EXT4-fs (loop5): mounted filesystem without journal. Opts: ,errors=continue. Quota mode: none. ================================================================== BUG: KASAN: use-after-free in ext4_xattr_rehash fs/ext4/xattr.c:3135 [inline] BUG: KASAN: use-after-free in ext4_xattr_set_entry+0xe1f/0x3940 fs/ext4/xattr.c:1820 Read of size 4 at addr ffff88813056b004 by task syz.5.17/430 CPU: 1 PID: 430 Comm: syz.5.17 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: __dump_stack+0x21/0x30 lib/dump_stack.c:88 dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106 print_address_description+0x7f/0x2c0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0xf1/0x140 mm/kasan/report.c:444 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 ext4_xattr_rehash fs/ext4/xattr.c:3135 [inline] ext4_xattr_set_entry+0xe1f/0x3940 fs/ext4/xattr.c:1820 ext4_xattr_block_set+0x4f8/0x2d10 fs/ext4/xattr.c:1924 ext4_xattr_set_handle+0xbc4/0x12b0 fs/ext4/xattr.c:2407 ext4_xattr_set+0x242/0x320 fs/ext4/xattr.c:2508 ext4_xattr_trusted_set+0x3c/0x50 fs/ext4/xattr_trusted.c:38 __vfs_setxattr+0x3e1/0x430 fs/xattr.c:182 __vfs_setxattr_noperm+0x12a/0x5e0 fs/xattr.c:216 __vfs_setxattr_locked+0x212/0x230 fs/xattr.c:277 vfs_setxattr+0x167/0x2e0 fs/xattr.c:303 do_setxattr fs/xattr.c:588 [inline] setxattr+0x36c/0x390 fs/xattr.c:611 path_setxattr+0x147/0x290 fs/xattr.c:630 __do_sys_lsetxattr fs/xattr.c:653 [inline] __se_sys_lsetxattr fs/xattr.c:649 [inline] __x64_sys_lsetxattr+0xc2/0xe0 fs/xattr.c:649 x64_sys_call+0x8cc/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:190 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7fb265b80629 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:00007ffcb3b77878 EFLAGS: 00000246 ORIG_RAX: 00000000000000bd RAX: ffffffffffffffda RBX: 00007fb265df9fa0 RCX: 00007fb265b80629 RDX: 0000200000000480 RSI: 00002000000000c0 RDI: 0000200000000100 RBP: 00007fb265c16b39 R08: 0000000000000000 R09: 0000000000000000 R10: 000000000000fe37 R11: 0000000000000246 R12: 0000000000000000 R13: 00007fb265df9fac R14: 00007fb265df9fa0 R15: 00007fb265df9fa0 Allocated by task 368: 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:433 [inline] __kasan_slab_alloc+0xbd/0xf0 mm/kasan/common.c:466 kasan_slab_alloc include/linux/kasan.h:217 [inline] slab_post_alloc_hook+0x4f/0x2b0 mm/slab.h:550 slab_alloc_node mm/slub.c:3245 [inline] slab_alloc mm/slub.c:3255 [inline] kmem_cache_alloc+0xf7/0x260 mm/slub.c:3260 kmem_cache_alloc_node include/linux/slab.h:492 [inline] __alloc_skb+0xe0/0x740 net/core/skbuff.c:416 alloc_skb include/linux/skbuff.h:1183 [inline] nlmsg_new include/net/netlink.h:953 [inline] inet6_ifa_notify net/ipv6/addrconf.c:5540 [inline] __ipv6_ifa_notify+0x200/0xe70 net/ipv6/addrconf.c:6195 ipv6_ifa_notify net/ipv6/addrconf.c:6247 [inline] inet6_addr_add+0x671/0xa10 net/ipv6/addrconf.c:3034 inet6_rtm_newaddr+0x6e7/0x9c0 net/ipv6/addrconf.c:4975 rtnetlink_rcv_msg+0xa4b/0xce0 net/core/rtnetlink.c:5650 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2511 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5668 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x879/0xb80 net/netlink/af_netlink.c:1922 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x46d/0x620 net/socket.c:2062 __do_sys_sendto net/socket.c:2074 [inline] __se_sys_sendto net/socket.c:2070 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2070 x64_sys_call+0x178/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 368: 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:365 __kasan_slab_free+0x11/0x20 mm/kasan/common.c:373 kasan_slab_free include/linux/kasan.h:193 [inline] slab_free_hook mm/slub.c:1728 [inline] slab_free_freelist_hook+0xc2/0x190 mm/slub.c:1754 slab_free mm/slub.c:3526 [inline] kmem_cache_free+0x100/0x320 mm/slub.c:3544 kfree_skbmem+0x10c/0x180 net/core/skbuff.c:-1 __kfree_skb net/core/skbuff.c:758 [inline] consume_skb+0xb3/0x1f0 net/core/skbuff.c:930 netlink_broadcast_filtered+0x113a/0x1230 net/netlink/af_netlink.c:1538 netlink_broadcast net/netlink/af_netlink.c:1560 [inline] nlmsg_multicast include/net/netlink.h:1033 [inline] nlmsg_notify+0xed/0x1b0 net/netlink/af_netlink.c:2554 rtnl_notify+0x9a/0xc0 net/core/rtnetlink.c:759 inet6_ifa_notify net/ipv6/addrconf.c:5551 [inline] __ipv6_ifa_notify+0x24b/0xe70 net/ipv6/addrconf.c:6195 ipv6_ifa_notify net/ipv6/addrconf.c:6247 [inline] inet6_addr_add+0x671/0xa10 net/ipv6/addrconf.c:3034 inet6_rtm_newaddr+0x6e7/0x9c0 net/ipv6/addrconf.c:4975 rtnetlink_rcv_msg+0xa4b/0xce0 net/core/rtnetlink.c:5650 netlink_rcv_skb+0x1f5/0x440 net/netlink/af_netlink.c:2511 rtnetlink_rcv+0x1c/0x20 net/core/rtnetlink.c:5668 netlink_unicast_kernel net/netlink/af_netlink.c:1322 [inline] netlink_unicast+0x876/0xa40 net/netlink/af_netlink.c:1348 netlink_sendmsg+0x879/0xb80 net/netlink/af_netlink.c:1922 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] __sys_sendto+0x46d/0x620 net/socket.c:2062 __do_sys_sendto net/socket.c:2074 [inline] __se_sys_sendto net/socket.c:2070 [inline] __x64_sys_sendto+0xe5/0x100 net/socket.c:2070 x64_sys_call+0x178/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:45 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88813056b000 which belongs to the cache skbuff_head_cache of size 248 The buggy address is located 4 bytes inside of 248-byte region [ffff88813056b000, ffff88813056b0f8) The buggy address belongs to the page: page:ffffea0004c15ac0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x13056b flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 0000000000000000 dead000000000122 ffff8881081aa000 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 373, ts 29406716502, free_ts 29406287396 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x192/0x1b0 mm/page_alloc.c:2605 prep_new_page+0x1c/0x110 mm/page_alloc.c:2611 get_page_from_freelist+0x2d3a/0x2dc0 mm/page_alloc.c:4485 __alloc_pages+0x1a2/0x460 mm/page_alloc.c:5808 alloc_slab_page mm/slub.c:-1 [inline] allocate_slab mm/slub.c:1937 [inline] new_slab+0xa1/0x4d0 mm/slub.c:2000 ___slab_alloc+0x381/0x810 mm/slub.c:3033 __slab_alloc+0x49/0x90 mm/slub.c:3120 slab_alloc_node mm/slub.c:3211 [inline] slab_alloc mm/slub.c:3255 [inline] kmem_cache_alloc+0x138/0x260 mm/slub.c:3260 kmem_cache_alloc_node include/linux/slab.h:492 [inline] __alloc_skb+0xe0/0x740 net/core/skbuff.c:416 alloc_skb include/linux/skbuff.h:1183 [inline] nlmsg_new include/net/netlink.h:953 [inline] rtmsg_fib+0x60a/0xe20 net/ipv4/fib_semantics.c:520 fib_table_insert+0xbe4/0x1ea0 net/ipv4/fib_trie.c:1379 fib_magic net/ipv4/fib_frontend.c:1107 [inline] fib_add_ifaddr+0xb4d/0xf10 net/ipv4/fib_frontend.c:1151 fib_netdev_event+0x231/0x5d0 net/ipv4/fib_frontend.c:1489 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0x90/0x100 kernel/notifier.c:391 call_netdevice_notifiers_info net/core/dev.c:2070 [inline] call_netdevice_notifiers_extack net/core/dev.c:2082 [inline] call_netdevice_notifiers net/core/dev.c:2096 [inline] __dev_notify_flags+0x2c1/0x560 net/core/dev.c:8912 dev_change_flags+0xe8/0x1a0 net/core/dev.c:8950 page last free stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] free_pages_prepare mm/page_alloc.c:1472 [inline] free_pcp_prepare mm/page_alloc.c:1544 [inline] free_unref_page_prepare+0x542/0x550 mm/page_alloc.c:3534 free_unref_page_list+0x13a/0x9d0 mm/page_alloc.c:3671 release_pages+0x1006/0x1060 mm/swap.c:1015 __pagevec_release+0x71/0xe0 mm/swap.c:1035 pagevec_release include/linux/pagevec.h:81 [inline] truncate_inode_pages_range+0x34c/0xe00 mm/truncate.c:332 truncate_inode_pages mm/truncate.c:428 [inline] truncate_inode_pages_final+0x82/0x90 mm/truncate.c:467 ext4_evict_inode+0x655/0x1460 fs/ext4/inode.c:214 evict+0x4c9/0x8d0 fs/inode.c:650 iput_final fs/inode.c:1779 [inline] iput+0x635/0x7c0 fs/inode.c:1805 ext4_mb_release+0x786/0xd20 fs/ext4/mballoc.c:3654 ext4_put_super+0x1eb/0xa70 fs/ext4/super.c:1204 generic_shutdown_super+0x151/0x330 fs/super.c:475 kill_block_super+0x7f/0xf0 fs/super.c:1427 deactivate_locked_super+0xa0/0x100 fs/super.c:335 deactivate_super+0xaf/0xe0 fs/super.c:366 cleanup_mnt+0x45b/0x510 fs/namespace.c:1148 Memory state around the buggy address: ffff88813056af00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88813056af80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88813056b000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88813056b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc ffff88813056b100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ==================================================================