======================================================
WARNING: the mand mount option is being deprecated and
         will be removed in v5.15!
======================================================
EXT4-fs (loop2): mounted filesystem without journal. Opts: ,errors=continue
==================================================================
BUG: KASAN: use-after-free in ext4_xattr_rehash fs/ext4/xattr.c:3142 [inline]
BUG: KASAN: use-after-free in ext4_xattr_set_entry+0xde3/0x36c0 fs/ext4/xattr.c:1824
Read of size 4 at addr ffff8881104b0004 by task syz.2.17/368

CPU: 1 PID: 368 Comm: syz.2.17 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/18/2025
Call Trace:
 __dump_stack+0x21/0x24 lib/dump_stack.c:77
 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118
 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:435 [inline]
 kasan_report+0xe2/0x130 mm/kasan/report.c:452
 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308
 ext4_xattr_rehash fs/ext4/xattr.c:3142 [inline]
 ext4_xattr_set_entry+0xde3/0x36c0 fs/ext4/xattr.c:1824
 ext4_xattr_block_set+0x4d6/0x2a50 fs/ext4/xattr.c:1927
 ext4_xattr_set_handle+0xbd5/0x12a0 fs/ext4/xattr.c:2412
 ext4_xattr_set+0x1ec/0x320 fs/ext4/xattr.c:2513
 ext4_xattr_trusted_set+0x3b/0x50 fs/ext4/xattr_trusted.c:37
 __vfs_setxattr+0x42a/0x480 fs/xattr.c:177
 __vfs_setxattr_noperm+0x11e/0x4e0 fs/xattr.c:208
 __vfs_setxattr_locked+0x203/0x220 fs/xattr.c:266
 vfs_setxattr+0x8d/0x1c0 fs/xattr.c:283
 setxattr+0x1a9/0x370 fs/xattr.c:548
 path_setxattr+0x110/0x210 fs/xattr.c:567
 __do_sys_lsetxattr fs/xattr.c:589 [inline]
 __se_sys_lsetxattr fs/xattr.c:585 [inline]
 __x64_sys_lsetxattr+0xc2/0xe0 fs/xattr.c:585
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7f9bc601cec9
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 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:00007ffccc0e1af8 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd
RAX: ffffffffffffffda RBX: 00007f9bc6273fa0 RCX: 00007f9bc601cec9
RDX: 0000200000000480 RSI: 00002000000000c0 RDI: 0000200000000100
RBP: 00007f9bc609ff91 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000fe37 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9bc6273fa0 R14: 00007f9bc6273fa0 R15: 0000000000000005

Allocated by task 0:
(stack is not available)

The buggy address belongs to the object at ffff8881104b0000
 which belongs to the cache kmalloc-512 of size 512
The buggy address is located 4 bytes inside of
 512-byte region [ffff8881104b0000, ffff8881104b0200)
The buggy address belongs to the page:
page:ffffea0004412c00 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1104b0
head:ffffea0004412c00 order:2 compound_mapcount:0 compound_pincount:0
flags: 0x4000000000010200(slab|head)
raw: 4000000000010200 dead000000000100 dead000000000122 ffff888100043080
raw: 0000000000000000 0000000080100010 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 100, ts 4367163002, 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+0x179/0x180 mm/page_alloc.c:2462
 get_page_from_freelist+0x2235/0x23d0 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x268/0x5f0 mm/page_alloc.c:5370
 alloc_slab_page mm/slub.c:-1 [inline]
 allocate_slab mm/slub.c:1813 [inline]
 new_slab+0x84/0x3f0 mm/slub.c:1874
 new_slab_objects mm/slub.c:2632 [inline]
 ___slab_alloc+0x2a6/0x450 mm/slub.c:2796
 __slab_alloc+0x63/0xa0 mm/slub.c:2836
 slab_alloc_node mm/slub.c:2918 [inline]
 slab_alloc mm/slub.c:2960 [inline]
 __kmalloc_track_caller+0x1ef/0x320 mm/slub.c:4541
 __kmalloc_reserve net/core/skbuff.c:144 [inline]
 __alloc_skb+0xdc/0x520 net/core/skbuff.c:212
 alloc_skb include/linux/skbuff.h:1126 [inline]
 alloc_skb_with_frags+0xa2/0x560 net/core/skbuff.c:5993
 sock_alloc_send_pskb+0x853/0x980 net/core/sock.c:2393
 unix_dgram_sendmsg+0x5f4/0x17d0 net/unix/af_unix.c:1725
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 sock_write_iter+0x29c/0x380 net/socket.c:1018
 call_write_iter include/linux/fs.h:2066 [inline]
 new_sync_write fs/read_write.c:518 [inline]
 vfs_write+0x725/0xd60 fs/read_write.c:605
 ksys_write+0x140/0x240 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+0x31/0x40 arch/x86/entry/common.c:46
page_owner free stack trace missing

Memory state around the buggy address:
 ffff8881104aff00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff8881104aff80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff8881104b0000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff8881104b0080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8881104b0100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================