syzbot


KASAN: use-after-free Read in qd_unlock

Status: upstream: reported on 2024/06/24 18:01
Reported-by: syzbot+34d903364cf7e2fd0bce@syzkaller.appspotmail.com
First crash: 75d, last: 67d
Similar bugs (3)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: use-after-free Read in qd_unlock (2) gfs2 C error done 5 385d 614d 23/27 fixed on 2023/10/12 12:47
upstream KASAN: use-after-free Read in qd_unlock gfs2 1 898d 894d 0/27 auto-closed as invalid on 2022/07/22 08:43
linux-5.15 KASAN: use-after-free Read in qd_unlock origin:lts-only C error 11 57d 75d 0/3 upstream: reported C repro on 2024/06/24 17:41

Sample crash report:
RBP: 00007ffc90a3fda0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc90a40e70
R13: 00007fe5eb9e365d R14: 0000000000011377 R15: 0000000000000000
 </TASK>
==================================================================
BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:72 [inline]
BUG: KASAN: use-after-free in _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
BUG: KASAN: use-after-free in qd_unlock+0x30/0x2d0 fs/gfs2/quota.c:501
Read of size 8 at addr ffff8880274c2090 by task syz-executor/3549

CPU: 1 PID: 3549 Comm: syz-executor Not tainted 6.1.96-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
 print_address_description mm/kasan/report.c:284 [inline]
 print_report+0x15f/0x4f0 mm/kasan/report.c:395
 kasan_report+0x136/0x160 mm/kasan/report.c:495
 kasan_check_range+0x27f/0x290 mm/kasan/generic.c:189
 instrument_atomic_read include/linux/instrumented.h:72 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 qd_unlock+0x30/0x2d0 fs/gfs2/quota.c:501
 gfs2_quota_sync+0x6e3/0x810 fs/gfs2/quota.c:1336
 gfs2_sync_fs+0x49/0xb0 fs/gfs2/super.c:648
 sync_filesystem+0xe8/0x220 fs/sync.c:56
 generic_shutdown_super+0x6b/0x340 fs/super.c:474
 kill_block_super+0x7a/0xe0 fs/super.c:1459
 deactivate_locked_super+0xa0/0x110 fs/super.c:332
 cleanup_mnt+0x490/0x520 fs/namespace.c:1186
 task_work_run+0x246/0x300 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fe5eb977247
Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 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 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffc90a3fce8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fe5eb9e365d RCX: 00007fe5eb977247
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffc90a3fda0
RBP: 00007ffc90a3fda0 R08: 0000000000000000 R09: 0000000000000000
R10: 00000000ffffffff R11: 0000000000000246 R12: 00007ffc90a40e70
R13: 00007fe5eb9e365d R14: 0000000000011377 R15: 0000000000000000
 </TASK>

Allocated by task 3651:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 __kasan_slab_alloc+0x65/0x70 mm/kasan/common.c:328
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x10c/0x2d0 mm/slub.c:3422
 kmem_cache_zalloc include/linux/slab.h:682 [inline]
 qd_alloc+0x51/0x250 fs/gfs2/quota.c:216
 gfs2_quota_init+0x7ea/0x1110 fs/gfs2/quota.c:1426
 gfs2_make_fs_rw+0x436/0x5b0 fs/gfs2/super.c:155
 gfs2_fill_super+0x2377/0x26e0 fs/gfs2/ops_fstype.c:1274
 get_tree_bdev+0x3fe/0x620 fs/super.c:1355
 gfs2_get_tree+0x50/0x210 fs/gfs2/ops_fstype.c:1330
 vfs_get_tree+0x88/0x270 fs/super.c:1562
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3051
 do_mount fs/namespace.c:3394 [inline]
 __do_sys_mount fs/namespace.c:3602 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3579
 do_syscall_x64 arch/x86/entry/common.c:51 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

Freed by task 15:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516
 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1724 [inline]
 slab_free_freelist_hook mm/slub.c:1750 [inline]
 slab_free mm/slub.c:3661 [inline]
 kmem_cache_free+0x292/0x510 mm/slub.c:3683
 rcu_do_batch kernel/rcu/tree.c:2296 [inline]
 rcu_core+0xad5/0x1810 kernel/rcu/tree.c:2556
 handle_softirqs+0x2ee/0xa40 kernel/softirq.c:571
 run_ksoftirqd+0xc6/0x120 kernel/softirq.c:938
 smpboot_thread_fn+0x52c/0xa30 kernel/smpboot.c:164
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

Last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:45
 __kasan_record_aux_stack+0xb0/0xc0 mm/kasan/generic.c:486
 call_rcu+0x163/0xa10 kernel/rcu/tree.c:2844
 gfs2_quota_cleanup+0x43e/0x6a0 fs/gfs2/quota.c:1490
 gfs2_make_fs_ro+0x526/0x620 fs/gfs2/super.c:558
 signal_our_withdraw fs/gfs2/util.c:166 [inline]
 gfs2_withdraw+0x61f/0x14b0 fs/gfs2/util.c:351
 gfs2_meta_check_ii+0x6e/0x80 fs/gfs2/util.c:508
 gfs2_metatype_check_i fs/gfs2/util.h:126 [inline]
 gfs2_rgrp_go_instantiate+0x348/0x12f0 fs/gfs2/rgrp.c:1223
 gfs2_instantiate+0x188/0x250 fs/gfs2/glock.c:520
 gfs2_glock_holder_ready fs/gfs2/glock.c:1330 [inline]
 gfs2_glock_wait+0x1db/0x2a0 fs/gfs2/glock.c:1350
 gfs2_glock_nq_init fs/gfs2/glock.h:264 [inline]
 gfs2_inplace_reserve+0x105a/0x3940 fs/gfs2/rgrp.c:2095
 do_sync+0x652/0xc70 fs/gfs2/quota.c:951
 gfs2_quota_sync+0x379/0x810 fs/gfs2/quota.c:1329
 gfs2_sync_fs+0x49/0xb0 fs/gfs2/super.c:648
 sync_filesystem+0xe8/0x220 fs/sync.c:56
 generic_shutdown_super+0x6b/0x340 fs/super.c:474
 kill_block_super+0x7a/0xe0 fs/super.c:1459
 deactivate_locked_super+0xa0/0x110 fs/super.c:332
 cleanup_mnt+0x490/0x520 fs/namespace.c:1186
 task_work_run+0x246/0x300 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop+0xde/0x100 kernel/entry/common.c:177
 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210
 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline]
 syscall_exit_to_user_mode+0x60/0x270 kernel/entry/common.c:303
 do_syscall_64+0x47/0xb0 arch/x86/entry/common.c:87
 entry_SYSCALL_64_after_hwframe+0x68/0xd2

The buggy address belongs to the object at ffff8880274c2000
 which belongs to the cache gfs2_quotad of size 272
The buggy address is located 144 bytes inside of
 272-byte region [ffff8880274c2000, ffff8880274c2110)

The buggy address belongs to the physical page:
page:ffffea00009d3080 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x274c2
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 0000000000000000 dead000000000122 ffff888141f38640
raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Reclaimable, gfp_mask 0x112c50(GFP_NOFS|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 3651, tgid 3650 (syz.1.11), ts 73375570827, free_ts 71758255084
 set_page_owner include/linux/page_owner.h:31 [inline]
 post_alloc_hook+0x18d/0x1b0 mm/page_alloc.c:2513
 prep_new_page mm/page_alloc.c:2520 [inline]
 get_page_from_freelist+0x31a1/0x3320 mm/page_alloc.c:4279
 __alloc_pages+0x28d/0x770 mm/page_alloc.c:5547
 alloc_slab_page+0x6a/0x150 mm/slub.c:1794
 allocate_slab mm/slub.c:1939 [inline]
 new_slab+0x84/0x2d0 mm/slub.c:1992
 ___slab_alloc+0xc20/0x1270 mm/slub.c:3180
 __slab_alloc mm/slub.c:3279 [inline]
 slab_alloc_node mm/slub.c:3364 [inline]
 slab_alloc mm/slub.c:3406 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3413 [inline]
 kmem_cache_alloc+0x1a5/0x2d0 mm/slub.c:3422
 kmem_cache_zalloc include/linux/slab.h:682 [inline]
 qd_alloc+0x51/0x250 fs/gfs2/quota.c:216
 gfs2_quota_init+0x7ea/0x1110 fs/gfs2/quota.c:1426
 gfs2_make_fs_rw+0x436/0x5b0 fs/gfs2/super.c:155
 gfs2_fill_super+0x2377/0x26e0 fs/gfs2/ops_fstype.c:1274
 get_tree_bdev+0x3fe/0x620 fs/super.c:1355
 gfs2_get_tree+0x50/0x210 fs/gfs2/ops_fstype.c:1330
 vfs_get_tree+0x88/0x270 fs/super.c:1562
 do_new_mount+0x2ba/0xb40 fs/namespace.c:3051
 do_mount fs/namespace.c:3394 [inline]
 __do_sys_mount fs/namespace.c:3602 [inline]
 __se_sys_mount+0x2d5/0x3c0 fs/namespace.c:3579
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1440 [inline]
 free_pcp_prepare mm/page_alloc.c:1490 [inline]
 free_unref_page_prepare+0xf63/0x1120 mm/page_alloc.c:3358
 free_unref_page+0x33/0x3e0 mm/page_alloc.c:3453
 free_slab mm/slub.c:2031 [inline]
 discard_slab mm/slub.c:2037 [inline]
 __unfreeze_partials+0x1b7/0x210 mm/slub.c:2586
 put_cpu_partial+0x17b/0x250 mm/slub.c:2662
 qlink_free mm/kasan/quarantine.c:168 [inline]
 qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187
 kasan_quarantine_reduce+0x156/0x170 mm/kasan/quarantine.c:294
 __kasan_slab_alloc+0x1f/0x70 mm/kasan/common.c:305
 kasan_slab_alloc include/linux/kasan.h:201 [inline]
 slab_post_alloc_hook+0x52/0x3a0 mm/slab.h:737
 slab_alloc_node mm/slub.c:3398 [inline]
 __kmem_cache_alloc_node+0x137/0x260 mm/slub.c:3437
 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1045
 kmalloc include/linux/slab.h:556 [inline]
 kzalloc include/linux/slab.h:692 [inline]
 nsim_fib6_rt_create drivers/net/netdevsim/fib.c:547 [inline]
 nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:752 [inline]
 nsim_fib6_event drivers/net/netdevsim/fib.c:856 [inline]
 nsim_fib_event drivers/net/netdevsim/fib.c:889 [inline]
 nsim_fib_event_work+0x19be/0x4120 drivers/net/netdevsim/fib.c:1492
 process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
 worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
 kthread+0x28d/0x320 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308

Memory state around the buggy address:
 ffff8880274c1f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880274c2000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880274c2080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                         ^
 ffff8880274c2100: fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff8880274c2180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/07/02 22:13 linux-6.1.y 99e6a620de00 07f0a0a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in qd_unlock
2024/07/02 22:12 linux-6.1.y 99e6a620de00 07f0a0a0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan KASAN: use-after-free Read in qd_unlock
2024/06/26 12:41 linux-6.1.y eb44d83053d6 c6d33a01 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in qd_unlock
2024/06/24 20:11 linux-6.1.y eb44d83053d6 215eef4a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in qd_unlock
2024/06/24 18:04 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in qd_unlock
2024/06/24 18:02 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in qd_unlock
2024/06/24 18:00 linux-6.1.y eb44d83053d6 edc5149a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-6-1-kasan-arm64 KASAN: use-after-free Read in qd_unlock
* Struck through repros no longer work on HEAD.