R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff3fbd0600 R13: 00007f8e07013d7d R14: 000000000018d390 R15: 00007fff3fbd0640 gfs2: fsid=syz:syz.0: about to withdraw this file system ================================================================== BUG: KASAN: slab-use-after-free in __list_add_valid_or_report+0x6a/0x130 lib/list_debug.c:32 Read of size 8 at addr ffff88804e2d5078 by task syz-executor/21469 CPU: 1 UID: 0 PID: 21469 Comm: syz-executor Not tainted syzkaller #0 PREEMPT(full) 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_add_valid_or_report+0x6a/0x130 lib/list_debug.c:32 __list_add_valid include/linux/list.h:96 [inline] __list_add include/linux/list.h:158 [inline] list_add_tail include/linux/list.h:191 [inline] list_lru_add+0xf2/0x270 mm/list_lru.c:171 qd_put+0x114/0x190 fs/gfs2/quota.c:342 gfs2_quota_sync+0x3c4/0x460 fs/gfs2/quota.c:1361 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:1328 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 RIP: 0033:0x7f8e06f90a77 Code: a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 0f 1f 44 00 00 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 a8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007fff3fbcf4b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 00007f8e07013d7d RCX: 00007f8e06f90a77 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff3fbcf570 RBP: 00007fff3fbcf570 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000246 R12: 00007fff3fbd0600 R13: 00007f8e07013d7d R14: 000000000018d390 R15: 00007fff3fbd0640 Allocated by task 14517: 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:1209 [inline] do_new_mount_fc fs/namespace.c:3646 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3722 do_mount fs/namespace.c:4045 [inline] __do_sys_mount fs/namespace.c:4234 [inline] __se_sys_mount+0x313/0x410 fs/namespace.c:4211 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 6046: 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:626 do_softirq+0xec/0x180 kernel/softirq.c:523 __local_bh_enable_ip+0x17d/0x1c0 kernel/softirq.c:450 lock_sock include/net/sock.h:1700 [inline] tcp_sock_set_nodelay+0x2a/0x180 net/ipv4/tcp.c:3667 rds_tcp_tune+0xc8/0x8f0 net/rds/tcp.c:497 rds_tcp_conn_path_connect+0x2a1/0x680 net/rds/tcp_connect.c:127 rds_connect_worker+0x1d8/0x290 net/rds/threads.c:176 process_one_work+0x93a/0x15a0 kernel/workqueue.c:3261 process_scheduled_works kernel/workqueue.c:3344 [inline] worker_thread+0x9b0/0xee0 kernel/workqueue.c:3425 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:1328 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 ffff88804e2d5000 which belongs to the cache gfs2_quotad of size 272 The buggy address is located 120 bytes inside of freed 272-byte region [ffff88804e2d5000, ffff88804e2d5110) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff88804e2d5000 pfn:0x4e2d5 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000000 ffff88801d7e5280 dead000000000122 0000000000000000 raw: ffff88804e2d5000 00000000800c000b 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 11242, tgid 11241 (syz.3.1233), ts 606496216304, free_ts 585567596557 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:1209 [inline] do_new_mount_fc fs/namespace.c:3646 [inline] do_new_mount+0x302/0xa10 fs/namespace.c:3722 page last free pid 11022 tgid 11021 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 __slab_free+0x21b/0x2a0 mm/slub.c:5999 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:349 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 ptlock_alloc+0x20/0x70 mm/memory.c:7377 ptlock_init include/linux/mm.h:3285 [inline] pagetable_pte_ctor include/linux/mm.h:3339 [inline] __pte_alloc_one_noprof include/asm-generic/pgalloc.h:79 [inline] pte_alloc_one+0x7a/0x370 arch/x86/mm/pgtable.c:18 do_fault_around mm/memory.c:5707 [inline] do_read_fault mm/memory.c:5746 [inline] do_fault mm/memory.c:5889 [inline] do_pte_missing+0x1162/0x3330 mm/memory.c:4401 handle_pte_fault mm/memory.c:6273 [inline] __handle_mm_fault mm/memory.c:6411 [inline] handle_mm_fault+0x1b26/0x32b0 mm/memory.c:6580 faultin_page mm/gup.c:1126 [inline] __get_user_pages+0x1650/0x29f0 mm/gup.c:1428 populate_vma_page_range+0x29f/0x3a0 mm/gup.c:1860 __mm_populate+0x24c/0x380 mm/gup.c:1963 mm_populate include/linux/mm.h:3706 [inline] vm_mmap_pgoff+0x387/0x4d0 mm/util.c:586 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 Memory state around the buggy address: ffff88804e2d4f00: 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc fc ffff88804e2d4f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88804e2d5000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88804e2d5080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88804e2d5100: fb fb fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================