================================================================== BUG: KASAN: use-after-free in __up_write kernel/locking/rwsem.c:1366 [inline] BUG: KASAN: use-after-free in up_write+0x67/0x420 kernel/locking/rwsem.c:1626 Read of size 8 at addr ffff888070b1b708 by task gfs2_quotad/4997 CPU: 0 PID: 4997 Comm: gfs2_quotad Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 __up_write kernel/locking/rwsem.c:1366 [inline] up_write+0x67/0x420 kernel/locking/rwsem.c:1626 inode_unlock include/linux/fs.h:763 [inline] do_sync+0x931/0xc00 fs/gfs2/quota.c:984 gfs2_quota_sync+0x32c/0x6f0 fs/gfs2/quota.c:1329 quotad_check_timeo fs/gfs2/quota.c:1519 [inline] gfs2_quotad+0x413/0x670 fs/gfs2/quota.c:1566 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 4981: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 __kasan_slab_alloc+0x6b/0x80 mm/kasan/common.c:328 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc_lru+0x11a/0x2e0 mm/slub.c:3390 alloc_inode_sb include/linux/fs.h:3245 [inline] gfs2_alloc_inode+0x50/0x120 fs/gfs2/super.c:1543 alloc_inode fs/inode.c:261 [inline] iget5_locked+0x9e/0x260 fs/inode.c:1328 gfs2_inode_lookup+0xd5/0xc80 fs/gfs2/inode.c:124 gfs2_dir_search+0x165/0x220 fs/gfs2/dir.c:1664 gfs2_lookupi+0x45f/0x640 fs/gfs2/inode.c:323 gfs2_lookup_simple+0xa3/0xf0 fs/gfs2/inode.c:264 init_inodes+0x180/0x320 fs/gfs2/ops_fstype.c:904 gfs2_fill_super+0x1718/0x1f80 fs/gfs2/ops_fstype.c:1246 get_tree_bdev+0x3f1/0x610 fs/super.c:1366 gfs2_get_tree+0x4d/0x1e0 fs/gfs2/ops_fstype.c:1327 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 5020: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] kmem_cache_free+0xf7/0x290 mm/slub.c:3709 rcu_do_batch kernel/rcu/tree.c:2297 [inline] rcu_core+0x9c0/0x16a0 kernel/rcu/tree.c:2557 handle_softirqs+0x2a1/0x920 kernel/softirq.c:596 __do_softirq kernel/softirq.c:630 [inline] invoke_softirq kernel/softirq.c:470 [inline] __irq_exit_rcu+0x12f/0x220 kernel/softirq.c:679 irq_exit_rcu+0x5/0x20 kernel/softirq.c:691 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1118 [inline] sysvec_apic_timer_interrupt+0xa0/0xc0 arch/x86/kernel/apic/apic.c:1118 asm_sysvec_apic_timer_interrupt+0x16/0x20 arch/x86/include/asm/idtentry.h:691 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 call_rcu+0x154/0x980 kernel/rcu/tree.c:2849 destroy_inode fs/inode.c:316 [inline] evict+0x7da/0x870 fs/inode.c:720 gfs2_put_super+0x412/0x8c0 fs/gfs2/super.c:616 generic_shutdown_super+0x130/0x340 fs/super.c:501 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x463/0x4f0 fs/namespace.c:1191 task_work_run+0x1ca/0x250 kernel/task_work.c:203 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888070b1b5c0 which belongs to the cache gfs2_inode of size 1592 The buggy address is located 328 bytes inside of 1592-byte region [ffff888070b1b5c0, ffff888070b1bbf8) The buggy address belongs to the physical page: page:ffffea0001c2c600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x70b18 head:ffffea0001c2c600 order:3 compound_mapcount:0 compound_pincount:0 memcg:ffff888076ddc501 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888147eac000 raw: 0000000000000000 0000000080130013 00000001ffffffff ffff888076ddc501 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Reclaimable, gfp_mask 0x1d20d0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL|__GFP_RECLAIMABLE), pid 4981, tgid 4977 (syz.1.125), ts 96875983467, free_ts 70774159405 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1230 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc_lru+0x1ae/0x2e0 mm/slub.c:3390 alloc_inode_sb include/linux/fs.h:3245 [inline] gfs2_alloc_inode+0x50/0x120 fs/gfs2/super.c:1543 alloc_inode fs/inode.c:261 [inline] iget5_locked+0x9e/0x260 fs/inode.c:1328 gfs2_inode_lookup+0xd5/0xc80 fs/gfs2/inode.c:124 gfs2_lookup_root fs/gfs2/ops_fstype.c:462 [inline] init_sb+0xa2a/0x1310 fs/gfs2/ops_fstype.c:529 gfs2_fill_super+0x13fa/0x1f80 fs/gfs2/ops_fstype.c:1213 get_tree_bdev+0x3f1/0x610 fs/super.c:1366 gfs2_get_tree+0x4d/0x1e0 fs/gfs2/ops_fstype.c:1327 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3078 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare mm/page_alloc.c:1509 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479 free_slab mm/slub.c:2036 [inline] discard_slab mm/slub.c:2042 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2591 put_cpu_partial+0x17c/0x250 mm/slub.c:2667 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] kmem_cache_alloc_node+0x14d/0x320 mm/slub.c:3404 __alloc_skb+0xfc/0x7e0 net/core/skbuff.c:505 alloc_skb include/linux/skbuff.h:1271 [inline] nlmsg_new include/net/netlink.h:991 [inline] br_vlan_notify+0x260/0x750 net/bridge/br_vlan.c:1900 __vlan_add+0x15c2/0x26e0 net/bridge/br_vlan.c:299 nbp_vlan_add+0x25e/0x3b0 net/bridge/br_vlan.c:1341 br_vlan_info+0xf7/0x450 net/bridge/br_netlink.c:689 br_process_vlan_info+0x545/0x7f0 net/bridge/br_netlink.c:752 br_afspec+0x1f6/0x5c0 net/bridge/br_netlink.c:820 Memory state around the buggy address: ffff888070b1b600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888070b1b680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888070b1b700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888070b1b780: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888070b1b800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================