7d9 ("io_uring: add option to remove SQ indirection")

For information about bisection process see: https://goo.gl/tpsmEJ#bisection

[Pavel Begunkov]

On 7/7/25 17:27, syzbot wrote:
> syzbot has bisected this issue to:
>
> commit 2af89abda7d9c2aeb573677e2c498ddb09f8058a
> Author: Pavel Begunkov <asml.s...@gmail.com>
> Date: Thu Aug 24 22:53:32 2023 +0000
>
> io_uring: add option to remove SQ indirection

Doesn't look like the cause, the previous repro from 28 Oct 2024 didn't
even have any io_uring, and the patch only reduces sizes of some
allocations. The common part b/w programs is
prctl(PR_SET_SYSCALL_USER_DISPATCH_ON), might be related to that.

> bisection log: https://syzkaller.appspot.com/x/bisect.txt?x=14ec9582580000
> start commit: 05df91921da6 Merge tag 'v6.16-rc4-smb3-client-fixes' of gi..
> git tree: upstream
> final oops: https://syzkaller.appspot.com/x/report.txt?x=16ec9582580000
> console output: https://syzkaller.appspot.com/x/log.txt?x=12ec9582580000
> kernel config: https://syzkaller.appspot.com/x/.config?x=45bd916a213c79bb
> dashboard link: https://syzkaller.appspot.com/bug?extid=a8cdfe2d8ad35db3a7fd
> syz repro: https://syzkaller.appspot.com/x/repro.syz?x=11a2228c580000
> C reproducer: https://syzkaller.appspot.com/x/repro.c?x=16d48bd4580000
>
> Reported-by: syzbot+a8cdfe...@syzkaller.appspotmail.com
> Fixes: 2af89abda7d9 ("io_uring: add option to remove SQ indirection")
>
> For information about bisection process see: https://goo.gl/tpsmEJ#bisection

--
Pavel Begunkov