================================================================== BUG: KASAN: slab-use-after-free in skb_dst_drop include/net/dst.h:281 [inline] BUG: KASAN: slab-use-after-free in skb_release_head_state+0x3b/0x240 net/core/skbuff.c:1040 Read of size 8 at addr ffff88806c0a2a58 by task syz.0.9734/28290 CPU: 1 PID: 28290 Comm: syz.0.9734 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 skb_dst_drop include/net/dst.h:281 [inline] skb_release_head_state+0x3b/0x240 net/core/skbuff.c:1040 skb_release_all net/core/skbuff.c:1055 [inline] __kfree_skb net/core/skbuff.c:1071 [inline] kfree_skb_reason+0xd7/0x170 net/core/skbuff.c:1107 kfree_skb include/linux/skbuff.h:1264 [inline] __hci_req_sync+0x613/0x910 net/bluetooth/hci_request.c:184 hci_req_sync+0xa2/0xc0 net/bluetooth/hci_request.c:206 hci_inquiry+0x38f/0x600 net/bluetooth/hci_core.c:394 sock_do_ioctl+0xfc/0x310 net/socket.c:1219 sock_ioctl+0x5ba/0x7e0 net/socket.c:1340 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:871 [inline] __se_sys_ioctl+0xfd/0x170 fs/ioctl.c:857 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f19e179c799 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:00007f19e2607028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f19e1a15fa0 RCX: 00007f19e179c799 RDX: 0000200000000280 RSI: 00000000800448f0 RDI: 0000000000000004 RBP: 00007f19e1832c99 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f19e1a16038 R14: 00007f19e1a15fa0 R15: 00007ffeb126fee8 Allocated by task 5086: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x11a/0x2d0 mm/slub.c:3519 skb_clone+0x1eb/0x370 net/core/skbuff.c:1915 hci_send_cmd_sync net/bluetooth/hci_core.c:4067 [inline] hci_cmd_work+0x283/0x650 net/bluetooth/hci_core.c:4087 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Freed by task 5825: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] kmem_cache_free+0xf8/0x270 mm/slub.c:3852 kfree_skb include/linux/skbuff.h:1264 [inline] hci_send_cmd_sync net/bluetooth/hci_core.c:4066 [inline] hci_cmd_work+0x25d/0x650 net/bluetooth/hci_core.c:4087 process_one_work kernel/workqueue.c:2653 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2730 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2811 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88806c0a2a00 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 88 bytes inside of freed 240-byte region [ffff88806c0a2a00, ffff88806c0a2af0) The buggy address belongs to the physical page: page:ffffea0001b02880 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6c0a2 flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000800 ffff88801ea4f000 ffffea0001389280 dead000000000004 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 0x112820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 5820, tgid 5820 (syz-executor), ts 107191169305, free_ts 106668698962 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4500 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __kmem_cache_alloc_bulk mm/slub.c:3995 [inline] kmem_cache_alloc_bulk+0x1e6/0x5a0 mm/slub.c:4070 napi_skb_cache_get+0x11c/0x1e0 net/core/skbuff.c:333 __napi_build_skb net/core/skbuff.c:512 [inline] __napi_alloc_skb+0x230/0x560 net/core/skbuff.c:832 napi_alloc_skb include/linux/skbuff.h:3361 [inline] page_to_skb+0x2be/0x890 drivers/net/virtio_net.c:570 receive_mergeable drivers/net/virtio_net.c:1703 [inline] receive_buf+0x2fe/0x3820 drivers/net/virtio_net.c:1835 virtnet_receive drivers/net/virtio_net.c:2155 [inline] virtnet_poll+0x5dd/0x1280 drivers/net/virtio_net.c:2229 __napi_poll+0xc0/0x460 net/core/dev.c:6638 napi_poll net/core/dev.c:6705 [inline] net_rx_action+0x616/0xc40 net/core/dev.c:6841 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 __slab_free+0x35a/0x400 mm/slub.c:3736 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] __kmem_cache_alloc_node+0x13a/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x230 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] tomoyo_realpath_from_path+0xe3/0x5d0 security/tomoyo/realpath.c:251 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path2_perm+0x2e9/0x740 security/tomoyo/file.c:923 tomoyo_path_rename+0x14f/0x1a0 security/tomoyo/tomoyo.c:299 security_path_rename+0x16c/0x200 security/security.c:1829 do_renameat2+0x6be/0xce0 fs/namei.c:5020 __do_sys_rename fs/namei.c:5079 [inline] __se_sys_rename fs/namei.c:5077 [inline] __x64_sys_rename+0x86/0x90 fs/namei.c:5077 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 Memory state around the buggy address: ffff88806c0a2900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806c0a2980: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc >ffff88806c0a2a00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806c0a2a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff88806c0a2b00: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb 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