EXT4-fs (loop6): mounted filesystem without journal. Opts: block_validity,bsddf,nombcache,inode_readahead_blks=0x0000000000000000,debug_want_extra_isize=0x0000000000000080,orlov,nogrpid,noauto_da_alloc,grpjquota=,,errors=continue
EXT4-fs error (device loop6): xattr_find_entry:297: inode #12: comm syz.6.121: corrupted xattr entries
==================================================================
BUG: KASAN: use-after-free in xattr_find_entry fs/ext4/xattr.c:294 [inline]
BUG: KASAN: use-after-free in ext4_xattr_ibody_get+0x62e/0x690 fs/ext4/xattr.c:601
Read of size 4 at addr ffff888123097004 by task syz.6.121/831

CPU: 0 PID: 831 Comm: syz.6.121 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026
Call Trace:
 __dump_stack+0x21/0x24 lib/dump_stack.c:77
 dump_stack_lvl+0x1a7/0x208 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
 xattr_find_entry fs/ext4/xattr.c:294 [inline]
 ext4_xattr_ibody_get+0x62e/0x690 fs/ext4/xattr.c:601
 ext4_xattr_get+0x116/0x820 fs/ext4/xattr.c:655
 ext4_get_acl+0x6c/0x660 fs/ext4/acl.c:162
 get_acl+0x15f/0x270 fs/posix_acl.c:141
 posix_acl_chmod+0xe4/0x240 fs/posix_acl.c:565
 ext4_setattr+0x9fa/0x1760 fs/ext4/inode.c:5722
 notify_change+0xab3/0xe40 fs/attr.c:410
 chmod_common+0x1e1/0x390 fs/open.c:584
 do_fchmodat+0xd4/0x1a0 fs/open.c:622
 __do_sys_fchmodat fs/open.c:635 [inline]
 __se_sys_fchmodat fs/open.c:632 [inline]
 __x64_sys_fchmodat+0x7b/0x90 fs/open.c:632
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb
RIP: 0033:0x7fec1519b629
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fec13bf6028 EFLAGS: 00000246 ORIG_RAX: 000000000000010c
RAX: ffffffffffffffda RBX: 00007fec15414fa0 RCX: 00007fec1519b629
RDX: 000000000000017f RSI: 0000200000000300 RDI: ffffffffffffff9c
RBP: 00007fec15231b39 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fec15415038 R14: 00007fec15414fa0 R15: 00007ffc458896f8

Allocated by task 703:
 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+0xbd/0xf0 mm/kasan/common.c:463
 kasan_slab_alloc include/linux/kasan.h:244 [inline]
 slab_post_alloc_hook+0x5d/0x2f0 mm/slab.h:580
 slab_alloc_node mm/slub.c:2952 [inline]
 slab_alloc mm/slub.c:2960 [inline]
 kmem_cache_alloc+0x162/0x2d0 mm/slub.c:2965
 kmem_cache_alloc_node include/linux/slab.h:426 [inline]
 __alloc_skb+0x9e/0x520 net/core/skbuff.c:200
 alloc_skb include/linux/skbuff.h:1126 [inline]
 nlmsg_new include/net/netlink.h:953 [inline]
 rtmsg_fib+0x60a/0xd90 net/ipv4/fib_semantics.c:522
 fib_table_insert+0xf48/0x1d70 net/ipv4/fib_trie.c:1335
 fib_magic net/ipv4/fib_frontend.c:1107 [inline]
 fib_add_ifaddr+0x8a3/0xfc0 net/ipv4/fib_frontend.c:1144
 fib_netdev_event+0x231/0x5d0 net/ipv4/fib_frontend.c:1491
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0x90/0x100 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_notify_flags+0x2c1/0x560 net/core/dev.c:8572
 dev_change_flags+0xe8/0x1a0 net/core/dev.c:8610
 do_setlink+0xc06/0x3e10 net/core/rtnetlink.c:2732
 __rtnl_newlink net/core/rtnetlink.c:3410 [inline]
 rtnl_newlink+0x1534/0x18f0 net/core/rtnetlink.c:3530
 rtnetlink_rcv_msg+0xa31/0xcc0 net/core/rtnetlink.c:5610
 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2503
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5628
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x89c/0xb50 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 __sys_sendto+0x467/0x620 net/socket.c:2006
 __do_sys_sendto net/socket.c:2018 [inline]
 __se_sys_sendto net/socket.c:2014 [inline]
 __x64_sys_sendto+0xe5/0x100 net/socket.c:2014
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

Freed by task 703:
 kasan_save_stack mm/kasan/common.c:38 [inline]
 kasan_set_track+0x4a/0x70 mm/kasan/common.c:45
 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370
 ____kasan_slab_free+0x125/0x160 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:1600 [inline]
 slab_free_freelist_hook+0xc5/0x190 mm/slub.c:1626
 slab_free mm/slub.c:3208 [inline]
 kmem_cache_free+0x100/0x2d0 mm/slub.c:3224
 kfree_skbmem+0x10c/0x180 net/core/skbuff.c:-1
 __kfree_skb net/core/skbuff.c:695 [inline]
 consume_skb+0xb3/0x1f0 net/core/skbuff.c:851
 netlink_broadcast_filtered+0x117d/0x1270 net/netlink/af_netlink.c:1530
 netlink_broadcast net/netlink/af_netlink.c:1552 [inline]
 nlmsg_multicast include/net/netlink.h:1033 [inline]
 nlmsg_notify+0xed/0x1b0 net/netlink/af_netlink.c:2546
 rtnl_notify+0x9a/0xc0 net/core/rtnetlink.c:737
 rtmsg_fib+0x78d/0xd90 net/ipv4/fib_semantics.c:541
 fib_table_insert+0xf48/0x1d70 net/ipv4/fib_trie.c:1335
 fib_magic net/ipv4/fib_frontend.c:1107 [inline]
 fib_add_ifaddr+0x8a3/0xfc0 net/ipv4/fib_frontend.c:1144
 fib_netdev_event+0x231/0x5d0 net/ipv4/fib_frontend.c:1491
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0x90/0x100 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_notify_flags+0x2c1/0x560 net/core/dev.c:8572
 dev_change_flags+0xe8/0x1a0 net/core/dev.c:8610
 do_setlink+0xc06/0x3e10 net/core/rtnetlink.c:2732
 __rtnl_newlink net/core/rtnetlink.c:3410 [inline]
 rtnl_newlink+0x1534/0x18f0 net/core/rtnetlink.c:3530
 rtnetlink_rcv_msg+0xa31/0xcc0 net/core/rtnetlink.c:5610
 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2503
 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5628
 netlink_unicast_kernel net/netlink/af_netlink.c:1314 [inline]
 netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1340
 netlink_sendmsg+0x89c/0xb50 net/netlink/af_netlink.c:1914
 sock_sendmsg_nosec net/socket.c:652 [inline]
 __sock_sendmsg net/socket.c:664 [inline]
 __sys_sendto+0x467/0x620 net/socket.c:2006
 __do_sys_sendto net/socket.c:2018 [inline]
 __se_sys_sendto net/socket.c:2014 [inline]
 __x64_sys_sendto+0xe5/0x100 net/socket.c:2014
 do_syscall_64+0x31/0x40 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x61/0xcb

The buggy address belongs to the object at ffff888123097000
 which belongs to the cache skbuff_head_cache of size 248
The buggy address is located 4 bytes inside of
 248-byte region [ffff888123097000, ffff8881230970f8)
The buggy address belongs to the page:
page:ffffea00048c25c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x123097
flags: 0x4000000000000200(slab)
raw: 4000000000000200 dead000000000100 dead000000000122 ffff888107d93800
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 703, ts 43442441728, free_ts 43436525862
 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+0x223b/0x23d0 mm/page_alloc.c:4254
 __alloc_pages_nodemask+0x290/0x620 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]
 kmem_cache_alloc+0x1ac/0x2d0 mm/slub.c:2965
 kmem_cache_alloc_node include/linux/slab.h:426 [inline]
 __alloc_skb+0x9e/0x520 net/core/skbuff.c:200
 alloc_skb include/linux/skbuff.h:1126 [inline]
 nlmsg_new include/net/netlink.h:953 [inline]
 rtmsg_fib+0x60a/0xd90 net/ipv4/fib_semantics.c:522
 fib_table_insert+0xf48/0x1d70 net/ipv4/fib_trie.c:1335
 fib_magic net/ipv4/fib_frontend.c:1107 [inline]
 fib_add_ifaddr+0x8a3/0xfc0 net/ipv4/fib_frontend.c:1144
 fib_netdev_event+0x231/0x5d0 net/ipv4/fib_frontend.c:1491
 notifier_call_chain kernel/notifier.c:83 [inline]
 raw_notifier_call_chain+0x90/0x100 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_notify_flags+0x2c1/0x560 net/core/dev.c:8572
 dev_change_flags+0xe8/0x1a0 net/core/dev.c:8610
 do_setlink+0xc06/0x3e10 net/core/rtnetlink.c:2732
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+0x2b7/0x2d0 mm/page_alloc.c:3336
 free_unref_page mm/page_alloc.c:3391 [inline]
 free_the_page mm/page_alloc.c:5429 [inline]
 __free_pages+0x146/0x3b0 mm/page_alloc.c:5440
 __vunmap+0x86d/0x9f0 mm/vmalloc.c:2307
 free_work+0x5a/0x80 mm/vmalloc.c:69
 process_one_work+0x6e1/0xba0 kernel/workqueue.c:2301
 worker_thread+0xa6a/0x13c0 kernel/workqueue.c:2447
 kthread+0x346/0x3d0 kernel/kthread.c:313
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:298

Memory state around the buggy address:
 ffff888123096f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffff888123096f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffff888123097000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                   ^
 ffff888123097080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc
 ffff888123097100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb
==================================================================
EXT4-fs error (device loop6): xattr_find_entry:297: inode #12: comm syz.6.121: corrupted xattr entries