================================================================== BUG: KASAN: use-after-free in ext4_xattr_delete_inode+0xc67/0xc80 fs/ext4/xattr.c:2900 Read of size 4 at addr ffff888115d6a000 by task syz-executor/497 CPU: 0 PID: 497 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: 0033:0x7fd3121dc887 Code: 73 01 c3 48 c7 c1 b0 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffd56d0c7b8 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007fd3121dc887 RDX: 0000000000000200 RSI: 00007ffd56d0d960 RDI: 00000000ffffff9c RBP: 00007fd3122396c6 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000207 R12: 00007ffd56d0d960 R13: 00007fd3122396c6 R14: 000000000000babc R15: 0000000000000000 Allocated by task 106: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:45 [inline] set_alloc_info mm/kasan/common.c:430 [inline] __kasan_slab_alloc+0xb1/0xe0 mm/kasan/common.c:463 kasan_slab_alloc include/linux/kasan.h:244 [inline] slab_post_alloc_hook+0x61/0x2f0 mm/slab.h:583 slab_alloc_node mm/slub.c:2947 [inline] slab_alloc mm/slub.c:2955 [inline] kmem_cache_alloc+0x168/0x2e0 mm/slub.c:2960 kmem_cache_alloc_node include/linux/slab.h:423 [inline] __alloc_skb+0x80/0x510 net/core/skbuff.c:200 alloc_skb include/linux/skbuff.h:1126 [inline] alloc_skb_with_frags+0xa1/0x570 net/core/skbuff.c:5993 sock_alloc_send_pskb+0x915/0xa50 net/core/sock.c:2388 unix_dgram_sendmsg+0x700/0x1f90 net/unix/af_unix.c:1725 sock_sendmsg_nosec net/socket.c:652 [inline] __sock_sendmsg net/socket.c:664 [inline] sock_write_iter+0x39b/0x530 net/socket.c:1018 call_write_iter include/linux/fs.h:2058 [inline] new_sync_write fs/read_write.c:518 [inline] vfs_write+0xb4c/0xe70 fs/read_write.c:605 ksys_write+0x199/0x2c0 fs/read_write.c:658 __do_sys_write fs/read_write.c:670 [inline] __se_sys_write fs/read_write.c:667 [inline] __x64_sys_write+0x7b/0x90 fs/read_write.c:667 do_syscall_64+0x34/0x70 entry_SYSCALL_64_after_hwframe+0x61/0xcb The buggy address belongs to the object at ffff888115d6a000 which belongs to the cache skbuff_head_cache of size 248 The buggy address is located 0 bytes inside of 248-byte region [ffff888115d6a000, ffff888115d6a0f8) The buggy address belongs to the page: page:ffffea0004575a80 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x115d6a flags: 0x4000000000000200(slab) raw: 4000000000000200 ffffea0004577a80 0000000200000002 ffff888107d95c80 raw: 0000000000000000 00000000800c000c 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 0, migratetype Unmovable, gfp_mask 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 106, ts 4074944564, free_ts 0 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] kmem_cache_alloc+0x1b9/0x2e0 mm/slub.c:2960 kmem_cache_alloc_node include/linux/slab.h:423 [inline] __alloc_skb+0x80/0x510 net/core/skbuff.c:200 alloc_skb include/linux/skbuff.h:1126 [inline] alloc_skb_with_frags+0xa1/0x570 net/core/skbuff.c:5993 sock_alloc_send_pskb+0x915/0xa50 net/core/sock.c:2388 unix_dgram_sendmsg+0x700/0x1f90 net/unix/af_unix.c:1725 sock_sendmsg_nosec net/socket.c:652 [inline] __sock_sendmsg net/socket.c:664 [inline] sock_write_iter+0x39b/0x530 net/socket.c:1018 call_write_iter include/linux/fs.h:2058 [inline] new_sync_write fs/read_write.c:518 [inline] vfs_write+0xb4c/0xe70 fs/read_write.c:605 ksys_write+0x199/0x2c0 fs/read_write.c:658 __do_sys_write fs/read_write.c:670 [inline] __se_sys_write fs/read_write.c:667 [inline] __x64_sys_write+0x7b/0x90 fs/read_write.c:667 do_syscall_64+0x34/0x70 page_owner free stack trace missing Memory state around the buggy address: ffff888115d69f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff888115d69f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff888115d6a000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888115d6a080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc ffff888115d6a100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ==================================================================