syzbot

 sign-in | mailing list | source | docs
🐞 Open [112]
🐞 Fixed [23]
🐞 Invalid [313]
≡ Crashes
Kernel Health Bugs/Month Bug Lifetimes Fuzzing
💬 Send us feedback

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: 322d, last: 4d21h
▶ ▼ Similar bugs (6)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page 19 118 492d 968d 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) 19 48 1d04h 192d 0/2 premoderation: reported on 2024/12/31 14:15
android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page 19 150 446d 974d 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 19 2 527d 608d 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) 19 1 332d 332d 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 19 143 759d 972d 0/2 auto-obsoleted due to no activity on 2023/08/23 09:09

Sample crash report:
==================================================================
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+0x6f2/0x760 mm/filemap.c:172
Read of size 4 at addr ffff88811a627470 by task kswapd0/46

CPU: 1 PID: 46 Comm: kswapd0 Tainted: G        W         5.15.185-syzkaller-00178-g5cf73bface18 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x30 lib/dump_stack.c:88
 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:427 [inline]
 kasan_report+0xf1/0x140 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+0x6f2/0x760 mm/filemap.c:172
 __delete_from_page_cache+0xbe/0x420 mm/filemap.c:240
 __remove_mapping+0x60b/0x930 mm/vmscan.c:1216
 shrink_page_list+0x2778/0x5040 mm/vmscan.c:1824
 shrink_inactive_list mm/vmscan.c:2331 [inline]
 shrink_list mm/vmscan.c:2576 [inline]
 shrink_lruvec+0x10f3/0x36a0 mm/vmscan.c:5793
 shrink_node_memcgs mm/vmscan.c:5985 [inline]
 shrink_node+0x11e9/0x2a70 mm/vmscan.c:6015
 kswapd_shrink_node mm/vmscan.c:6766 [inline]
 balance_pgdat+0xfba/0x2150 mm/vmscan.c:6956
 kswapd+0x649/0xcf0 mm/vmscan.c:7215
 kthread+0x411/0x500 kernel/kthread.c:337
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
 </TASK>

Allocated by task 7805:
 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 mm/kasan/common.c:512 [inline]
 __kasan_kmalloc+0xda/0x110 mm/kasan/common.c:521
 kasan_kmalloc include/linux/kasan.h:227 [inline]
 __kmalloc_track_caller+0x13c/0x2c0 mm/slub.c:4954
 kmalloc_reserve net/core/skbuff.c:357 [inline]
 __alloc_skb+0x21a/0x740 net/core/skbuff.c:428
 alloc_skb include/linux/skbuff.h:1183 [inline]
 alloc_skb_with_frags+0xa8/0x620 net/core/skbuff.c:6194
 sock_alloc_send_pskb+0x853/0x980 net/core/sock.c:2537
 unix_dgram_sendmsg+0x5ea/0x1880 net/unix/af_unix.c:1805
 sock_sendmsg_nosec net/socket.c:704 [inline]
 __sock_sendmsg net/socket.c:716 [inline]
 ____sys_sendmsg+0x5a2/0x8c0 net/socket.c:2436
 ___sys_sendmsg+0x1f0/0x260 net/socket.c:2490
 __sys_sendmmsg+0x278/0x480 net/socket.c:2576
 __do_sys_sendmmsg net/socket.c:2605 [inline]
 __se_sys_sendmmsg net/socket.c:2602 [inline]
 __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2602
 x64_sys_call+0x6c6/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:308
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

Freed by task 7804:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4a/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x125/0x160 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+0xc2/0x190 mm/slub.c:1749
 slab_free mm/slub.c:3521 [inline]
 kfree+0xc4/0x270 mm/slub.c:4583
 skb_free_head net/core/skbuff.c:656 [inline]
 skb_release_data+0x814/0xa10 net/core/skbuff.c:678
 skb_release_all net/core/skbuff.c:743 [inline]
 __kfree_skb net/core/skbuff.c:757 [inline]
 kfree_skb_reason net/core/skbuff.c:778 [inline]
 kfree_skb+0xb9/0x2f0 net/core/skbuff.c:792
 unix_release_sock+0x854/0xad0 net/unix/af_unix.c:578
 unix_release+0x8c/0xc0 net/unix/af_unix.c:937
 __sock_release net/socket.c:649 [inline]
 sock_close+0xe0/0x270 net/socket.c:1336
 __fput+0x20b/0x8b0 fs/file_table.c:311
 ____fput+0x15/0x20 fs/file_table.c:339
 task_work_run+0x127/0x190 kernel/task_work.c:188
 tracehook_notify_resume include/linux/tracehook.h:189 [inline]
 exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181
 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:214
 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307
 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x66/0xd0

The buggy address belongs to the object at ffff88811a627400
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 112 bytes inside of
 512-byte region [ffff88811a627400, ffff88811a627600)
The buggy address belongs to the page:
page:ffffea0004698900 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11a624
head:ffffea0004698900 order:2 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head|zone=1)
raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100042f00
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 7028, ts 401148293014, free_ts 399716479648
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611
 get_page_from_freelist+0x2cc5/0x2d50 mm/page_alloc.c:4485
 __alloc_pages+0x18f/0x440 mm/page_alloc.c:5795
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1932 [inline]
 new_slab+0xa1/0x4d0 mm/slub.c:1995
 ___slab_alloc+0x381/0x810 mm/slub.c:3028
 __slab_alloc+0x49/0x90 mm/slub.c:3115
 slab_alloc_node mm/slub.c:3206 [inline]
 slab_alloc mm/slub.c:3250 [inline]
 __kmalloc_track_caller+0x169/0x2c0 mm/slub.c:4949
 kmalloc_reserve net/core/skbuff.c:357 [inline]
 __alloc_skb+0x21a/0x740 net/core/skbuff.c:428
 alloc_skb include/linux/skbuff.h:1183 [inline]
 alloc_skb_with_frags+0xa8/0x620 net/core/skbuff.c:6194
 sock_alloc_send_pskb+0x853/0x980 net/core/sock.c:2537
 sock_alloc_send_skb+0x32/0x40 net/core/sock.c:2554
 __ip_append_data+0x1f27/0x3190 net/ipv4/ip_output.c:1102
 ip_make_skb+0x1cc/0x3d0 net/ipv4/ip_output.c:1647
 udp_sendmsg+0x1708/0x20b0 net/ipv4/udp.c:1274
 inet_sendmsg+0xa5/0xc0 net/ipv4/af_inet.c:830
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+0x542/0x550 mm/page_alloc.c:3534
 free_unref_page+0xa2/0x550 mm/page_alloc.c:3616
 free_the_page mm/page_alloc.c:805 [inline]
 __free_pages+0x6c/0x100 mm/page_alloc.c:5871
 __free_slab+0xe8/0x1e0 mm/slub.c:2020
 free_slab mm/slub.c:2035 [inline]
 discard_slab mm/slub.c:2041 [inline]
 __unfreeze_partials+0x160/0x190 mm/slub.c:2527
 put_cpu_partial+0xc6/0x120 mm/slub.c:2607
 __slab_free+0x1d4/0x290 mm/slub.c:3390
 do_slab_free mm/slub.c:3509 [inline]
 ___cache_free+0x104/0x120 mm/slub.c:3530
 qlink_free+0x4d/0x90 mm/kasan/quarantine.c:157
 qlist_free_all+0x5f/0xb0 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x14a/0x170 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xf0 mm/kasan/common.c:443
 kasan_slab_alloc include/linux/kasan.h:217 [inline]
 slab_post_alloc_hook+0x4f/0x2b0 mm/slab.h:550
 slab_alloc_node mm/slub.c:3240 [inline]
 slab_alloc mm/slub.c:3250 [inline]
 kmem_cache_alloc+0xf7/0x260 mm/slub.c:3255
 kmem_cache_alloc_node include/linux/slab.h:489 [inline]
 __alloc_skb+0xe0/0x740 net/core/skbuff.c:416
 alloc_skb include/linux/skbuff.h:1183 [inline]
 alloc_skb_with_frags+0xa8/0x620 net/core/skbuff.c:6194

Memory state around the buggy address:
 ffff88811a627300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff88811a627380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff88811a627400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff88811a627480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88811a627500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (39):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/07/07 00:37 android13-5.15-lts 5cf73bface18 4f67c4ae .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/06/30 01:47 android13-5.15-lts 0d918fa8e88d fc9d8ee5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/06/20 00:57 android13-5.15-lts e678c93d43cc ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/06/20 00:30 android13-5.15-lts e678c93d43cc ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/06/20 00:26 android13-5.15-lts e678c93d43cc ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/06/19 11:31 android13-5.15-lts e678c93d43cc ed3e87f7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/06/17 21:09 android13-5.15-lts e678c93d43cc e77fae15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/06/09 05:32 android13-5.15-lts e678c93d43cc 4826c28e .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/05/29 21:26 android13-5.15-lts 4032a894ccb2 3d2f584d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/05/19 07:47 android13-5.15-lts 57725b368731 f41472b0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/05/11 07:58 android13-5.15-lts f93c8b5a9e60 77908e5f .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/05/08 09:12 android13-5.15-lts 57b1420d5e49 dbf35fa1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/05/04 20:48 android13-5.15-lts 88c4075c39ed b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/05/04 12:48 android13-5.15-lts 88c4075c39ed b0714e37 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/05/02 08:03 android13-5.15-lts 88c4075c39ed 51b137cd .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/04/27 21:53 android13-5.15-lts 8034ec1338e8 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/04/21 16:22 android13-5.15-lts 8034ec1338e8 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/04/14 12:38 android13-5.15-lts a8a88afaecee 0bd6db41 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/31 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
2025/06/20 00:36 android13-5.15-lts e678c93d43cc ed3e87f7 .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
2025/06/13 11:17 android13-5.15-lts e678c93d43cc 98683f8f .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
2025/06/13 03:37 android13-5.15-lts e678c93d43cc 98683f8f .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
2025/06/10 07:33 android13-5.15-lts e678c93d43cc 4826c28e .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
2025/04/04 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.