kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 ================================================================== BUG: KASAN: use-after-free in instrument_atomic_read include/linux/instrumented.h:71 [inline] BUG: KASAN: use-after-free in test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] BUG: KASAN: use-after-free in gfs2_withdrawn fs/gfs2/util.h:207 [inline] BUG: KASAN: use-after-free in quotad_error+0x60/0x170 fs/gfs2/quota.c:1506 Read of size 8 at addr ffff8880282400a8 by task gfs2_quotad/4677 CPU: 0 PID: 4677 Comm: gfs2_quotad Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x235/0x290 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:71 [inline] test_bit include/asm-generic/bitops/instrumented-non-atomic.h:134 [inline] gfs2_withdrawn fs/gfs2/util.h:207 [inline] quotad_error+0x60/0x170 fs/gfs2/quota.c:1506 quotad_check_timeo fs/gfs2/quota.c:1520 [inline] gfs2_quotad+0x414/0x890 fs/gfs2/quota.c:1586 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 4663: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:607 [inline] kzalloc include/linux/slab.h:738 [inline] init_sbd fs/gfs2/ops_fstype.c:77 [inline] gfs2_fill_super+0x17d/0x1f00 fs/gfs2/ops_fstype.c:1151 get_tree_bdev+0x3f1/0x610 fs/super.c:1325 gfs2_get_tree+0x4d/0x1e0 fs/gfs2/ops_fstype.c:1332 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x24a/0xa40 fs/namespace.c:3034 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562 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 4188: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kfree+0xef/0x2a0 mm/slub.c:4564 generic_shutdown_super+0x130/0x300 fs/super.c:475 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 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 ffff888028240000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 168 bytes inside of 8192-byte region [ffff888028240000, ffff888028242000) The buggy address belongs to the page: page:ffffea0000a09000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x28240 head:ffffea0000a09000 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888016c42280 raw: 0000000000000000 0000000080020002 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 4663, ts 114930308450, free_ts 110303021078 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501 alloc_slab_page mm/slub.c:1780 [inline] allocate_slab mm/slub.c:1917 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1980 ___slab_alloc+0x80a/0xdd0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc_trace+0x1a5/0x2a0 mm/slub.c:3250 kmalloc include/linux/slab.h:607 [inline] kzalloc include/linux/slab.h:738 [inline] init_sbd fs/gfs2/ops_fstype.c:77 [inline] gfs2_fill_super+0x17d/0x1f00 fs/gfs2/ops_fstype.c:1151 get_tree_bdev+0x3f1/0x610 fs/super.c:1325 gfs2_get_tree+0x4d/0x1e0 fs/gfs2/ops_fstype.c:1332 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x24a/0xa40 fs/namespace.c:3034 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562 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 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396 kasan_depopulate_vmalloc_pte+0x67/0x80 mm/kasan/shadow.c:375 apply_to_pte_range mm/memory.c:2573 [inline] apply_to_pmd_range mm/memory.c:2617 [inline] apply_to_pud_range mm/memory.c:2653 [inline] apply_to_p4d_range mm/memory.c:2689 [inline] __apply_to_page_range+0x983/0xd10 mm/memory.c:2725 kasan_release_vmalloc+0x93/0xb0 mm/kasan/shadow.c:485 __purge_vmap_area_lazy+0xafc/0x1950 mm/vmalloc.c:1711 _vm_unmap_aliases+0x410/0x4a0 mm/vmalloc.c:2114 change_page_attr_set_clr+0x323/0xca0 arch/x86/mm/pat/set_memory.c:1740 change_page_attr_clear arch/x86/mm/pat/set_memory.c:1797 [inline] set_memory_ro+0x89/0xd0 arch/x86/mm/pat/set_memory.c:1943 bpf_jit_binary_lock_ro include/linux/filter.h:919 [inline] bpf_int_jit_compile+0xc6d8/0xcd80 arch/x86/net/bpf_jit_comp.c:2478 bpf_prog_select_runtime+0x46f/0x7c0 kernel/bpf/core.c:1977 bpf_migrate_filter net/core/filter.c:1307 [inline] bpf_prepare_filter+0x1020/0x11d0 net/core/filter.c:1355 bpf_prog_create_from_user+0x2ce/0x420 net/core/filter.c:1449 seccomp_prepare_filter kernel/seccomp.c:669 [inline] seccomp_prepare_user_filter kernel/seccomp.c:706 [inline] seccomp_set_mode_filter kernel/seccomp.c:1834 [inline] do_seccomp+0x814/0x16c0 kernel/seccomp.c:1954 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 Memory state around the buggy address: ffff88802823ff80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888028240000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888028240080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888028240100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888028240180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================