================================================================== 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 ffff8881164fc470 by task syz.6.4435/15993 CPU: 1 PID: 15993 Comm: syz.6.4435 Tainted: G W 5.10.238-syzkaller-00008-g59e9a7228857 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 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:2745 __mem_cgroup_charge+0x14c/0x6d0 mm/memcontrol.c:6871 mem_cgroup_charge include/linux/memcontrol.h:458 [inline] shmem_add_to_page_cache+0x55e/0xe10 mm/shmem.c:703 shmem_getpage_gfp+0x8e8/0x2110 mm/shmem.c:1956 shmem_getpage mm/shmem.c:165 [inline] shmem_write_begin+0xce/0x1b0 mm/shmem.c:2501 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:855 dump_user_range+0x6a/0x1a0 fs/coredump.c:908 elf_core_dump+0x278a/0x2bc0 fs/binfmt_elf.c:2290 do_coredump+0x1ac9/0x27f0 fs/coredump.c:817 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_general_protection+0x1ca/0x250 arch/x86/kernel/traps.c:557 asm_exc_general_protection+0x1e/0x30 arch/x86/include/asm/idtentry.h:565 RIP: 0033:0x7f33541ba931 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 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f RSP: 002b:0000200000000080 EFLAGS: 00010217 RAX: 0000000000000000 RBX: 00007f33543e2160 RCX: 00007f33541ba929 RDX: 00002000000000c0 RSI: 0000200000000080 RDI: 00000000020a0000 RBP: 00007f335423cb39 R08: 0000200000000140 R09: 0000200000000140 R10: 0000200000000100 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f33543e2160 R15: 00007ffd8e5d6338 Allocated by task 14803: 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 shmem_alloc_inode+0x1a/0x30 mm/shmem.c:3820 alloc_inode fs/inode.c:233 [inline] new_inode_pseudo+0x62/0x210 fs/inode.c:968 new_inode+0x28/0x1e0 fs/inode.c:997 shmem_get_inode+0x34a/0x9d0 mm/shmem.c:2315 shmem_symlink+0x9e/0x500 mm/shmem.c:3122 vfs_symlink+0x380/0x520 fs/namei.c:4099 do_symlinkat+0x103/0x3b0 fs/namei.c:4126 __do_sys_symlinkat fs/namei.c:4140 [inline] __se_sys_symlinkat fs/namei.c:4137 [inline] __x64_sys_symlinkat+0x7b/0x90 fs/namei.c:4137 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 __call_rcu kernel/rcu/tree.c:2976 [inline] call_rcu+0x105/0x1040 kernel/rcu/tree.c:3050 destroy_inode fs/inode.c:288 [inline] evict+0x857/0x910 fs/inode.c:629 iput_final fs/inode.c:1736 [inline] iput+0x638/0x7c0 fs/inode.c:1762 do_unlinkat+0x33f/0x670 fs/namei.c:4042 __do_sys_unlink fs/namei.c:4082 [inline] __se_sys_unlink fs/namei.c:4080 [inline] __x64_sys_unlink+0x49/0x50 fs/namei.c:4080 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 entry_SYSCALL_64_after_hwframe+0x61/0xcb Second to last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:38 __kasan_record_aux_stack+0xd2/0x100 mm/kasan/generic.c:348 kasan_record_aux_stack_noalloc+0xb/0x10 mm/kasan/generic.c:358 __call_rcu kernel/rcu/tree.c:2976 [inline] call_rcu+0x105/0x1040 kernel/rcu/tree.c:3050 destroy_inode fs/inode.c:288 [inline] evict+0x857/0x910 fs/inode.c:629 iput_final fs/inode.c:1736 [inline] iput+0x638/0x7c0 fs/inode.c:1762 d_delete_notify include/linux/fsnotify.h:267 [inline] vfs_rmdir+0x2bd/0x3e0 fs/namei.c:3865 do_rmdir+0x218/0x620 fs/namei.c:3912 __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 ffff8881164fc3a0 which belongs to the cache shmem_inode_cache of size 800 The buggy address is located 208 bytes inside of 800-byte region [ffff8881164fc3a0, ffff8881164fc6c0) The buggy address belongs to the page: page:ffffea0004593f00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff8881164fef20 pfn:0x1164fc head:ffffea0004593f00 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 ffffea0004664c08 ffffea00049cc408 ffff88810018b800 raw: ffff8881164fef20 0000000000110002 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 8686, ts 314575621953, free_ts 314493279305 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:5357 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 shmem_alloc_inode+0x1a/0x30 mm/shmem.c:3820 alloc_inode fs/inode.c:233 [inline] new_inode_pseudo+0x62/0x210 fs/inode.c:968 new_inode+0x28/0x1e0 fs/inode.c:997 shmem_get_inode+0x34a/0x9d0 mm/shmem.c:2315 shmem_symlink+0x9e/0x500 mm/shmem.c:3122 vfs_symlink+0x380/0x520 fs/namei.c:4099 do_symlinkat+0x103/0x3b0 fs/namei.c:4126 __do_sys_symlinkat fs/namei.c:4140 [inline] __se_sys_symlinkat fs/namei.c:4137 [inline] __x64_sys_symlinkat+0x7b/0x90 fs/namei.c:4137 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46 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:5418 [inline] __free_pages+0xdd/0x380 mm/page_alloc.c:5427 __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_trace+0x160/0x2e0 mm/slub.c:2972 kmalloc include/linux/slab.h:552 [inline] p9_client_getattr_dotl+0x5a/0x360 net/9p/client.c:1764 v9fs_inode_from_fid_dotl+0x2c/0x220 fs/9p/vfs_inode_dotl.c:152 v9fs_vfs_lookup+0x2fe/0x3c0 fs/9p/vfs_inode.c:-1 Memory state around the buggy address: ffff8881164fc300: fb fb fb fb fc fc fc fc fc fc fc fc fc fc fc fc ffff8881164fc380: fc fc fc fc fb fb fb fb fb fb fb fb fb fb fb fb >ffff8881164fc400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881164fc480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8881164fc500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================