================================================================== BUG: KASAN: use-after-free in ext4_xattr_delete_inode+0xc67/0xc80 fs/ext4/xattr.c:2900 Read of size 4 at addr ffff888123584000 by task syz-executor/488 CPU: 0 PID: 488 Comm: syz-executor Not tainted 5.10.234-syzkaller-1006652-g3f5f2283d684 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack_lvl+0x1e2/0x24b lib/dump_stack.c:118 print_address_description+0x81/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:435 [inline] kasan_report+0x179/0x1c0 mm/kasan/report.c:452 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 ext4_xattr_delete_inode+0xc67/0xc80 fs/ext4/xattr.c:2900 ext4_evict_inode+0x1095/0x1730 fs/ext4/inode.c:300 evict+0x526/0x9c0 fs/inode.c:612 iput_final fs/inode.c:1736 [inline] iput+0x632/0x7e0 fs/inode.c:1762 d_delete_notify include/linux/fsnotify.h:267 [inline] vfs_rmdir+0x271/0x3f0 fs/namei.c:3865 do_rmdir+0x2cf/0x5c0 fs/namei.c:3912 __do_sys_unlinkat fs/namei.c:4076 [inline] __se_sys_unlinkat fs/namei.c:4070 [inline] __x64_sys_unlinkat+0xdf/0xf0 fs/namei.c:4070 do_syscall_64+0x34/0x70 entry_SYSCALL_64_after_hwframe+0x61/0xcb RIP: 0033:0x7f77f86b2167 Code: 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 07 01 00 00 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:00007ffcaedab468 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f77f86b2167 RDX: 0000000000000200 RSI: 00007ffcaedac610 RDI: 00000000ffffff9c RBP: 00007f77f872064a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000207 R12: 00007ffcaedac610 R13: 00007f77f872064a R14: 000000000000c5c8 R15: 00007ffcaedae7f0 Allocated by task 0: (stack is not available) Freed by task 111: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x121/0x160 mm/kasan/common.c:362 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:370 kasan_slab_free include/linux/kasan.h:220 [inline] slab_free_hook mm/slub.c:1595 [inline] slab_free_freelist_hook+0xc0/0x190 mm/slub.c:1621 slab_free mm/slub.c:3203 [inline] kfree+0xc3/0x270 mm/slub.c:4191 skb_free_head net/core/skbuff.c:606 [inline] skb_release_data+0x5c6/0x6f0 net/core/skbuff.c:626 skb_release_all net/core/skbuff.c:680 [inline] __kfree_skb net/core/skbuff.c:694 [inline] consume_skb+0xac/0x250 net/core/skbuff.c:851 netlink_broadcast_filtered+0x114e/0x1270 net/netlink/af_netlink.c:1517 netlink_broadcast net/netlink/af_netlink.c:1539 [inline] nlmsg_multicast include/net/netlink.h:1033 [inline] nlmsg_notify+0x101/0x1c0 net/netlink/af_netlink.c:2528 rtnl_notify+0x9c/0xd0 net/core/rtnetlink.c:737 inet6_ifa_notify net/ipv6/addrconf.c:5533 [inline] __ipv6_ifa_notify+0x32a/0x11c0 net/ipv6/addrconf.c:6132 addrconf_ifdown+0xe14/0x1a60 net/ipv6/addrconf.c:3908 addrconf_notify+0x378/0xe90 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x8c/0xf0 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2054 [inline] call_netdevice_notifiers_extack net/core/dev.c:2066 [inline] call_netdevice_notifiers net/core/dev.c:2080 [inline] dev_close_many+0x37f/0x530 net/core/dev.c:1655 unregister_netdevice_many+0x492/0x17d0 net/core/dev.c:10743 default_device_exit_batch+0x38a/0x3f0 net/core/dev.c:11286 ops_exit_list net/core/net_namespace.c:190 [inline] cleanup_net+0x6e9/0xcb0 net/core/net_namespace.c:609 process_one_work+0x6dc/0xbd0 kernel/workqueue.c:2301 worker_thread+0xaea/0x1510 kernel/workqueue.c:2447 kthread+0x34b/0x3d0 kernel/kthread.c:313 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298 The buggy address belongs to the object at ffff888123584000 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 0 bytes inside of 512-byte region [ffff888123584000, ffff888123584200) The buggy address belongs to the page: page:ffffea00048d6100 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x123584 head:ffffea00048d6100 order:2 compound_mapcount:0 compound_pincount:0 flags: 0x4000000000010200(slab|head) raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100043080 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 2, migratetype Unmovable, gfp_mask 0x1d2a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 111, ts 50376241460, free_ts 50034515123 set_page_owner include/linux/page_owner.h:35 [inline] post_alloc_hook mm/page_alloc.c:2456 [inline] prep_new_page+0x166/0x180 mm/page_alloc.c:2462 get_page_from_freelist+0x2d8c/0x2f30 mm/page_alloc.c:4254 __alloc_pages_nodemask+0x435/0xaf0 mm/page_alloc.c:5348 allocate_slab mm/slub.c:1808 [inline] new_slab+0x80/0x400 mm/slub.c:1869 new_slab_objects mm/slub.c:2627 [inline] ___slab_alloc+0x302/0x4b0 mm/slub.c:2791 __slab_alloc+0x63/0xa0 mm/slub.c:2831 slab_alloc_node mm/slub.c:2913 [inline] slab_alloc mm/slub.c:2955 [inline] __kmalloc_track_caller+0x1f8/0x320 mm/slub.c:4536 __kmalloc_reserve net/core/skbuff.c:144 [inline] __alloc_skb+0xbc/0x510 net/core/skbuff.c:212 alloc_skb include/linux/skbuff.h:1126 [inline] nlmsg_new include/net/netlink.h:953 [inline] inet6_ifa_notify net/ipv6/addrconf.c:5522 [inline] __ipv6_ifa_notify+0x2e1/0x11c0 net/ipv6/addrconf.c:6132 addrconf_ifdown+0xe14/0x1a60 net/ipv6/addrconf.c:3908 addrconf_notify+0x378/0xe90 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x8c/0xf0 kernel/notifier.c:410 call_netdevice_notifiers_info net/core/dev.c:2054 [inline] call_netdevice_notifiers_extack net/core/dev.c:2066 [inline] call_netdevice_notifiers net/core/dev.c:2080 [inline] dev_close_many+0x37f/0x530 net/core/dev.c:1655 unregister_netdevice_many+0x492/0x17d0 net/core/dev.c:10743 default_device_exit_batch+0x38a/0x3f0 net/core/dev.c:11286 ops_exit_list net/core/net_namespace.c:190 [inline] cleanup_net+0x6e9/0xcb0 net/core/net_namespace.c:609 page last free stack trace: reset_page_owner include/linux/page_owner.h:28 [inline] free_pages_prepare mm/page_alloc.c:1349 [inline] free_pcp_prepare mm/page_alloc.c:1421 [inline] free_unref_page_prepare+0x2ae/0x2d0 mm/page_alloc.c:3336 free_unref_page mm/page_alloc.c:3391 [inline] free_the_page+0x9e/0x370 mm/page_alloc.c:5407 __free_pages+0x67/0xc0 mm/page_alloc.c:5418 __vunmap+0x7c1/0x940 mm/vmalloc.c:2301 __vfree mm/vmalloc.c:2350 [inline] vfree+0x5c/0x80 mm/vmalloc.c:2381 kcov_put kernel/kcov.c:408 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:510 __fput+0x33d/0x7b0 fs/file_table.c:281 ____fput+0x15/0x20 fs/file_table.c:314 task_work_run+0x129/0x190 kernel/task_work.c:189 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xc83/0x2a50 kernel/exit.c:863 do_group_exit+0x141/0x310 kernel/exit.c:985 get_signal+0x10a0/0x1410 kernel/signal.c:2793 arch_do_signal_or_restart+0xbd/0x17c0 arch/x86/kernel/signal.c:805 handle_signal_work kernel/entry/common.c:145 [inline] exit_to_user_mode_loop+0x9b/0xd0 kernel/entry/common.c:169 exit_to_user_mode_prepare kernel/entry/common.c:199 [inline] syscall_exit_to_user_mode+0xa2/0x1a0 kernel/entry/common.c:274 do_syscall_64+0x40/0x70 arch/x86/entry/common.c:56 Memory state around the buggy address: ffff888123583f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888123583f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888123584000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888123584080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888123584100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================