BUG: KASAN: use-after-free in ext4_xattr_delete_inode+0xba6/0xbb0 fs/ext4/xattr.c:2914
Read of size 4 at addr ffff88812952d000 by task syz-executor/457

CPU: 0 PID: 457 Comm: syz-executor Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 __dump_stack+0x21/0x24 lib/dump_stack.c:88
 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106
 print_address_description+0x71/0x200 mm/kasan/report.c:316
 print_report+0x4a/0x60 mm/kasan/report.c:420
 kasan_report+0x122/0x150 mm/kasan/report.c:524
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:350
 ext4_xattr_delete_inode+0xba6/0xbb0 fs/ext4/xattr.c:2914
 ext4_evict_inode+0xe58/0x1460 fs/ext4/inode.c:296
 evict+0x493/0x890 fs/inode.c:708
 iput_final fs/inode.c:1844 [inline]
 iput+0x620/0x670 fs/inode.c:1870
 d_delete_notify include/linux/fsnotify.h:292 [inline]
 vfs_rmdir+0x3bf/0x500 fs/namei.c:4211
 do_rmdir+0x259/0x6a0 fs/namei.c:4259
 __do_sys_unlinkat fs/namei.c:4439 [inline]
 __se_sys_unlinkat fs/namei.c:4433 [inline]
 __x64_sys_unlinkat+0xc7/0xf0 fs/namei.c:4433
 x64_sys_call+0x79f/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:264
 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
RIP: 0033:0x7f1d00979457
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:00007fff281281f8 EFLAGS: 00000207 ORIG_RAX: 0000000000000107
RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f1d00979457
RDX: 0000000000000200 RSI: 00007fff281293a0 RDI: 00000000ffffff9c
RBP: 00007f1d009e77b4 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000100 R11: 0000000000000207 R12: 00007fff281293a0
R13: 00007f1d009e77b4 R14: 000000000000b4aa R15: 00007fff2812b550
 </TASK>

Allocated by task 19:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_alloc_info+0x25/0x30 mm/kasan/generic.c:505
 __kasan_slab_alloc+0x72/0x80 mm/kasan/common.c:333
 kasan_slab_alloc include/linux/kasan.h:202 [inline]
 slab_post_alloc_hook+0x4f/0x2d0 mm/slab.h:768
 slab_alloc_node mm/slub.c:3382 [inline]
 kmem_cache_alloc_node+0x181/0x340 mm/slub.c:3429
 __alloc_skb+0xea/0x4b0 net/core/skbuff.c:508
 alloc_skb include/linux/skbuff.h:1290 [inline]
 ndisc_alloc_skb net/ipv6/ndisc.c:423 [inline]
 ndisc_ns_create+0x26a/0x940 net/ipv6/ndisc.c:626
 ndisc_send_ns+0xab/0x150 net/ipv6/ndisc.c:668
 addrconf_dad_work+0xa02/0x14b0 net/ipv6/addrconf.c:4245
 process_one_work+0x71f/0xc40 kernel/workqueue.c:2302
 worker_thread+0xa29/0x11f0 kernel/workqueue.c:2449
 kthread+0x281/0x320 kernel/kthread.c:386
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Freed by task 19:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4b/0x70 mm/kasan/common.c:52
 kasan_save_free_info+0x31/0x50 mm/kasan/generic.c:516
 ____kasan_slab_free+0x132/0x180 mm/kasan/common.c:241
 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:249
 kasan_slab_free include/linux/kasan.h:178 [inline]
 slab_free_hook mm/slub.c:1750 [inline]
 slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1776
 slab_free mm/slub.c:3712 [inline]
 kmem_cache_free+0x12d/0x300 mm/slub.c:3737
 kfree_skbmem+0x10c/0x180 net/core/skbuff.c:-1
 __kfree_skb net/core/skbuff.c:874 [inline]
 kfree_skb_reason+0xdc/0x230 net/core/skbuff.c:896
 kfree_skb include/linux/skbuff.h:1239 [inline]
 ip6_mc_input+0x518/0x690 net/ipv6/ip6_input.c:589
 dst_input include/net/dst.h:463 [inline]
 ip6_rcv_finish+0x19e/0x370 net/ipv6/ip6_input.c:79
 NF_HOOK include/linux/netfilter.h:305 [inline]
 ipv6_rcv+0xe9/0x210 net/ipv6/ip6_input.c:310
 __netif_receive_skb_one_core net/core/dev.c:5597 [inline]
 __netif_receive_skb+0xd7/0x2a0 net/core/dev.c:5711
 process_backlog+0x351/0x600 net/core/dev.c:6039
 __napi_poll+0xd0/0x5e0 net/core/dev.c:6606
 napi_poll net/core/dev.c:6673 [inline]
 net_rx_action+0x49b/0xaa0 net/core/dev.c:6787
 handle_softirqs+0x1d7/0x600 kernel/softirq.c:642
 __do_softirq+0xb/0xd kernel/softirq.c:680

The buggy address belongs to the object at ffff88812952d000
 which belongs to the cache skbuff_head_cache of size 256
The buggy address is located 0 bytes inside of
 256-byte region [ffff88812952d000, ffff88812952d100)

The buggy address belongs to the physical page:
page:ffffea0004a54b40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12952d
flags: 0x4000000000000200(slab|zone=1)
raw: 4000000000000200 0000000000000000 dead000000000122 ffff8881001f0f00
raw: 0000000000000000 00000000000c000c 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 0x112cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY), pid 468, tgid 467 (syz.0.15), ts 46281790136, free_ts 46275225222
 set_page_owner include/linux/page_owner.h:33 [inline]
 post_alloc_hook+0x1f5/0x210 mm/page_alloc.c:2643
 prep_new_page+0x1c/0x110 mm/page_alloc.c:2650
 get_page_from_freelist+0x2c7b/0x2cf0 mm/page_alloc.c:4554
 __alloc_pages+0x1c3/0x450 mm/page_alloc.c:5868
 alloc_slab_page+0x6e/0xf0 include/linux/gfp.h:-1
 allocate_slab mm/slub.c:1967 [inline]
 new_slab+0x98/0x3d0 mm/slub.c:2020
 ___slab_alloc+0x6bd/0xb20 mm/slub.c:3177
 __slab_alloc+0x5e/0xa0 mm/slub.c:3263
 slab_alloc_node mm/slub.c:3348 [inline]
 slab_alloc mm/slub.c:3392 [inline]
 __kmem_cache_alloc_lru mm/slub.c:3399 [inline]
 kmem_cache_alloc+0x1b0/0x330 mm/slub.c:3408
 skb_clone+0x1f5/0x380 net/core/skbuff.c:1663
 do_one_broadcast net/netlink/af_netlink.c:1454 [inline]
 netlink_broadcast+0x687/0x1180 net/netlink/af_netlink.c:1520
 uevent_net_broadcast_untagged lib/kobject_uevent.c:331 [inline]
 kobject_uevent_net_broadcast+0x3cb/0x5b0 lib/kobject_uevent.c:409
 kobject_uevent_env+0x54f/0x730 lib/kobject_uevent.c:608
 kobject_uevent+0x1d/0x30 lib/kobject_uevent.c:657
 loop_configure+0x11bd/0x1550 drivers/block/loop.c:1109
 lo_ioctl+0x7e3/0x1dc0 drivers/block/loop.c:-1
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:26 [inline]
 free_pages_prepare mm/page_alloc.c:1551 [inline]
 free_pcp_prepare mm/page_alloc.c:1625 [inline]
 free_unref_page_prepare+0x742/0x750 mm/page_alloc.c:3589
 free_unref_page+0x8f/0x530 mm/page_alloc.c:3687
 free_the_page mm/page_alloc.c:836 [inline]
 __free_pages+0x67/0x100 mm/page_alloc.c:5957
 free_pages+0x82/0x90 mm/page_alloc.c:5968
 tlb_batch_list_free mm/mmu_gather.c:75 [inline]
 tlb_finish_mmu+0x2ba/0x370 mm/mmu_gather.c:364
 unmap_region+0x28d/0x2e0 mm/mmap.c:2418
 do_mas_align_munmap+0xb9b/0x1230 mm/mmap.c:2691
 do_mas_munmap+0x241/0x2b0 mm/mmap.c:2749
 __vm_munmap+0x19f/0x2f0 mm/mmap.c:3048
 __do_sys_munmap mm/mmap.c:3074 [inline]
 __se_sys_munmap mm/mmap.c:3070 [inline]
 __x64_sys_munmap+0x6b/0x80 mm/mmap.c:3070
 x64_sys_call+0x8a/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:12
 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

Memory state around the buggy address:
 ffff88812952cf00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff88812952cf80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff88812952d000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff88812952d080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff88812952d100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
==================================================================
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.
EXT4-fs (loop0): unmounting filesystem.