* Re: [syzbot] [jfs?] KASAN: use-after-free Read in jfs_lazycommit
[not found] <177759080895.1633114.18321249853733805964@gmail.com>
@ 2026-05-04 21:58 ` syzbot
0 siblings, 0 replies; 4+ messages in thread
From: syzbot @ 2026-05-04 21:58 UTC (permalink / raw)
To: linux-kernel, syzkaller-bugs, tristmd
Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Read in lbmIODone
==================================================================
BUG: KASAN: slab-use-after-free in lbmIODone+0x1312/0x16c0 fs/jfs/jfs_logmgr.c:2192
Read of size 4 at addr ffff8880288d8808 by task ksoftirqd/1/30
CPU: 1 UID: 0 PID: 30 Comm: ksoftirqd/1 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description+0x55/0x1e0 mm/kasan/report.c:378
print_report+0x58/0x70 mm/kasan/report.c:482
kasan_report+0x117/0x150 mm/kasan/report.c:595
lbmIODone+0x1312/0x16c0 fs/jfs/jfs_logmgr.c:2192
blk_update_request+0x57e/0xe60 block/blk-mq.c:1016
blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1178
blk_complete_reqs block/blk-mq.c:1253 [inline]
blk_done_softirq+0x10a/0x160 block/blk-mq.c:1258
handle_softirqs+0x1de/0x6d0 kernel/softirq.c:622
run_ksoftirqd+0x52/0x180 kernel/softirq.c:1076
smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Allocated by task 6825:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x3a6/0x690 mm/slub.c:5419
kmalloc_noprof include/linux/slab.h:950 [inline]
lbmLogInit fs/jfs/jfs_logmgr.c:1819 [inline]
lmLogInit+0x3e5/0x1a00 fs/jfs/jfs_logmgr.c:1267
open_inline_log fs/jfs/jfs_logmgr.c:1173 [inline]
lmLogOpen+0x4e1/0xfa0 fs/jfs/jfs_logmgr.c:1067
jfs_mount_rw+0xee/0x670 fs/jfs/jfs_mount.c:257
jfs_fill_super+0x754/0xd80 fs/jfs/super.c:532
get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
vfs_get_tree+0x92/0x2a0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3758 [inline]
do_new_mount+0x341/0xd30 fs/namespace.c:3834
do_mount fs/namespace.c:4167 [inline]
__do_sys_mount fs/namespace.c:4383 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4360
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 6185:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2689 [inline]
slab_free mm/slub.c:6250 [inline]
kfree+0x1c5/0x6c0 mm/slub.c:6565
lbmLogShutdown fs/jfs/jfs_logmgr.c:1862 [inline]
lmLogShutdown+0x456/0x850 fs/jfs/jfs_logmgr.c:1681
lmLogClose+0x28a/0x520 fs/jfs/jfs_logmgr.c:1457
jfs_umount+0x304/0x3e0 fs/jfs/jfs_umount.c:131
jfs_put_super+0x8c/0x190 fs/jfs/super.c:194
generic_shutdown_super+0x13d/0x2d0 fs/super.c:646
kill_block_super+0x44/0x90 fs/super.c:1725
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff8880288d8800
which belongs to the cache kmalloc-256 of size 256
The buggy address is located 8 bytes inside of
freed 256-byte region [ffff8880288d8800, ffff8880288d8900)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x288d8
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88801a00bb40 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 0080000000000040 ffff88801a00bb40 dead000000000100 dead000000000122
head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 0080000000000001 ffffffffffffff81 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6195, tgid 6195 (syz-executor), ts 161241515110, free_ts 160975328446
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x231/0x280 mm/page_alloc.c:1858
prep_new_page mm/page_alloc.c:1866 [inline]
get_page_from_freelist+0x27c8/0x2840 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5226
alloc_slab_page mm/slub.c:3278 [inline]
allocate_slab+0x77/0x660 mm/slub.c:3467
new_slab mm/slub.c:3525 [inline]
refill_objects+0x33c/0x3d0 mm/slub.c:7255
refill_sheaf mm/slub.c:2816 [inline]
__pcs_replace_empty_main+0x373/0x720 mm/slub.c:4651
alloc_from_pcs mm/slub.c:4749 [inline]
slab_alloc_node mm/slub.c:4883 [inline]
__do_kmalloc_node mm/slub.c:5294 [inline]
__kmalloc_noprof+0x530/0x7b0 mm/slub.c:5307
kmalloc_noprof include/linux/slab.h:954 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
fib_create_info+0x1723/0x31f0 net/ipv4/fib_semantics.c:1400
fib_table_insert+0xc8/0x1b50 net/ipv4/fib_trie.c:1212
fib_magic+0x434/0x510 net/ipv4/fib_frontend.c:1134
fib_add_ifaddr+0x144/0x5f0 net/ipv4/fib_frontend.c:1156
fib_netdev_event+0x382/0x490 net/ipv4/fib_frontend.c:1516
notifier_call_chain+0x1ad/0x3d0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2287 [inline]
call_netdevice_notifiers net/core/dev.c:2301 [inline]
__dev_notify_flags+0x1a9/0x310 net/core/dev.c:9794
netif_change_flags+0xe8/0x1a0 net/core/dev.c:9823
do_setlink+0xfa5/0x45a0 net/core/rtnetlink.c:3180
page last free pid 6195 tgid 6195 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1402 [inline]
__free_frozen_pages+0xfa6/0x10f0 mm/page_alloc.c:2943
__slab_free+0x252/0x2a0 mm/slub.c:5612
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4569 [inline]
slab_alloc_node mm/slub.c:4898 [inline]
kmem_cache_alloc_lru_noprof+0x33c/0x680 mm/slub.c:4917
sock_alloc_inode+0x2c/0x190 net/socket.c:328
alloc_inode+0x6a/0x1b0 fs/inode.c:345
new_inode_pseudo include/linux/fs.h:3015 [inline]
sock_alloc net/socket.c:697 [inline]
__sock_create+0x12d/0x9d0 net/socket.c:1628
sock_create net/socket.c:1722 [inline]
__sys_socket_create net/socket.c:1759 [inline]
__sys_socket+0xd6/0x1b0 net/socket.c:1806
__do_sys_socket net/socket.c:1820 [inline]
__se_sys_socket net/socket.c:1818 [inline]
__x64_sys_socket+0x7a/0x90 net/socket.c:1818
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff8880288d8700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff8880288d8780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff8880288d8800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff8880288d8880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff8880288d8900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
Tested on:
commit: c7e4e4d5 Merge tag 'for-linus-7.1-2' of https://github..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=11033f6c580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f2e8ebfec4636d32
dashboard link: https://syzkaller.appspot.com/bug?extid=885a4f3281b8d99c48d8
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
patch: https://syzkaller.appspot.com/x/patch.diff?x=1778bece580000
^ permalink raw reply [flat|nested] 4+ messages in thread
[parent not found: <69f9e3be.050a0220.c7d39.a142@mx.google.com>]
* Re: [syzbot] [jfs?] KASAN: use-after-free Read in jfs_lazycommit
[not found] <69f9e3be.050a0220.c7d39.a142@mx.google.com>
@ 2026-05-05 13:26 ` syzbot
0 siblings, 0 replies; 4+ messages in thread
From: syzbot @ 2026-05-05 13:26 UTC (permalink / raw)
To: linux-kernel, syzkaller-bugs, tristmd
Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Read in blk_update_request
==================================================================
BUG: KASAN: slab-use-after-free in __raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
BUG: KASAN: slab-use-after-free in _raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
Read of size 1 at addr ffff88802a964100 by task kworker/u8:7/165
CPU: 0 UID: 0 PID: 165 Comm: kworker/u8:7 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Workqueue: netns cleanup_net
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description+0x55/0x1e0 mm/kasan/report.c:378
print_report+0x58/0x70 mm/kasan/report.c:482
kasan_report+0x117/0x150 mm/kasan/report.c:595
__kasan_check_byte+0x2a/0x40 mm/kasan/common.c:574
kasan_check_byte include/linux/kasan.h:402 [inline]
lock_acquire+0x84/0x350 kernel/locking/lockdep.c:5842
__raw_spin_lock_irqsave include/linux/spinlock_api_smp.h:132 [inline]
_raw_spin_lock_irqsave+0x40/0x60 kernel/locking/spinlock.c:166
rtlock_slowlock kernel/locking/rtmutex.c:1913 [inline]
rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
__rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
rt_spin_lock+0x157/0x400 kernel/locking/spinlock_rt.c:57
spin_lock include/linux/spinlock_rt.h:45 [inline]
__wake_up_common_lock+0x2f/0x1e0 kernel/sched/wait.c:124
blk_update_request+0x57e/0xe60 block/blk-mq.c:1016
blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1178
blk_complete_reqs block/blk-mq.c:1253 [inline]
blk_done_softirq+0x10a/0x160 block/blk-mq.c:1258
handle_softirqs+0x1de/0x6d0 kernel/softirq.c:622
__do_softirq kernel/softirq.c:656 [inline]
__local_bh_enable_ip+0x170/0x2b0 kernel/softirq.c:302
local_bh_enable include/linux/bottom_half.h:33 [inline]
spin_unlock_bh include/linux/spinlock_rt.h:116 [inline]
__fib6_clean_all+0x4d1/0x610 net/ipv6/ip6_fib.c:2325
rt6_sync_down_dev net/ipv6/route.c:5018 [inline]
rt6_disable_ip+0x11f/0x750 net/ipv6/route.c:5023
addrconf_ifdown+0x157/0x1aa0 net/ipv6/addrconf.c:3865
addrconf_notify+0x1bc/0x1050 net/ipv6/addrconf.c:-1
notifier_call_chain+0x1ad/0x3d0 kernel/notifier.c:85
call_netdevice_notifiers_extack net/core/dev.c:2287 [inline]
call_netdevice_notifiers net/core/dev.c:2301 [inline]
netif_close_many+0x2ae/0x420 net/core/dev.c:1805
unregister_netdevice_many_notify+0xb50/0x22b0 net/core/dev.c:12388
unregister_netdevice_many net/core/dev.c:12481 [inline]
default_device_exit_batch+0x981/0xa00 net/core/dev.c:13073
ops_exit_list net/core/net_namespace.c:205 [inline]
ops_undo_list+0x52b/0x940 net/core/net_namespace.c:252
cleanup_net+0x56e/0x800 net/core/net_namespace.c:702
process_one_work kernel/workqueue.c:3302 [inline]
process_scheduled_works+0xb5d/0x1860 kernel/workqueue.c:3385
worker_thread+0xa53/0xfc0 kernel/workqueue.c:3466
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Allocated by task 8907:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x3a6/0x690 mm/slub.c:5419
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
open_inline_log fs/jfs/jfs_logmgr.c:1157 [inline]
lmLogOpen+0x2d1/0xfa0 fs/jfs/jfs_logmgr.c:1067
jfs_mount_rw+0xee/0x670 fs/jfs/jfs_mount.c:257
jfs_fill_super+0x754/0xd80 fs/jfs/super.c:532
get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
vfs_get_tree+0x92/0x2a0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3758 [inline]
do_new_mount+0x341/0xd30 fs/namespace.c:3834
do_mount fs/namespace.c:4167 [inline]
__do_sys_mount fs/namespace.c:4383 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4360
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 8892:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2689 [inline]
slab_free mm/slub.c:6250 [inline]
kfree+0x1c5/0x6c0 mm/slub.c:6565
lmLogClose+0x297/0x520 fs/jfs/jfs_logmgr.c:-1
jfs_umount+0x304/0x3e0 fs/jfs/jfs_umount.c:131
jfs_put_super+0x8c/0x190 fs/jfs/super.c:194
generic_shutdown_super+0x13d/0x2d0 fs/super.c:646
kill_block_super+0x44/0x90 fs/super.c:1725
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88802a964000
which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 256 bytes inside of
freed 2048-byte region [ffff88802a964000, ffff88802a964800)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88802a961000 pfn:0x2a960
head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x80000000000240(workingset|head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000240 ffff88801a010000 ffffea0000ebf410 ffffea0001007a10
raw: ffff88802a961000 0000000800080007 00000000f5000000 0000000000000000
head: 0080000000000240 ffff88801a010000 ffffea0000ebf410 ffffea0001007a10
head: ffff88802a961000 0000000800080007 00000000f5000000 0000000000000000
head: 0080000000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 1, tgid 1 (swapper/0), ts 11357773279, free_ts 0
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x231/0x280 mm/page_alloc.c:1858
prep_new_page mm/page_alloc.c:1866 [inline]
get_page_from_freelist+0x27c8/0x2840 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5226
alloc_slab_page mm/slub.c:3278 [inline]
allocate_slab+0x77/0x660 mm/slub.c:3467
new_slab mm/slub.c:3525 [inline]
refill_objects+0x33c/0x3d0 mm/slub.c:7255
refill_sheaf mm/slub.c:2816 [inline]
__pcs_replace_empty_main+0x373/0x720 mm/slub.c:4651
alloc_from_pcs mm/slub.c:4749 [inline]
slab_alloc_node mm/slub.c:4883 [inline]
__kmalloc_cache_noprof+0x44e/0x690 mm/slub.c:5414
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
hub_probe+0x571/0x3c30 drivers/usb/core/hub.c:1961
usb_probe_interface+0x659/0xc70 drivers/usb/core/driver.c:396
call_driver_probe drivers/base/dd.c:-1 [inline]
really_probe+0x267/0xaf0 drivers/base/dd.c:709
__driver_probe_device+0x1ef/0x380 drivers/base/dd.c:871
driver_probe_device+0x4f/0x240 drivers/base/dd.c:901
__device_attach_driver+0x279/0x430 drivers/base/dd.c:1029
bus_for_each_drv+0x25b/0x2f0 drivers/base/bus.c:500
__device_attach+0x2c8/0x450 drivers/base/dd.c:1101
device_initial_probe+0xa1/0xd0 drivers/base/dd.c:1156
page_owner free stack trace missing
Memory state around the buggy address:
ffff88802a964000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88802a964080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff88802a964100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88802a964180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88802a964200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
Tested on:
commit: a293ec25 Merge tag 'linux_kselftest-fixes-7.1-rc3' of ..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=146a4ad2580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f2e8ebfec4636d32
dashboard link: https://syzkaller.appspot.com/bug?extid=885a4f3281b8d99c48d8
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
patch: https://syzkaller.appspot.com/x/patch.diff?x=171e59ce580000
^ permalink raw reply [flat|nested] 4+ messages in thread
[parent not found: <177793457212.208789.6662052297059821760@gmail.com>]
* Re: [syzbot] [jfs?] KASAN: use-after-free Read in jfs_lazycommit
[not found] <177793457212.208789.6662052297059821760@gmail.com>
@ 2026-05-04 23:23 ` syzbot
0 siblings, 0 replies; 4+ messages in thread
From: syzbot @ 2026-05-04 23:23 UTC (permalink / raw)
To: linux-kernel, syzkaller-bugs, tristmd
Hello,
syzbot has tested the proposed patch but the reproducer is still triggering an issue:
KASAN: slab-use-after-free Read in lbmIODone
==================================================================
==================================================================
BUG: KASAN: slab-use-after-free in lbmIODone+0x1418/0x17a0 fs/jfs/jfs_logmgr.c:2308
Read of size 4 at addr ffff88803d442608 by task ksoftirqd/0/15
CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)}
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026
Call Trace:
<TASK>
dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120
print_address_description+0x55/0x1e0 mm/kasan/report.c:378
print_report+0x58/0x70 mm/kasan/report.c:482
kasan_report+0x117/0x150 mm/kasan/report.c:595
lbmIODone+0x1418/0x17a0 fs/jfs/jfs_logmgr.c:2308
blk_update_request+0x57e/0xe60 block/blk-mq.c:1016
blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1178
blk_complete_reqs block/blk-mq.c:1253 [inline]
blk_done_softirq+0x10a/0x160 block/blk-mq.c:1258
handle_softirqs+0x1de/0x6d0 kernel/softirq.c:622
run_ksoftirqd+0x52/0x180 kernel/softirq.c:1076
smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160
kthread+0x388/0x470 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
Allocated by task 6769:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
poison_kmalloc_redzone mm/kasan/common.c:398 [inline]
__kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415
kasan_kmalloc include/linux/kasan.h:263 [inline]
__kmalloc_cache_noprof+0x3a6/0x690 mm/slub.c:5419
kmalloc_noprof include/linux/slab.h:950 [inline]
lbmLogInit fs/jfs/jfs_logmgr.c:1820 [inline]
lmLogInit+0x3ee/0x18b0 fs/jfs/jfs_logmgr.c:1267
open_inline_log fs/jfs/jfs_logmgr.c:1173 [inline]
lmLogOpen+0x4e1/0xfa0 fs/jfs/jfs_logmgr.c:1067
jfs_mount_rw+0xee/0x670 fs/jfs/jfs_mount.c:257
jfs_fill_super+0x754/0xd80 fs/jfs/super.c:532
get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1694
vfs_get_tree+0x92/0x2a0 fs/super.c:1754
fc_mount fs/namespace.c:1193 [inline]
do_new_mount_fc fs/namespace.c:3758 [inline]
do_new_mount+0x341/0xd30 fs/namespace.c:3834
do_mount fs/namespace.c:4167 [inline]
__do_sys_mount fs/namespace.c:4383 [inline]
__se_sys_mount+0x31d/0x420 fs/namespace.c:4360
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Freed by task 6192:
kasan_save_stack mm/kasan/common.c:57 [inline]
kasan_save_track+0x3e/0x80 mm/kasan/common.c:78
kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584
poison_slab_object mm/kasan/common.c:253 [inline]
__kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:2689 [inline]
slab_free mm/slub.c:6250 [inline]
kfree+0x1c5/0x6c0 mm/slub.c:6565
lbmLogShutdown+0x283/0x350 fs/jfs/jfs_logmgr.c:1865
lmLogShutdown+0x415/0x780 fs/jfs/jfs_logmgr.c:1681
lmLogClose+0x28a/0x520 fs/jfs/jfs_logmgr.c:1457
jfs_umount+0x2fb/0x3d0 fs/jfs/jfs_umount.c:124
jfs_put_super+0x8c/0x190 fs/jfs/super.c:194
generic_shutdown_super+0x13d/0x2d0 fs/super.c:646
kill_block_super+0x44/0x90 fs/super.c:1725
deactivate_locked_super+0xbc/0x130 fs/super.c:476
cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312
task_work_run+0x1d9/0x270 kernel/task_work.c:233
resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
__exit_to_user_mode_loop kernel/entry/common.c:67 [inline]
exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98
__exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline]
syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100
entry_SYSCALL_64_after_hwframe+0x77/0x7f
The buggy address belongs to the object at ffff88803d442600
which belongs to the cache kmalloc-256 of size 256
The buggy address is located 8 bytes inside of
freed 256-byte region [ffff88803d442600, ffff88803d442700)
The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3d442
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88801a00bb40 dead000000000100 dead000000000122
raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 0080000000000040 ffff88801a00bb40 dead000000000100 dead000000000122
head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000
head: 0080000000000001 ffffffffffffff81 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4960, tgid 4960 (udevd), ts 172905709445, free_ts 172859766288
set_page_owner include/linux/page_owner.h:32 [inline]
post_alloc_hook+0x231/0x280 mm/page_alloc.c:1858
prep_new_page mm/page_alloc.c:1866 [inline]
get_page_from_freelist+0x27c8/0x2840 mm/page_alloc.c:3946
__alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5226
alloc_slab_page mm/slub.c:3278 [inline]
allocate_slab+0x77/0x660 mm/slub.c:3467
new_slab mm/slub.c:3525 [inline]
refill_objects+0x33c/0x3d0 mm/slub.c:7255
refill_sheaf mm/slub.c:2816 [inline]
__pcs_replace_empty_main+0x373/0x720 mm/slub.c:4651
alloc_from_pcs mm/slub.c:4749 [inline]
slab_alloc_node mm/slub.c:4883 [inline]
__kmalloc_cache_noprof+0x44e/0x690 mm/slub.c:5414
kmalloc_noprof include/linux/slab.h:950 [inline]
kzalloc_noprof include/linux/slab.h:1188 [inline]
smk_fetch+0x95/0x140 security/smack/smack_lsm.c:285
smack_d_instantiate+0x89c/0x990 security/smack/smack_lsm.c:3688
security_d_instantiate+0x106/0x1d0 security/security.c:3704
d_splice_alias_ops+0x71/0x3e0 fs/dcache.c:3141
__lookup_slow+0x2d2/0x440 fs/namei.c:1915
lookup_slow+0x53/0x70 fs/namei.c:1932
walk_component fs/namei.c:2278 [inline]
link_path_walk+0xd1e/0x18d0 fs/namei.c:2652
path_openat+0x2d5/0x38a0 fs/namei.c:4854
do_file_open+0x23e/0x4a0 fs/namei.c:4887
page last free pid 6638 tgid 6638 stack trace:
reset_page_owner include/linux/page_owner.h:25 [inline]
__free_pages_prepare mm/page_alloc.c:1402 [inline]
__free_frozen_pages+0xfa6/0x10f0 mm/page_alloc.c:2943
__slab_free+0x252/0x2a0 mm/slub.c:5612
qlink_free mm/kasan/quarantine.c:163 [inline]
qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179
kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286
__kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350
kasan_slab_alloc include/linux/kasan.h:253 [inline]
slab_post_alloc_hook mm/slub.c:4569 [inline]
slab_alloc_node mm/slub.c:4898 [inline]
kmem_cache_alloc_noprof+0x33b/0x680 mm/slub.c:4905
vm_area_dup+0x2b/0x670 mm/vma_init.c:123
__split_vma+0x1e4/0xa30 mm/vma.c:516
split_vma mm/vma.c:599 [inline]
vma_modify+0x9f9/0x1f20 mm/vma.c:1699
vma_modify_flags+0x24b/0x330 mm/vma.c:1719
mprotect_fixup+0x62a/0xb60 mm/mprotect.c:789
do_mprotect_pkey+0x8d5/0xd20 mm/mprotect.c:967
__do_sys_mprotect mm/mprotect.c:988 [inline]
__se_sys_mprotect mm/mprotect.c:985 [inline]
__x64_sys_mprotect+0x80/0x90 mm/mprotect.c:985
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f
Memory state around the buggy address:
ffff88803d442500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
ffff88803d442580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88803d442600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88803d442680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88803d442700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================
Tested on:
commit: c7e4e4d5 Merge tag 'for-linus-7.1-2' of https://github..
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=115a7b48580000
kernel config: https://syzkaller.appspot.com/x/.config?x=f2e8ebfec4636d32
dashboard link: https://syzkaller.appspot.com/bug?extid=885a4f3281b8d99c48d8
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
patch: https://syzkaller.appspot.com/x/patch.diff?x=13f76696580000
^ permalink raw reply [flat|nested] 4+ messages in thread
* Re: [syzbot] KASAN: use-after-free Read in jfs_lazycommit
@ 2024-10-13 3:29 Qianqiang Liu
2024-10-13 4:49 ` [syzbot] [jfs?] " syzbot
0 siblings, 1 reply; 4+ messages in thread
From: Qianqiang Liu @ 2024-10-13 3:29 UTC (permalink / raw)
To: syzbot; +Cc: jfs-discussion, linux-kernel, shaggy, syzkaller-bugs
#syz test
diff --git a/fs/jfs/jfs_incore.h b/fs/jfs/jfs_incore.h
index 10934f9a11be..7b75c801b239 100644
--- a/fs/jfs/jfs_incore.h
+++ b/fs/jfs/jfs_incore.h
@@ -177,11 +177,6 @@ struct jfs_sb_info {
pxd_t ait2; /* pxd describing AIT copy */
uuid_t uuid; /* 128-bit uuid for volume */
uuid_t loguuid; /* 128-bit uuid for log */
- /*
- * commit_state is used for synchronization of the jfs_commit
- * threads. It is protected by LAZY_LOCK().
- */
- int commit_state; /* commit state */
/* Formerly in ipimap */
uint gengen; /* inode generation generator*/
uint inostamp; /* shows inode belongs to fileset*/
@@ -199,9 +194,6 @@ struct jfs_sb_info {
uint minblks_trim; /* minimum blocks, for online trim */
};
-/* jfs_sb_info commit_state */
-#define IN_LAZYCOMMIT 1
-
static inline struct jfs_inode_info *JFS_IP(struct inode *inode)
{
return container_of(inode, struct jfs_inode_info, vfs_inode);
diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c
index be17e3c43582..a4817229d573 100644
--- a/fs/jfs/jfs_txnmgr.c
+++ b/fs/jfs/jfs_txnmgr.c
@@ -2700,7 +2700,6 @@ int jfs_lazycommit(void *arg)
int WorkDone;
struct tblock *tblk;
unsigned long flags;
- struct jfs_sb_info *sbi;
set_freezable();
do {
@@ -2711,17 +2710,16 @@ int jfs_lazycommit(void *arg)
list_for_each_entry(tblk, &TxAnchor.unlock_queue,
cqueue) {
- sbi = JFS_SBI(tblk->sb);
/*
* For each volume, the transactions must be
* handled in order. If another commit thread
* is handling a tblk for this superblock,
* skip it
*/
- if (sbi->commit_state & IN_LAZYCOMMIT)
+ if (tblk->commit_state & IN_LAZYCOMMIT)
continue;
- sbi->commit_state |= IN_LAZYCOMMIT;
+ tblk->commit_state |= IN_LAZYCOMMIT;
WorkDone = 1;
/*
@@ -2733,7 +2731,7 @@ int jfs_lazycommit(void *arg)
txLazyCommit(tblk);
LAZY_LOCK(flags);
- sbi->commit_state &= ~IN_LAZYCOMMIT;
+ tblk->commit_state &= ~IN_LAZYCOMMIT;
/*
* Don't continue in the for loop. (We can't
* anyway, it's unsafe!) We want to go back to
@@ -2781,7 +2779,7 @@ void txLazyUnlock(struct tblock * tblk)
* Don't wake up a commit thread if there is already one servicing
* this superblock, or if the last one we woke up hasn't started yet.
*/
- if (!(JFS_SBI(tblk->sb)->commit_state & IN_LAZYCOMMIT) &&
+ if (!(tblk->commit_state & IN_LAZYCOMMIT) &&
!jfs_commit_thread_waking) {
jfs_commit_thread_waking = 1;
wake_up(&jfs_commit_thread_wait);
diff --git a/fs/jfs/jfs_txnmgr.h b/fs/jfs/jfs_txnmgr.h
index ba71eb5ced56..3a0ee53f17cb 100644
--- a/fs/jfs/jfs_txnmgr.h
+++ b/fs/jfs/jfs_txnmgr.h
@@ -32,6 +32,11 @@ struct tblock {
/* lock management */
struct super_block *sb; /* super block */
+ /*
+ * commit_state is used for synchronization of the jfs_commit
+ * threads. It is protected by LAZY_LOCK().
+ */
+ int commit_state; /* commit state */
lid_t next; /* index of first tlock of tid */
lid_t last; /* index of last tlock of tid */
wait_queue_head_t waitor; /* tids waiting on this tid */
@@ -56,6 +61,9 @@ struct tblock {
u32 ino; /* inode number being created */
};
+/* tblock commit_state */
+#define IN_LAZYCOMMIT 1
+
extern struct tblock *TxBlock; /* transaction block table */
/* commit flags: tblk->xflag */
--
Best,
Qianqiang Liu
^ permalink raw reply related [flat|nested] 4+ messages in thread
end of thread, other threads:[~2026-05-05 13:26 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
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[not found] <177759080895.1633114.18321249853733805964@gmail.com>
2026-05-04 21:58 ` [syzbot] [jfs?] KASAN: use-after-free Read in jfs_lazycommit syzbot
[not found] <69f9e3be.050a0220.c7d39.a142@mx.google.com>
2026-05-05 13:26 ` syzbot
[not found] <177793457212.208789.6662052297059821760@gmail.com>
2026-05-04 23:23 ` syzbot
2024-10-13 3:29 [syzbot] " Qianqiang Liu
2024-10-13 4:49 ` [syzbot] [jfs?] " syzbot
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