================================================================== BUG: KASAN: use-after-free in instrument_atomic_read_write include/linux/instrumented.h:101 [inline] BUG: KASAN: use-after-free in atomic_dec include/linux/atomic/atomic-instrumented.h:244 [inline] BUG: KASAN: use-after-free in gfs2_qd_dispose fs/gfs2/quota.c:137 [inline] BUG: KASAN: use-after-free in gfs2_qd_shrink_scan+0x56c/0x7b0 fs/gfs2/quota.c:175 Write of size 4 at addr ffff0000da850a70 by task syz.2.5642/16683 CPU: 0 PID: 16683 Comm: syz.2.5642 Not tainted 5.15.185-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025 Call trace: dump_backtrace+0x0/0x43c arch/arm64/kernel/stacktrace.c:152 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:216 __dump_stack+0x30/0x40 lib/dump_stack.c:88 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106 print_address_description+0x78/0x30c mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xec/0x15c mm/kasan/report.c:451 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x270/0x2b0 mm/kasan/generic.c:189 __kasan_check_write+0x44/0x54 mm/kasan/shadow.c:37 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic_dec include/linux/atomic/atomic-instrumented.h:244 [inline] gfs2_qd_dispose fs/gfs2/quota.c:137 [inline] gfs2_qd_shrink_scan+0x56c/0x7b0 fs/gfs2/quota.c:175 do_shrink_slab+0x4c0/0xfb8 mm/vmscan.c:765 shrink_slab+0x190/0x6fc mm/vmscan.c:925 drop_slab_node+0xcc/0x170 mm/vmscan.c:960 drop_slab+0x84/0xf8 mm/vmscan.c:970 drop_caches_sysctl_handler+0x16c/0x2fc fs/drop_caches.c:66 proc_sys_call_handler+0x3fc/0x69c fs/proc/proc_sysctl.c:588 proc_sys_write+0x2c/0x3c fs/proc/proc_sysctl.c:614 do_iter_readv_writev+0x3a0/0x4f8 fs/read_write.c:-1 do_iter_write+0x1c4/0x670 fs/read_write.c:855 vfs_writev fs/read_write.c:928 [inline] do_writev+0x1e0/0x380 fs/read_write.c:971 __do_sys_writev fs/read_write.c:1044 [inline] __se_sys_writev fs/read_write.c:1041 [inline] __arm64_sys_writev+0x80/0x94 fs/read_write.c:1041 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Allocated by task 16362: 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+0xb0/0xf0 mm/kasan/common.c:522 kasan_kmalloc include/linux/kasan.h:264 [inline] kmem_cache_alloc_trace+0x274/0x3fc mm/slub.c:3247 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:735 [inline] init_sbd fs/gfs2/ops_fstype.c:77 [inline] gfs2_fill_super+0x118/0x19e0 fs/gfs2/ops_fstype.c:1151 get_tree_bdev+0x358/0x544 fs/super.c:1325 gfs2_get_tree+0x54/0x1b4 fs/gfs2/ops_fstype.c:1332 vfs_get_tree+0x90/0x274 fs/super.c:1530 do_new_mount+0x228/0x810 fs/namespace.c:3010 path_mount+0x5b4/0x1000 fs/namespace.c:3340 do_mount fs/namespace.c:3353 [inline] __do_sys_mount fs/namespace.c:3561 [inline] __se_sys_mount fs/namespace.c:3538 [inline] __arm64_sys_mount+0x514/0x5e4 fs/namespace.c:3538 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:52 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x58/0x14c arch/arm64/kernel/syscall.c:181 el0_svc+0x78/0x1e0 arch/arm64/kernel/entry-common.c:608 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Freed by task 4036: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4c/0x84 mm/kasan/common.c:46 kasan_set_free_info+0x28/0x4c mm/kasan/generic.c:360 ____kasan_slab_free+0x118/0x164 mm/kasan/common.c:366 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:374 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1705 [inline] slab_free_freelist_hook+0x128/0x1e8 mm/slub.c:1731 slab_free mm/slub.c:3499 [inline] kfree+0x170/0x40c mm/slub.c:4559 free_sbd+0x5c/0x6c fs/gfs2/ops_fstype.c:69 gfs2_put_super+0x63c/0x6bc fs/gfs2/super.c:632 generic_shutdown_super+0x130/0x2f0 fs/super.c:475 kill_block_super+0x70/0xdc fs/super.c:1427 gfs2_kill_sb+0xc0/0xd4 fs/gfs2/ops_fstype.c:-1 deactivate_locked_super+0xb8/0x13c fs/super.c:335 deactivate_super+0xf8/0x118 fs/super.c:366 cleanup_mnt+0x3a4/0x458 fs/namespace.c:1139 __cleanup_mnt+0x20/0x30 fs/namespace.c:1146 task_work_run+0x12c/0x1e0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] do_notify_resume+0x24b4/0x3128 arch/arm64/kernel/signal.c:949 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xf0/0x1e0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 Last potentially related work creation: kasan_save_stack+0x38/0x68 mm/kasan/common.c:38 kasan_record_aux_stack+0xcc/0x114 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3007 [inline] call_rcu+0x110/0x8f0 kernel/rcu/tree.c:3087 fat_put_super+0x98/0xac fs/fat/inode.c:740 generic_shutdown_super+0x130/0x2f0 fs/super.c:475 kill_block_super+0x70/0xdc fs/super.c:1427 deactivate_locked_super+0xb8/0x13c fs/super.c:335 deactivate_super+0xf8/0x118 fs/super.c:366 cleanup_mnt+0x3a4/0x458 fs/namespace.c:1139 __cleanup_mnt+0x20/0x30 fs/namespace.c:1146 task_work_run+0x12c/0x1e0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] do_notify_resume+0x24b4/0x3128 arch/arm64/kernel/signal.c:949 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:133 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:138 [inline] el0_svc+0xf0/0x1e0 arch/arm64/kernel/entry-common.c:609 el0t_64_sync_handler+0xcc/0xe4 arch/arm64/kernel/entry-common.c:626 el0t_64_sync+0x1a0/0x1a4 arch/arm64/kernel/entry.S:584 The buggy address belongs to the object at ffff0000da850000 which belongs to the cache kmalloc-8k of size 8192 The buggy address is located 2672 bytes inside of 8192-byte region [ffff0000da850000, ffff0000da852000) The buggy address belongs to the page: page:00000000ffe33aad refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x11a850 head:00000000ffe33aad order:3 compound_mapcount:0 compound_pincount:0 flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff) raw: 05ffc00000010200 0000000000000000 0000000100000001 ffff0000c0002c00 raw: 0000000000000000 0000000000020002 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000da850900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000da850980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000da850a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000da850a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000da850b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== syz.2.5642 (16683): drop_caches: 2