================================================================== BUG: KASAN: slab-use-after-free in skb_release_head_state+0xba/0x250 net/core/skbuff.c:1125 Read of size 8 at addr ffff888064fcca60 by task syz-executor.1/12033 CPU: 0 PID: 12033 Comm: syz-executor.1 Not tainted 6.9.0-rc5-syzkaller-01160-g2bd87951de65 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:114 print_address_description mm/kasan/report.c:377 [inline] print_report+0x169/0x550 mm/kasan/report.c:488 kasan_report+0x143/0x180 mm/kasan/report.c:601 skb_release_head_state+0xba/0x250 net/core/skbuff.c:1125 skb_release_all net/core/skbuff.c:1138 [inline] __kfree_skb net/core/skbuff.c:1154 [inline] kfree_skb_reason+0x16d/0x3b0 net/core/skbuff.c:1190 kfree_skb include/linux/skbuff.h:1268 [inline] __hci_req_sync+0x62f/0x950 net/bluetooth/hci_request.c:184 hci_req_sync+0xa9/0xd0 net/bluetooth/hci_request.c:206 hci_dev_cmd+0x518/0xa90 net/bluetooth/hci_core.c:790 sock_do_ioctl+0x158/0x460 net/socket.c:1222 sock_ioctl+0x629/0x8e0 net/socket.c:1341 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:904 [inline] __se_sys_ioctl+0xfc/0x170 fs/ioctl.c:890 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f1ac2c7dc0b Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00 RSP: 002b:00007ffd1f11dcb0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f1ac2c7dc0b RDX: 00007ffd1f11dd28 RSI: 00000000400448dd RDI: 0000000000000003 RBP: 000055556b8e6430 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000001 R13: 0000000000000001 R14: 00007f1ac2dac9d8 R15: 000000000000000c Allocated by task 9039: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 unpoison_slab_object mm/kasan/common.c:312 [inline] __kasan_slab_alloc+0x66/0x80 mm/kasan/common.c:338 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook mm/slub.c:3798 [inline] slab_alloc_node mm/slub.c:3845 [inline] kmem_cache_alloc+0x174/0x340 mm/slub.c:3852 skb_clone+0x20c/0x390 net/core/skbuff.c:2019 hci_send_cmd_sync net/bluetooth/hci_core.c:4220 [inline] hci_cmd_work+0x29e/0x670 net/bluetooth/hci_core.c:4240 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Freed by task 9039: kasan_save_stack mm/kasan/common.c:47 [inline] kasan_save_track+0x3f/0x80 mm/kasan/common.c:68 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:579 poison_slab_object+0xa6/0xe0 mm/kasan/common.c:240 __kasan_slab_free+0x37/0x60 mm/kasan/common.c:256 kasan_slab_free include/linux/kasan.h:184 [inline] slab_free_hook mm/slub.c:2106 [inline] slab_free mm/slub.c:4280 [inline] kmem_cache_free+0x10b/0x2c0 mm/slub.c:4344 kfree_skb include/linux/skbuff.h:1268 [inline] hci_req_sync_complete+0xe7/0x290 net/bluetooth/hci_request.c:109 hci_event_packet+0xc71/0x1540 net/bluetooth/hci_event.c:7607 hci_rx_work+0x3e8/0xca0 net/bluetooth/hci_core.c:4171 process_one_work kernel/workqueue.c:3254 [inline] process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3335 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416 kthread+0x2f0/0x390 kernel/kthread.c:388 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 The buggy address belongs to the object at ffff888064fcca00 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 96 bytes inside of freed 240-byte region [ffff888064fcca00, ffff888064fccaf0) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x64fcc flags: 0xfff80000000800(slab|node=0|zone=1|lastcpupid=0xfff) page_type: 0xffffffff() raw: 00fff80000000800 ffff888018e97780 dead000000000100 dead000000000122 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 4527, tgid 113248136 (klogd), ts 4527, free_ts 488105652744 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1ea/0x210 mm/page_alloc.c:1534 prep_new_page mm/page_alloc.c:1541 [inline] get_page_from_freelist+0x3410/0x35b0 mm/page_alloc.c:3317 __alloc_pages+0x256/0x6c0 mm/page_alloc.c:4575 __alloc_pages_node include/linux/gfp.h:238 [inline] alloc_pages_node include/linux/gfp.h:261 [inline] alloc_slab_page+0x5f/0x160 mm/slub.c:2175 allocate_slab mm/slub.c:2338 [inline] new_slab+0x84/0x2f0 mm/slub.c:2391 ___slab_alloc+0xc73/0x1260 mm/slub.c:3525 __slab_alloc mm/slub.c:3610 [inline] __slab_alloc_node mm/slub.c:3663 [inline] slab_alloc_node mm/slub.c:3835 [inline] kmem_cache_alloc_node+0x24a/0x380 mm/slub.c:3888 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:659 alloc_skb include/linux/skbuff.h:1319 [inline] alloc_skb_with_frags+0xc3/0x770 net/core/skbuff.c:6458 sock_alloc_send_pskb+0x91a/0xa60 net/core/sock.c:2794 unix_dgram_sendmsg+0x6d3/0x1f80 net/unix/af_unix.c:1973 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg+0x221/0x270 net/socket.c:745 __sys_sendto+0x3a4/0x4f0 net/socket.c:2191 __do_sys_sendto net/socket.c:2203 [inline] __se_sys_sendto net/socket.c:2199 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2199 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf5/0x240 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 10179 tgid 10179 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1141 [inline] free_unref_page_prepare+0x986/0xab0 mm/page_alloc.c:2347 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2487 vfree+0x186/0x2e0 mm/vmalloc.c:3340 kcov_put kernel/kcov.c:429 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:525 __fput+0x429/0x8a0 fs/file_table.c:422 task_work_run+0x24f/0x310 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa1b/0x27e0 kernel/exit.c:878 do_group_exit+0x207/0x2c0 kernel/exit.c:1027 get_signal+0x16a1/0x1740 kernel/signal.c:2911 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:310 exit_to_user_mode_loop kernel/entry/common.c:111 [inline] exit_to_user_mode_prepare include/linux/entry-common.h:328 [inline] __syscall_exit_to_user_mode_work kernel/entry/common.c:207 [inline] syscall_exit_to_user_mode+0xc9/0x370 kernel/entry/common.c:218 do_syscall_64+0x102/0x240 arch/x86/entry/common.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888064fcc900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888064fcc980: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc >ffff888064fcca00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888064fcca80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff888064fccb00: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ==================================================================