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KASAN: use-after-free Read in unaccount_page_cache_page (3)

Status: premoderation: reported on 2024/12/31 14:15
Reported-by: syzbot+29b5af9192239d0a42cc@syzkaller.appspotmail.com
First crash: 118d, last: 13h05m
▶ ▼ 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 418d 893d 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 150 372d 900d 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 453d 534d 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 257d 257d 0/2 auto-obsoleted due to no activity on 2024/11/11 21:33
android-5-15 KASAN: use-after-free Read in unaccount_page_cache_page (2) 20 19h47m 248d 0/2 premoderation: reported on 2024/08/23 02:36
android-54 KASAN: use-after-free Read in unaccount_page_cache_page 143 684d 898d 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+0x9e0/0xac0 mm/filemap.c:175
Read of size 4 at addr ffff888115634470 by task syz.4.6712/26467

CPU: 1 PID: 26467 Comm: syz.4.6712 Tainted: G        W         5.10.236-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Call Trace:
 __dump_stack+0x21/0x24 lib/dump_stack.c:77
 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:435 [inline]
 kasan_report+0xe2/0x130 mm/kasan/report.c:452
 __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+0x9e0/0xac0 mm/filemap.c:175
 __delete_from_page_cache+0xc4/0x460 mm/filemap.c:243
 __remove_mapping+0x562/0x690 mm/vmscan.c:985
 shrink_page_list+0x2109/0x4120 mm/vmscan.c:1498
 shrink_inactive_list+0x4f4/0xe80 mm/vmscan.c:2075
 shrink_list mm/vmscan.c:2294 [inline]
 shrink_lruvec+0x2246/0x2770 mm/vmscan.c:5473
 shrink_node_memcgs mm/vmscan.c:5660 [inline]
 shrink_node+0xf0c/0x2690 mm/vmscan.c:5690
 shrink_zones mm/vmscan.c:5896 [inline]
 do_try_to_free_pages+0x5db/0x1560 mm/vmscan.c:5954
 try_to_free_mem_cgroup_pages+0x233/0x5b0 mm/vmscan.c:6272
 try_charge+0x42b/0x14e0 mm/memcontrol.c:2747
 __mem_cgroup_charge+0x14c/0x6d0 mm/memcontrol.c:6873
 mem_cgroup_charge include/linux/memcontrol.h:458 [inline]
 shmem_add_to_page_cache+0x55e/0xe10 mm/shmem.c:699
 shmem_getpage_gfp+0x8e8/0x2110 mm/shmem.c:1952
 shmem_getpage mm/shmem.c:161 [inline]
 shmem_write_begin+0xce/0x1b0 mm/shmem.c:2497
 generic_perform_write+0x2be/0x510 mm/filemap.c:3509
 __generic_file_write_iter+0x24b/0x480 mm/filemap.c:3638
 generic_file_write_iter+0xa9/0x1d0 mm/filemap.c:3670
 __kernel_write+0x55a/0x910 fs/read_write.c:550
 dump_emit+0x240/0x360 fs/coredump.c:849
 dump_user_range+0x6a/0x1a0 fs/coredump.c:902
 elf_core_dump+0x278a/0x2bc0 fs/binfmt_elf.c:2290
 do_coredump+0x1ac9/0x27f0 fs/coredump.c:811
 get_signal+0xf23/0x12e0 kernel/signal.c:2779
 arch_do_signal_or_restart+0xbf/0x10f0 arch/x86/kernel/signal.c:805
 handle_signal_work kernel/entry/common.c:145 [inline]
 exit_to_user_mode_loop+0xa2/0xe0 kernel/entry/common.c:169
 exit_to_user_mode_prepare kernel/entry/common.c:199 [inline]
 irqentry_exit_to_user_mode+0x4e/0x80 kernel/entry/common.c:287
 irqentry_exit+0x12/0x60 kernel/entry/common.c:375
 exc_page_fault+0x67/0xc0 arch/x86/mm/fault.c:1487
 asm_exc_page_fault+0x1e/0x30 arch/x86/include/asm/idtentry.h:571
RIP: 0033:0x7f863741d971
Code: 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 83 c8 ff c3 66 2e 0f 1f
RSP: 002b:00000000fffffe10 EFLAGS: 00010217
RAX: 0000000000000000 RBX: 00007f8637644fa0 RCX: 00007f863741d969
RDX: 0000000000000000 RSI: 00000000fffffe10 RDI: 0000000000000000
RBP: 00007f863749fab1 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 0000000000000001 R14: 00007f8637644fa0 R15: 00007ffee6b9c538

Allocated by task 20331:
 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:430 [inline]
 __kasan_slab_alloc+0xbd/0xf0 mm/kasan/common.c:463
 kasan_slab_alloc include/linux/kasan.h:244 [inline]
 slab_post_alloc_hook+0x5d/0x2f0 mm/slab.h:583
 slab_alloc_node mm/slub.c:2947 [inline]
 slab_alloc mm/slub.c:2955 [inline]
 kmem_cache_alloc+0x165/0x2e0 mm/slub.c:2960
 getname_flags+0xb9/0x500 fs/namei.c:141
 getname fs/namei.c:212 [inline]
 __do_sys_unlinkat fs/namei.c:-1 [inline]
 __se_sys_unlinkat fs/namei.c:4070 [inline]
 __x64_sys_unlinkat+0xb0/0xf0 fs/namei.c:4070
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Freed by task 20331:
 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:362
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370
 kasan_slab_free include/linux/kasan.h:220 [inline]
 slab_free_hook mm/slub.c:1595 [inline]
 slab_free_freelist_hook+0xc5/0x190 mm/slub.c:1621
 slab_free mm/slub.c:3203 [inline]
 kmem_cache_free+0x100/0x2d0 mm/slub.c:3219
 putname fs/namei.c:262 [inline]
 do_rmdir+0x55a/0x620 fs/namei.c:3924
 __do_sys_unlinkat fs/namei.c:4076 [inline]
 __se_sys_unlinkat fs/namei.c:4070 [inline]
 __x64_sys_unlinkat+0xc7/0xf0 fs/namei.c:4070
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

The buggy address belongs to the object at ffff888115634400
 which belongs to the cache names_cache of size 4096
The buggy address is located 112 bytes inside of
 4096-byte region [ffff888115634400, ffff888115635400)
The buggy address belongs to the page:
page:ffffea0004558c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x115630
head:ffffea0004558c00 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head)
raw: 4000000000010200 dead000000000100 dead000000000122 ffff88810018b800
raw: 0000000000000000 0000000000070007 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 8358, ts 883628904533, free_ts 883542233964
 set_page_owner include/linux/page_owner.h:35 [inline]
 post_alloc_hook mm/page_alloc.c:2456 [inline]
 prep_new_page+0x179/0x180 mm/page_alloc.c:2462
 get_page_from_freelist+0x2235/0x23d0 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x268/0x5f0 mm/page_alloc.c:5349
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1808 [inline]
 new_slab+0x84/0x3f0 mm/slub.c:1869
 new_slab_objects mm/slub.c:2627 [inline]
 ___slab_alloc+0x2a6/0x450 mm/slub.c:2791
 __slab_alloc+0x63/0xa0 mm/slub.c:2831
 slab_alloc_node mm/slub.c:2913 [inline]
 slab_alloc mm/slub.c:2955 [inline]
 kmem_cache_alloc+0x1af/0x2e0 mm/slub.c:2960
 getname_flags+0xb9/0x500 fs/namei.c:141
 getname+0x19/0x20 fs/namei.c:212
 do_sys_openat2+0xd9/0x6d0 fs/open.c:1211
 do_sys_open fs/open.c:1233 [inline]
 __do_sys_openat fs/open.c:1249 [inline]
 __se_sys_openat fs/open.c:1244 [inline]
 __x64_sys_openat+0x136/0x160 fs/open.c:1244
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:28 [inline]
 free_pages_prepare mm/page_alloc.c:1349 [inline]
 __free_pages_ok+0x7fc/0x820 mm/page_alloc.c:1629
 free_the_page mm/page_alloc.c:5410 [inline]
 __free_pages+0xdd/0x380 mm/page_alloc.c:5419
 __free_slab+0xcf/0x190 mm/slub.c:1894
 free_slab mm/slub.c:1909 [inline]
 discard_slab mm/slub.c:1915 [inline]
 unfreeze_partials+0x15f/0x190 mm/slub.c:2410
 put_cpu_partial+0xc1/0x180 mm/slub.c:2446
 __slab_free+0x2c9/0x3a0 mm/slub.c:3095
 do_slab_free mm/slub.c:3191 [inline]
 ___cache_free+0x111/0x130 mm/slub.c:3210
 qlink_free+0x50/0x90 mm/kasan/quarantine.c:157
 qlist_free_all+0x5f/0xb0 mm/kasan/quarantine.c:176
 kasan_quarantine_reduce+0x14a/0x160 mm/kasan/quarantine.c:283
 __kasan_slab_alloc+0x2f/0xf0 mm/kasan/common.c:440
 kasan_slab_alloc include/linux/kasan.h:244 [inline]
 slab_post_alloc_hook+0x5d/0x2f0 mm/slab.h:583
 slab_alloc_node mm/slub.c:2947 [inline]
 slab_alloc mm/slub.c:2955 [inline]
 kmem_cache_alloc+0x165/0x2e0 mm/slub.c:2960
 getname_flags+0xb9/0x500 fs/namei.c:141
 user_path_at_empty+0x2f/0x50 fs/namei.c:2740
 user_path_at include/linux/namei.h:60 [inline]
 vfs_statx+0xff/0x520 fs/stat.c:193

Memory state around the buggy address:
 ffff888115634300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888115634380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888115634400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                             ^
 ffff888115634480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888115634500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================

Crashes (29):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/04/28 04:35 android13-5.10-lts ba8b8b193394 c6b4fb39 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/04/22 15:35 android13-5.10-lts ba8b8b193394 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/04/20 17:49 android13-5.10-lts ba8b8b193394 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/04/19 19:54 android13-5.10-lts ba8b8b193394 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/31 14:38 android13-5.10-lts 094fc3778d6b d3999433 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/29 11:47 android13-5.10-lts 094fc3778d6b cf25e2c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/25 03:23 android13-5.10-lts 094fc3778d6b 875573af .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/24 16:36 android13-5.10-lts 094fc3778d6b 875573af .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/17 04:00 android13-5.10-lts fc9aa81462ee e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/16 15:58 android13-5.10-lts fc9aa81462ee e2826670 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/12 08:44 android13-5.10-lts 3f5f2283d684 ee70e6db .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/04 12:36 android13-5.10-lts 3f5f2283d684 c3901742 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/03/03 21:52 android13-5.10-lts 3f5f2283d684 c3901742 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/02/13 11:22 android13-5.10-lts 6686f2996d23 b27c2402 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/02/09 17:46 android13-5.10-lts 6686f2996d23 ef44b750 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/01/27 00:30 android13-5.10-lts fbe98d68b6b3 9fbd772e .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/01/04 23:44 android13-5.10-lts 49e8ba0a684f f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/01/01 22:13 android13-5.10-lts 49e8ba0a684f d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2024/12/31 14:14 android13-5.10-lts 49e8ba0a684f d3ccff63 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: use-after-free Read in unaccount_page_cache_page
2025/04/19 15:02 android13-5.10-lts ba8b8b193394 2a20f901 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2025/04/01 09:19 android13-5.10-lts 094fc3778d6b 36d76a97 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2025/03/31 00:35 android13-5.10-lts 094fc3778d6b d3999433 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2025/03/13 02:18 android13-5.10-lts 3f5f2283d684 1a5d9317 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2025/03/08 21:03 android13-5.10-lts 3f5f2283d684 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2025/03/08 15:46 android13-5.10-lts 3f5f2283d684 7e3bd60d .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2025/03/03 15:57 android13-5.10-lts 3f5f2283d684 c3901742 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2025/03/03 15:32 android13-5.10-lts 3f5f2283d684 c3901742 .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2025/01/19 04:48 android13-5.10-lts fbe98d68b6b3 f2cb035c .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
2025/01/04 23:21 android13-5.10-lts 49e8ba0a684f f3558dbf .config console log report info [disk image] [vmlinux] [kernel image] ci2-android-5-10 KASAN: slab-out-of-bounds Read in unaccount_page_cache_page
* Struck through repros no longer work on HEAD.