================================================================== BUG: KASAN: use-after-free in ext4_xattr_delete_inode+0xc1f/0xc30 fs/ext4/xattr.c:2917 Read of size 4 at addr ffff8881eb99b000 by task syz-executor/550 CPU: 1 PID: 550 Comm: syz-executor Not tainted 5.4.283-syzkaller-04981-g1cca65ac6abc #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/06/2024 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d8/0x241 lib/dump_stack.c:118 print_address_description+0x8c/0x600 mm/kasan/report.c:384 __kasan_report+0xf3/0x120 mm/kasan/report.c:516 kasan_report+0x30/0x60 mm/kasan/common.c:653 ext4_xattr_delete_inode+0xc1f/0xc30 fs/ext4/xattr.c:2917 ext4_evict_inode+0x1378/0x1ac0 fs/ext4/inode.c:318 evict+0x4ea/0x960 fs/inode.c:610 d_delete_notify include/linux/fsnotify.h:230 [inline] vfs_rmdir+0x24b/0x3c0 fs/namei.c:4040 do_rmdir+0x2c1/0x580 fs/namei.c:4088 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 RIP: 0033:0x7f5c1a9fc1a7 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:00007ffddf848e68 EFLAGS: 00000207 ORIG_RAX: 0000000000000107 RAX: ffffffffffffffda RBX: 0000000000000065 RCX: 00007f5c1a9fc1a7 RDX: 0000000000000200 RSI: 00007ffddf84a010 RDI: 00000000ffffff9c RBP: 00007f5c1aa6a64a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000100 R11: 0000000000000207 R12: 00007ffddf84a010 R13: 00007f5c1aa6a64a R14: 000000000000c25b R15: 00007ffddf84c1f0 Allocated by task 0: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] __kasan_kmalloc+0x171/0x210 mm/kasan/common.c:529 slab_post_alloc_hook mm/slab.h:584 [inline] slab_alloc_node mm/slub.c:2829 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc+0xd9/0x250 mm/slub.c:2842 dst_alloc+0x154/0x4c0 net/core/dst.c:93 ip6_dst_alloc net/ipv6/route.c:357 [inline] icmp6_dst_alloc+0xf1/0x550 net/ipv6/route.c:3186 mld_sendpack+0x4e2/0xb50 net/ipv6/mcast.c:1668 mld_send_cr net/ipv6/mcast.c:1975 [inline] mld_ifc_timer_expire+0x814/0xc10 net/ipv6/mcast.c:2474 call_timer_fn+0x36/0x390 kernel/time/timer.c:1448 expire_timers kernel/time/timer.c:1493 [inline] __run_timers+0x879/0xbe0 kernel/time/timer.c:1817 run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1830 __do_softirq+0x23b/0x6b7 kernel/softirq.c:292 Freed by task 0: save_stack mm/kasan/common.c:70 [inline] set_track mm/kasan/common.c:78 [inline] kasan_set_free_info mm/kasan/common.c:345 [inline] __kasan_slab_free+0x1b5/0x270 mm/kasan/common.c:487 slab_free_hook mm/slub.c:1455 [inline] slab_free_freelist_hook mm/slub.c:1494 [inline] slab_free mm/slub.c:3080 [inline] kmem_cache_free+0x10b/0x2c0 mm/slub.c:3096 dst_destroy+0x23f/0x320 net/core/dst.c:129 __rcu_reclaim kernel/rcu/rcu.h:222 [inline] rcu_do_batch+0x492/0xa00 kernel/rcu/tree.c:2167 rcu_core+0x4c8/0xcb0 kernel/rcu/tree.c:2387 __do_softirq+0x23b/0x6b7 kernel/softirq.c:292 The buggy address belongs to the object at ffff8881eb99b000 which belongs to the cache ip6_dst_cache of size 240 The buggy address is located 0 bytes inside of 240-byte region [ffff8881eb99b000, ffff8881eb99b0f0) The buggy address belongs to the page: page:ffffea0007ae66c0 refcount:1 mapcount:0 mapping:ffff8881ee583b80 index:0x0 flags: 0x8000000000000200(slab) raw: 8000000000000200 dead000000000100 dead000000000122 ffff8881ee583b80 raw: 0000000000000000 00000000800c000c 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 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL) set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook mm/page_alloc.c:2165 [inline] prep_new_page+0x18f/0x370 mm/page_alloc.c:2171 get_page_from_freelist+0x2d13/0x2d90 mm/page_alloc.c:3794 __alloc_pages_nodemask+0x393/0x840 mm/page_alloc.c:4893 alloc_slab_page+0x39/0x3c0 mm/slub.c:343 allocate_slab mm/slub.c:1683 [inline] new_slab+0x97/0x440 mm/slub.c:1749 new_slab_objects mm/slub.c:2505 [inline] ___slab_alloc+0x2fe/0x490 mm/slub.c:2667 __slab_alloc+0x62/0xa0 mm/slub.c:2707 slab_alloc_node mm/slub.c:2792 [inline] slab_alloc mm/slub.c:2837 [inline] kmem_cache_alloc+0x109/0x250 mm/slub.c:2842 dst_alloc+0x154/0x4c0 net/core/dst.c:93 ip6_dst_alloc net/ipv6/route.c:357 [inline] icmp6_dst_alloc+0xf1/0x550 net/ipv6/route.c:3186 ndisc_send_skb+0x262/0xc30 net/ipv6/ndisc.c:491 ndisc_send_ns+0x64d/0x830 net/ipv6/ndisc.c:653 addrconf_dad_work+0xb91/0x16f0 net/ipv6/addrconf.c:4196 process_one_work+0x765/0xd20 kernel/workqueue.c:2290 worker_thread+0xaef/0x1470 kernel/workqueue.c:2436 kthread+0x2da/0x360 kernel/kthread.c:288 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1176 [inline] free_pcp_prepare mm/page_alloc.c:1233 [inline] free_unref_page_prepare+0x297/0x380 mm/page_alloc.c:3085 free_unref_page mm/page_alloc.c:3134 [inline] free_the_page mm/page_alloc.c:4953 [inline] __free_pages mm/page_alloc.c:4961 [inline] free_pages+0x114/0x1b0 mm/page_alloc.c:4969 tlb_batch_list_free mm/mmu_gather.c:61 [inline] tlb_finish_mmu+0x249/0x320 mm/mmu_gather.c:280 unmap_region+0x31c/0x370 mm/mmap.c:2644 __do_munmap+0x649/0x850 mm/mmap.c:2875 __vm_munmap mm/mmap.c:2898 [inline] __do_sys_munmap mm/mmap.c:2924 [inline] __se_sys_munmap+0x11d/0x1a0 mm/mmap.c:2920 do_syscall_64+0xca/0x1c0 arch/x86/entry/common.c:290 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 Memory state around the buggy address: ffff8881eb99af00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff8881eb99af80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff8881eb99b000: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8881eb99b080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff8881eb99b100: fc fc fc fc fc fc fc fc fb fb fb fb fb fb fb fb ==================================================================