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KASAN: use-after-free Read in unaccount_page_cache_page (2)

Status: premoderation: reported on 2024/08/23 02:36
Reported-by: syzbot+2660878ed6b4da17c8aa@syzkaller.appspotmail.com
First crash: 230d, last: 6d16h
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page 118 401d 876d 0/2 auto-obsoleted due to no activity on 2024/05/01 01:14
android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page (3) 24 9d16h 100d 0/2 premoderation: reported on 2024/12/31 14:15
android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page 150 354d 882d 0/2 auto-obsoleted due to no activity on 2024/06/10 16:28
android-54 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page 2 435d 517d 0/2 auto-obsoleted due to no activity on 2024/04/30 10:15
android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page (2) 1 240d 240d 0/2 auto-obsoleted due to no activity on 2024/11/11 21:33
android-54 KASAN: use-after-free Read in unaccount_page_cache_page 143 667d 880d 0/2 auto-obsoleted due to no activity on 2023/08/23 09:09

Sample crash report:
ext4 filesystem being mounted at /86/mnt supports timestamps until 2038-01-19 (0x7fffffff)
==================================================================
BUG: KASAN: use-after-free in cleancache_fs_enabled_mapping include/linux/cleancache.h:56 [inline]
BUG: KASAN: use-after-free in cleancache_invalidate_page include/linux/cleancache.h:110 [inline]
BUG: KASAN: use-after-free in unaccount_page_cache_page+0x6d8/0x750 mm/filemap.c:167
Read of size 4 at addr ffff8881301b2470 by task syz.0.448/2303

CPU: 0 PID: 2303 Comm: syz.0.448 Not tainted 5.15.178-syzkaller-00034-g5e1b899f19c3 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x151/0x1c0 lib/dump_stack.c:106
 print_address_description+0x87/0x3b0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0x179/0x1c0 mm/kasan/report.c:444
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308
 cleancache_fs_enabled_mapping include/linux/cleancache.h:56 [inline]
 cleancache_invalidate_page include/linux/cleancache.h:110 [inline]
 unaccount_page_cache_page+0x6d8/0x750 mm/filemap.c:167
 __delete_from_page_cache+0xc6/0x5b0 mm/filemap.c:235
 __remove_mapping+0x566/0x690 mm/vmscan.c:1208
 shrink_page_list+0x2723/0x5c50 mm/vmscan.c:1805
 shrink_inactive_list mm/vmscan.c:2312 [inline]
 shrink_list mm/vmscan.c:2557 [inline]
 shrink_lruvec+0x17ec/0x4580 mm/vmscan.c:5762
 shrink_node_memcgs mm/vmscan.c:5954 [inline]
 shrink_node+0x1083/0x2550 mm/vmscan.c:5984
 shrink_zones mm/vmscan.c:6190 [inline]
 do_try_to_free_pages+0x5c6/0x1600 mm/vmscan.c:6248
 try_to_free_pages+0x3a5/0xd70 mm/vmscan.c:6483
 __perform_reclaim mm/page_alloc.c:4949 [inline]
 __alloc_pages_direct_reclaim mm/page_alloc.c:4972 [inline]
 __alloc_pages_slowpath+0x15fe/0x38e0 mm/page_alloc.c:5396
 __alloc_pages+0x503/0x8f0 mm/page_alloc.c:5793
 __alloc_pages_node include/linux/gfp.h:591 [inline]
 alloc_pages_node include/linux/gfp.h:605 [inline]
 alloc_pages include/linux/gfp.h:618 [inline]
 __get_free_pages+0x10/0x30 mm/page_alloc.c:5817
 io_mem_alloc io_uring/io_uring.c:8875 [inline]
 io_allocate_scq_urings io_uring/io_uring.c:10296 [inline]
 io_uring_create io_uring/io_uring.c:10412 [inline]
 io_uring_setup io_uring/io_uring.c:10502 [inline]
 __do_sys_io_uring_setup io_uring/io_uring.c:10508 [inline]
 __se_sys_io_uring_setup+0x1273/0x3660 io_uring/io_uring.c:10505
 __x64_sys_io_uring_setup+0x5b/0x70 io_uring/io_uring.c:10505
 x64_sys_call+0x8ef/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:426
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7feaf6e08169
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:00007feaf5471fc8 EFLAGS: 00000202 ORIG_RAX: 00000000000001a9
RAX: ffffffffffffffda RBX: 00007feaf7020fa0 RCX: 00007feaf6e08169
RDX: 00002000000001c0 RSI: 0000200000000100 RDI: 000000000000275a
RBP: 0000200000000100 R08: 0000000000000000 R09: 00002000000001c0
R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000000
R13: 0000000000000000 R14: 000000000000275a R15: 00002000000001c0
 </TASK>

Allocated by task 1958:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:433 [inline]
 ____kasan_kmalloc+0xdb/0x110 mm/kasan/common.c:512
 __kasan_kmalloc+0x9/0x10 mm/kasan/common.c:521
 kasan_kmalloc include/linux/kasan.h:227 [inline]
 kmem_cache_alloc_trace+0x11a/0x270 mm/slub.c:3269
 kmalloc include/linux/slab.h:603 [inline]
 kzalloc include/linux/slab.h:733 [inline]
 io_ring_ctx_alloc io_uring/io_uring.c:1296 [inline]
 io_uring_create io_uring/io_uring.c:10396 [inline]
 io_uring_setup io_uring/io_uring.c:10502 [inline]
 __do_sys_io_uring_setup io_uring/io_uring.c:10508 [inline]
 __se_sys_io_uring_setup+0x393/0x3660 io_uring/io_uring.c:10505
 __x64_sys_io_uring_setup+0x5b/0x70 io_uring/io_uring.c:10505
 x64_sys_call+0x8ef/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:426
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 2010:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x126/0x160 mm/kasan/common.c:365
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373
 kasan_slab_free include/linux/kasan.h:193 [inline]
 slab_free_hook mm/slub.c:1723 [inline]
 slab_free_freelist_hook+0xbd/0x190 mm/slub.c:1749
 slab_free mm/slub.c:3521 [inline]
 kfree+0xcc/0x270 mm/slub.c:4583
 io_ring_ctx_free io_uring/io_uring.c:9422 [inline]
 io_ring_exit_work+0x158c/0x16c0 io_uring/io_uring.c:9577
 process_one_work+0x6bb/0xc10 kernel/workqueue.c:2325
 worker_thread+0xad5/0x12a0 kernel/workqueue.c:2472
 kthread+0x421/0x510 kernel/kthread.c:337
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xd3/0xf0 mm/kasan/generic.c:348
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358
 insert_work+0x56/0x320 kernel/workqueue.c:1373
 __queue_work+0x92a/0xcd0 kernel/workqueue.c:1539
 queue_work_on+0x105/0x170 kernel/workqueue.c:1566
 queue_work include/linux/workqueue.h:510 [inline]
 io_ring_ctx_wait_and_kill+0x307/0x360 io_uring/io_uring.c:9634
 io_uring_create io_uring/io_uring.c:10475 [inline]
 io_uring_setup io_uring/io_uring.c:10502 [inline]
 __do_sys_io_uring_setup io_uring/io_uring.c:10508 [inline]
 __se_sys_io_uring_setup+0x19c8/0x3660 io_uring/io_uring.c:10505
 __x64_sys_io_uring_setup+0x5b/0x70 io_uring/io_uring.c:10505
 x64_sys_call+0x8ef/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:426
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Second to last potentially related work creation:
 kasan_save_stack+0x3b/0x60 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xd3/0xf0 mm/kasan/generic.c:348
 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358
 insert_work+0x56/0x320 kernel/workqueue.c:1373
 __queue_work+0x92a/0xcd0 kernel/workqueue.c:1539
 queue_work_on+0x105/0x170 kernel/workqueue.c:1566
 queue_work include/linux/workqueue.h:510 [inline]
 schedule_work include/linux/workqueue.h:571 [inline]
 destroy_super_rcu+0xd1/0xe0 fs/super.c:172
 rcu_do_batch+0x57a/0xc10 kernel/rcu/tree.c:2523
 rcu_core+0x517/0x1020 kernel/rcu/tree.c:2763
 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2776
 handle_softirqs+0x25e/0x5c0 kernel/softirq.c:565
 run_ksoftirqd+0x28/0x40 kernel/softirq.c:941
 smpboot_thread_fn+0x466/0x8d0 kernel/smpboot.c:164
 kthread+0x421/0x510 kernel/kthread.c:337
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

The buggy address belongs to the object at ffff8881301b2000
 which belongs to the cache kmalloc-2k of size 2048
The buggy address is located 1136 bytes inside of
 2048-byte region [ffff8881301b2000, ffff8881301b2800)
The buggy address belongs to the page:
page:ffffea0004c06c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1301b0
head:ffffea0004c06c00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 0000000000000000 0000000100000001 ffff888100043200
raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 505, ts 35592850475, free_ts 29343220660
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1a3/0x1b0 mm/page_alloc.c:2605
 prep_new_page+0x1b/0x110 mm/page_alloc.c:2611
 get_page_from_freelist+0x3550/0x35d0 mm/page_alloc.c:4485
 __alloc_pages+0x27e/0x8f0 mm/page_alloc.c:5780
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1932 [inline]
 new_slab+0x9a/0x4e0 mm/slub.c:1995
 ___slab_alloc+0x39e/0x830 mm/slub.c:3028
 __slab_alloc+0x4a/0x90 mm/slub.c:3115
 slab_alloc_node mm/slub.c:3206 [inline]
 slab_alloc mm/slub.c:3250 [inline]
 kmem_cache_alloc_trace+0x147/0x270 mm/slub.c:3267
 kmalloc include/linux/slab.h:603 [inline]
 kzalloc include/linux/slab.h:733 [inline]
 io_ring_ctx_alloc io_uring/io_uring.c:1296 [inline]
 io_uring_create io_uring/io_uring.c:10396 [inline]
 io_uring_setup io_uring/io_uring.c:10502 [inline]
 __do_sys_io_uring_setup io_uring/io_uring.c:10508 [inline]
 __se_sys_io_uring_setup+0x393/0x3660 io_uring/io_uring.c:10505
 __x64_sys_io_uring_setup+0x5b/0x70 io_uring/io_uring.c:10505
 x64_sys_call+0x8ef/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:426
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1472 [inline]
 free_pcp_prepare mm/page_alloc.c:1544 [inline]
 free_unref_page_prepare+0x7c8/0x7d0 mm/page_alloc.c:3534
 free_unref_page+0xe8/0x750 mm/page_alloc.c:3616
 free_the_page mm/page_alloc.c:805 [inline]
 free_compound_page+0x78/0xa0 mm/page_alloc.c:828
 io_mem_free io_uring/io_uring.c:8868 [inline]
 io_ring_ctx_free io_uring/io_uring.c:9413 [inline]
 io_ring_exit_work+0x104d/0x16c0 io_uring/io_uring.c:9577
 process_one_work+0x6bb/0xc10 kernel/workqueue.c:2325
 worker_thread+0xad5/0x12a0 kernel/workqueue.c:2472
 kthread+0x421/0x510 kernel/kthread.c:337
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287

Memory state around the buggy address:
 ffff8881301b2300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881301b2380: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8881301b2400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff8881301b2480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881301b2500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================
syz.0.448 (2303) used greatest stack depth: 15616 bytes left

Crashes (17):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/03/31 16:58 android13-5.15-lts 5e1b899f19c3 d3999433 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/16 10:12 android13-5.15-lts 7d1f9b5c2ff5 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/15 20:45 android13-5.15-lts 7d1f9b5c2ff5 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/14 00:13 android13-5.15-lts 7d1f9b5c2ff5 e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/02/26 19:01 android13-5.15-lts 7d1f9b5c2ff5 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/02/22 11:15 android13-5.15-lts 058abb720bd1 d34966d1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/02/17 00:04 android13-5.15-lts 058abb720bd1 40a34ec9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/02/09 21:35 android13-5.15-lts 058abb720bd1 ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/01/27 01:16 android13-5.15-lts 829d9f138569 9fbd772e .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/01/08 09:23 android13-5.15-lts 19092c8155b4 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/01/03 17:34 android13-5.15-lts af461d0249a8 f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2024/12/29 04:29 android13-5.15-lts b4bd207b0380 d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2024/11/03 14:24 android13-5.15-lts 5e4635681cf1 f00eed24 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2024/08/23 02:35 android13-5.15-lts 29d153aabd54 ce8a9099 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/04/04 09:35 android13-5.15-lts 5e1b899f19c3 1c4febdb .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2025/02/10 02:06 android13-5.15-lts 058abb720bd1 ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2024/11/25 05:51 android13-5.15-lts 101e665d55a8 68da6d95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
* Struck through repros no longer work on HEAD.