================================================================== BUG: KASAN: use-after-free in ext4_xattr_delete_inode+0xcd0/0xce0 fs/ext4/xattr.c:2911 Read of size 4 at addr ffff88812b65a000 by task syz-executor/465 CPU: 1 PID: 465 Comm: syz-executor Not tainted 5.15.176-syzkaller-1078825-gd1a25a6a4b3b #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x151/0x1c0 lib/dump_stack.c:106 print_address_description+0x87/0x3b0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:427 [inline] kasan_report+0x179/0x1c0 mm/kasan/report.c:444 __asan_report_load4_noabort+0x14/0x20 mm/kasan/report_generic.c:308 ext4_xattr_delete_inode+0xcd0/0xce0 fs/ext4/xattr.c:2911 ext4_evict_inode+0xea1/0x14e0 fs/ext4/inode.c:300 evict+0x529/0x930 fs/inode.c:622 iput_final fs/inode.c:1744 [inline] iput+0x63b/0x7e0 fs/inode.c:1770 d_delete_notify include/linux/fsnotify.h:278 [inline] vfs_rmdir+0x359/0x470 fs/namei.c:4162 do_rmdir+0x3ab/0x630 fs/namei.c:4210 __do_sys_unlinkat fs/namei.c:4390 [inline] __se_sys_unlinkat fs/namei.c:4384 [inline] __x64_sys_unlinkat+0xdf/0xf0 fs/namei.c:4384 x64_sys_call+0x6e9/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:264 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f23f9524cf7 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:00007ffc178f4a98 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f23f9524cf7 RDX: 0000000000000200 RSI: 00007ffc178f5c40 RDI: 00000000ffffff9c RBP: 00007f23f95981cc R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000207 R12: 00007ffc178f5c40 R13: 00007f23f95981cc R14: 000000000000cdeb R15: 00007ffc178f7df0 Allocated by task 417: 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+0xb1/0xe0 mm/kasan/common.c:466 kasan_slab_alloc include/linux/kasan.h:217 [inline] slab_post_alloc_hook+0x53/0x2c0 mm/slab.h:550 slab_alloc_node mm/slub.c:3240 [inline] slab_alloc mm/slub.c:3250 [inline] kmem_cache_alloc+0xf5/0x250 mm/slub.c:3255 skb_clone+0x1d1/0x360 net/core/skbuff.c:1547 do_one_broadcast net/netlink/af_netlink.c:1448 [inline] netlink_broadcast_filtered+0x692/0x1220 net/netlink/af_netlink.c:1523 netlink_broadcast net/netlink/af_netlink.c:1547 [inline] netlink_sendmsg+0x990/0xd20 net/netlink/af_netlink.c:1907 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2436 ___sys_sendmsg+0x252/0x2e0 net/socket.c:2490 __sys_sendmsg net/socket.c:2519 [inline] __do_sys_sendmsg net/socket.c:2528 [inline] __se_sys_sendmsg+0x19a/0x260 net/socket.c:2526 __x64_sys_sendmsg+0x7b/0x90 net/socket.c:2526 x64_sys_call+0x16a/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 417: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:45 kasan_set_free_info+0x23/0x40 mm/kasan/generic.c:370 ____kasan_slab_free+0x126/0x160 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:1723 [inline] slab_free_freelist_hook+0xbd/0x190 mm/slub.c:1749 slab_free mm/slub.c:3521 [inline] kmem_cache_free+0x115/0x330 mm/slub.c:3539 kfree_skbmem+0x104/0x170 __kfree_skb net/core/skbuff.c:758 [inline] kfree_skb_reason net/core/skbuff.c:778 [inline] kfree_skb+0xc2/0x360 net/core/skbuff.c:792 netlink_broadcast_filtered+0x717/0x1220 net/netlink/af_netlink.c:1523 netlink_broadcast net/netlink/af_netlink.c:1547 [inline] netlink_sendmsg+0x990/0xd20 net/netlink/af_netlink.c:1907 sock_sendmsg_nosec net/socket.c:704 [inline] __sock_sendmsg net/socket.c:716 [inline] ____sys_sendmsg+0x59e/0x8f0 net/socket.c:2436 ___sys_sendmsg+0x252/0x2e0 net/socket.c:2490 __sys_sendmsg net/socket.c:2519 [inline] __do_sys_sendmsg net/socket.c:2528 [inline] __se_sys_sendmsg+0x19a/0x260 net/socket.c:2526 __x64_sys_sendmsg+0x7b/0x90 net/socket.c:2526 x64_sys_call+0x16a/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:47 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 The buggy address belongs to the object at ffff88812b65a000 which belongs to the cache skbuff_head_cache of size 248 The buggy address is located 0 bytes inside of 248-byte region [ffff88812b65a000, ffff88812b65a0f8) The buggy address belongs to the page: page:ffffea0004ad9680 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x12b65a flags: 0x4000000000000200(slab|zone=1) raw: 4000000000000200 0000000000000000 dead000000000122 ffff8881081aa780 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 8, ts 52768891095, free_ts 52740119693 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1a3/0x1b0 mm/page_alloc.c:2605 prep_new_page+0x1b/0x110 mm/page_alloc.c:2611 get_page_from_freelist+0x3550/0x35d0 mm/page_alloc.c:4485 __alloc_pages+0x27e/0x8f0 mm/page_alloc.c:5780 allocate_slab mm/slub.c:1932 [inline] new_slab+0x9a/0x4e0 mm/slub.c:1995 ___slab_alloc+0x39e/0x830 mm/slub.c:3028 __slab_alloc+0x4a/0x90 mm/slub.c:3115 slab_alloc_node mm/slub.c:3206 [inline] slab_alloc mm/slub.c:3250 [inline] kmem_cache_alloc+0x139/0x250 mm/slub.c:3255 kmem_cache_alloc_node include/linux/slab.h:474 [inline] __alloc_skb+0xbe/0x550 net/core/skbuff.c:416 alloc_skb include/linux/skbuff.h:1183 [inline] nlmsg_new include/net/netlink.h:953 [inline] rtmsg_ifinfo_build_skb+0x7f/0x180 net/core/rtnetlink.c:3881 unregister_netdevice_many+0xea2/0x17c0 net/core/dev.c:11122 ip6_tnl_exit_batch_net+0x3c4/0x410 net/ipv6/ip6_tunnel.c:2309 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x6ce/0xc00 net/core/net_namespace.c:599 process_one_work+0x6bb/0xc10 kernel/workqueue.c:2325 worker_thread+0xad5/0x12a0 kernel/workqueue.c:2472 kthread+0x421/0x510 kernel/kthread.c:337 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+0x7c8/0x7d0 mm/page_alloc.c:3534 free_unref_page_list+0x14b/0xa60 mm/page_alloc.c:3671 release_pages+0x1310/0x1370 mm/swap.c:1009 free_pages_and_swap_cache+0x8a/0xa0 mm/swap_state.c:320 tlb_batch_pages_flush mm/mmu_gather.c:49 [inline] tlb_flush_mmu_free mm/mmu_gather.c:240 [inline] tlb_flush_mmu mm/mmu_gather.c:247 [inline] tlb_finish_mmu+0x177/0x320 mm/mmu_gather.c:338 unmap_region+0x304/0x350 mm/mmap.c:2680 __do_munmap+0x13e4/0x19d0 mm/mmap.c:2913 __vm_munmap+0x166/0x2a0 mm/mmap.c:2966 __do_sys_munmap mm/mmap.c:2992 [inline] __se_sys_munmap mm/mmap.c:2988 [inline] __x64_sys_munmap+0x6b/0x80 mm/mmap.c:2988 x64_sys_call+0x75/0x9a0 arch/x86/include/generated/asm/syscalls_64.h:12 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Memory state around the buggy address: ffff88812b659f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88812b659f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88812b65a000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88812b65a080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc ffff88812b65a100: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ==================================================================