================================================================== BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline] BUG: KASAN: use-after-free in atomic_long_read include/linux/atomic/atomic-instrumented.h:1183 [inline] BUG: KASAN: use-after-free in __down_read_trylock kernel/locking/rwsem.c:1321 [inline] BUG: KASAN: use-after-free in down_read_trylock+0x7c/0x300 kernel/locking/rwsem.c:1588 Read of size 8 at addr ffff88811745f070 by task kworker/u4:2/45 CPU: 1 PID: 45 Comm: kworker/u4:2 Not tainted 5.15.148-syzkaller-1069047-g993bed180178 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024 Workqueue: writeback wb_workfn (flush-7:3) Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x151/0x1b7 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 kasan_check_range+0x293/0x2a0 mm/kasan/generic.c:189 __kasan_check_read+0x11/0x20 mm/kasan/shadow.c:31 instrument_atomic_read include/linux/instrumented.h:71 [inline] atomic_long_read include/linux/atomic/atomic-instrumented.h:1183 [inline] __down_read_trylock kernel/locking/rwsem.c:1321 [inline] down_read_trylock+0x7c/0x300 kernel/locking/rwsem.c:1588 trylock_super+0x1f/0xf0 fs/super.c:418 __writeback_inodes_wb+0x101/0x3f0 fs/fs-writeback.c:1992 wb_writeback+0x3cd/0x9e0 fs/fs-writeback.c:2106 wb_check_background_flush fs/fs-writeback.c:2172 [inline] wb_do_writeback fs/fs-writeback.c:2260 [inline] wb_workfn+0xc12/0x1110 fs/fs-writeback.c:2288 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:298 Allocated by task 383: 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_slab_alloc+0xb1/0xe0 mm/kasan/common.c:466 kasan_slab_alloc include/linux/kasan.h:217 [inline] slab_post_alloc_hook+0x53/0x2c0 mm/slab.h:550 slab_alloc_node mm/slub.c:3240 [inline] slab_alloc mm/slub.c:3248 [inline] kmem_cache_alloc+0xf5/0x200 mm/slub.c:3253 getname_flags+0xba/0x520 fs/namei.c:138 user_path_at_empty+0x2d/0x1a0 fs/namei.c:2882 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xfd/0x720 fs/stat.c:221 vfs_fstatat fs/stat.c:243 [inline] __do_sys_newfstatat fs/stat.c:411 [inline] __se_sys_newfstatat+0xc8/0x760 fs/stat.c:405 __x64_sys_newfstatat+0x9b/0xb0 fs/stat.c:405 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb Freed by task 383: 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:3519 [inline] kmem_cache_free+0x116/0x2e0 mm/slub.c:3535 putname fs/namei.c:271 [inline] user_path_at_empty+0x14e/0x1a0 fs/namei.c:2885 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xfd/0x720 fs/stat.c:221 vfs_fstatat fs/stat.c:243 [inline] __do_sys_newfstatat fs/stat.c:411 [inline] __se_sys_newfstatat+0xc8/0x760 fs/stat.c:405 __x64_sys_newfstatat+0x9b/0xb0 fs/stat.c:405 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb The buggy address belongs to the object at ffff88811745e600 which belongs to the cache names_cache of size 4096 The buggy address is located 2672 bytes inside of 4096-byte region [ffff88811745e600, ffff88811745f600) The buggy address belongs to the page: page:ffffea00045d1600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x117458 head:ffffea00045d1600 order:3 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head|zone=1) raw: 4000000000010200 0000000000000000 dead000000000122 ffff8881001be180 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 383, ts 122196907087, free_ts 122127597766 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1a3/0x1b0 mm/page_alloc.c:2604 prep_new_page+0x1b/0x110 mm/page_alloc.c:2610 get_page_from_freelist+0x3550/0x35d0 mm/page_alloc.c:4484 __alloc_pages+0x27e/0x8f0 mm/page_alloc.c:5776 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:3248 [inline] kmem_cache_alloc+0x134/0x200 mm/slub.c:3253 getname_flags+0xba/0x520 fs/namei.c:138 user_path_at_empty+0x2d/0x1a0 fs/namei.c:2882 user_path_at include/linux/namei.h:57 [inline] vfs_statx+0xfd/0x720 fs/stat.c:221 vfs_fstatat fs/stat.c:243 [inline] __do_sys_newfstatat fs/stat.c:411 [inline] __se_sys_newfstatat+0xc8/0x760 fs/stat.c:405 __x64_sys_newfstatat+0x9b/0xb0 fs/stat.c:405 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x61/0xcb page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1471 [inline] free_pcp_prepare mm/page_alloc.c:1543 [inline] free_unref_page_prepare+0x7c8/0x7d0 mm/page_alloc.c:3533 free_unref_page+0xe8/0x750 mm/page_alloc.c:3615 free_the_page mm/page_alloc.c:804 [inline] __free_pages+0x61/0xf0 mm/page_alloc.c:5852 __free_slab+0xec/0x1d0 mm/slub.c:2020 free_slab mm/slub.c:2035 [inline] discard_slab mm/slub.c:2041 [inline] __unfreeze_partials+0x165/0x1a0 mm/slub.c:2527 put_cpu_partial+0xc4/0x120 mm/slub.c:2607 __slab_free+0x1c8/0x290 mm/slub.c:3388 do_slab_free mm/slub.c:3507 [inline] ___cache_free+0x109/0x120 mm/slub.c:3526 qlink_free+0x4d/0x90 mm/kasan/quarantine.c:157 qlist_free_all+0x44/0xb0 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x15a/0x180 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xe0 mm/kasan/common.c:443 kasan_slab_alloc include/linux/kasan.h:217 [inline] slab_post_alloc_hook+0x53/0x2c0 mm/slab.h:550 slab_alloc_node mm/slub.c:3240 [inline] slab_alloc mm/slub.c:3248 [inline] kmem_cache_alloc+0xf5/0x200 mm/slub.c:3253 getname_flags+0xba/0x520 fs/namei.c:138 user_path_at_empty+0x2d/0x1a0 fs/namei.c:2882 Memory state around the buggy address: ffff88811745ef00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811745ef80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88811745f000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88811745f080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88811745f100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================