================================================================== BUG: KASAN: slab-use-after-free in __list_lru_walk_one+0xfb/0x420 mm/list_lru.c:293 Read of size 8 at addr ffff888058263318 by task syz.9.1774/13836 CPU: 0 UID: 0 PID: 13836 Comm: syz.9.1774 Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xca/0x240 mm/kasan/report.c:482 kasan_report+0x118/0x150 mm/kasan/report.c:595 __list_lru_walk_one+0xfb/0x420 mm/list_lru.c:293 list_lru_walk_one+0x3c/0x50 mm/list_lru.c:341 list_lru_shrink_walk include/linux/list_lru.h:262 [inline] gfs2_qd_shrink_scan+0x155/0x330 fs/gfs2/quota.c:182 do_shrink_slab+0x6df/0x10d0 mm/shrinker.c:437 shrink_slab+0xd74/0x10d0 mm/shrinker.c:664 drop_slab_node mm/vmscan.c:434 [inline] drop_slab+0x14b/0x290 mm/vmscan.c:452 drop_caches_sysctl_handler+0xc7/0x170 fs/drop_caches.c:68 proc_sys_call_handler+0x4cb/0x700 fs/proc/proc_sysctl.c:600 iter_file_splice_write+0x972/0x10b0 fs/splice.c:738 do_splice_from fs/splice.c:938 [inline] direct_splice_actor+0x101/0x160 fs/splice.c:1161 splice_direct_to_actor+0x5a8/0xcc0 fs/splice.c:1105 do_splice_direct_actor fs/splice.c:1204 [inline] do_splice_direct+0x181/0x270 fs/splice.c:1230 do_sendfile+0x4da/0x7e0 fs/read_write.c:1370 __do_sys_sendfile64 fs/read_write.c:1425 [inline] __se_sys_sendfile64+0xd9/0x190 fs/read_write.c:1417 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f0621b8f749 Code: ff ff c3 66 2e 0f 1f 84 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 RSP: 002b:00007f0622a6f038 EFLAGS: 00000246 ORIG_RAX: 0000000000000028 RAX: ffffffffffffffda RBX: 00007f0621de6090 RCX: 00007f0621b8f749 RDX: 0000200000002080 RSI: 0000000000000004 RDI: 0000000000000005 RBP: 00007f0621c13f91 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000021c R11: 0000000000000246 R12: 0000000000000000 R13: 00007f0621de6128 R14: 00007f0621de6090 R15: 00007ffd4e29f358 Allocated by task 12569: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 unpoison_slab_object mm/kasan/common.c:339 [inline] __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:365 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4948 [inline] slab_alloc_node mm/slub.c:5258 [inline] kmem_cache_alloc_noprof+0x37d/0x710 mm/slub.c:5265 qd_alloc+0x50/0x250 fs/gfs2/quota.c:234 gfs2_quota_init+0x762/0x1200 fs/gfs2/quota.c:1448 gfs2_make_fs_rw+0x143/0x220 fs/gfs2/super.c:149 gfs2_fill_super+0x1b6a/0x21b0 fs/gfs2/ops_fstype.c:1275 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691 gfs2_get_tree+0x51/0x1e0 fs/gfs2/ops_fstype.c:1332 vfs_get_tree+0x92/0x2a0 fs/super.c:1751 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3636 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3712 do_mount fs/namespace.c:4035 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4201 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 23: kasan_save_stack mm/kasan/common.c:56 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:77 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:252 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284 kasan_slab_free include/linux/kasan.h:234 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6663 [inline] kmem_cache_free+0x197/0x620 mm/slub.c:6774 gfs2_qd_dealloc+0x70/0xe0 fs/gfs2/quota.c:111 rcu_do_batch kernel/rcu/tree.c:2605 [inline] rcu_core+0xd70/0x1870 kernel/rcu/tree.c:2857 handle_softirqs+0x27d/0x850 kernel/softirq.c:622 run_ksoftirqd+0x9b/0x100 kernel/softirq.c:1063 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160 kthread+0x711/0x8a0 kernel/kthread.c:463 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:56 kasan_record_aux_stack+0xbd/0xd0 mm/kasan/generic.c:556 __call_rcu_common kernel/rcu/tree.c:3119 [inline] call_rcu+0x157/0x9c0 kernel/rcu/tree.c:3239 qd_ungrab_sync fs/gfs2/quota.c:493 [inline] gfs2_quota_sync+0x30c/0x460 fs/gfs2/quota.c:1351 gfs2_sync_fs+0x4c/0xb0 fs/gfs2/super.c:658 sync_filesystem+0xee/0x230 fs/sync.c:56 generic_shutdown_super+0x6f/0x2c0 fs/super.c:622 kill_block_super+0x44/0x90 fs/super.c:1722 deactivate_locked_super+0xbc/0x130 fs/super.c:474 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1318 task_work_run+0x1d4/0x260 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:44 [inline] exit_to_user_mode_loop+0xff/0x4f0 kernel/entry/common.c:75 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode_work include/linux/entry-common.h:159 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:194 [inline] do_syscall_64+0x2e3/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff8880582632a0 which belongs to the cache gfs2_quotad of size 272 The buggy address is located 120 bytes inside of freed 272-byte region [ffff8880582632a0, ffff8880582633b0) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880582632a0 pfn:0x58263 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff8881442bddc0 dead000000000122 0000000000000000 raw: ffff8880582632a0 00000000800c0009 00000000f5000000 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Reclaimable, gfp_mask 0x52c50(GFP_NOFS|__GFP_RECLAIMABLE|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 6629, tgid 6628 (syz.5.172), ts 141847183197, free_ts 26289285860 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x234/0x290 mm/page_alloc.c:1846 prep_new_page mm/page_alloc.c:1854 [inline] get_page_from_freelist+0x2365/0x2440 mm/page_alloc.c:3915 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5210 alloc_pages_mpol+0x232/0x4a0 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3b0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xf2b/0x1960 mm/slub.c:4651 __slab_alloc+0x65/0x100 mm/slub.c:4774 __slab_alloc_node mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:5246 [inline] kmem_cache_alloc_noprof+0x40f/0x710 mm/slub.c:5265 qd_alloc+0x50/0x250 fs/gfs2/quota.c:234 gfs2_quota_init+0x762/0x1200 fs/gfs2/quota.c:1448 gfs2_make_fs_rw+0x143/0x220 fs/gfs2/super.c:149 gfs2_fill_super+0x1b6a/0x21b0 fs/gfs2/ops_fstype.c:1275 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691 gfs2_get_tree+0x51/0x1e0 fs/gfs2/ops_fstype.c:1332 vfs_get_tree+0x92/0x2a0 fs/super.c:1751 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3636 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3712 page last free pid 1 tgid 1 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1395 [inline] __free_frozen_pages+0xbc8/0xd30 mm/page_alloc.c:2943 __free_pages mm/page_alloc.c:5329 [inline] free_contig_range+0x1bd/0x490 mm/page_alloc.c:7197 destroy_args+0x69/0x660 mm/debug_vm_pgtable.c:983 debug_vm_pgtable+0x38f/0x3a0 mm/debug_vm_pgtable.c:1372 do_one_initcall+0x1fb/0x820 init/main.c:1378 do_initcall_level+0x104/0x190 init/main.c:1440 do_initcalls+0x59/0xa0 init/main.c:1456 kernel_init_freeable+0x334/0x4b0 init/main.c:1688 kernel_init+0x1d/0x1d0 init/main.c:1578 ret_from_fork+0x599/0xb30 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Memory state around the buggy address: ffff888058263200: fb fb fb fb fb fb fb fb fb fb fb fb fc fc fc fc ffff888058263280: fc fc fc fc fa fb fb fb fb fb fb fb fb fb fb fb >ffff888058263300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888058263380: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ffff888058263400: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================