================================================================== BUG: KASAN: slab-use-after-free in skb_release_data+0x738/0x880 net/core/skbuff.c:1119 Read of size 1 at addr ffff88807d545a7e by task kworker/u9:1/4489 CPU: 0 PID: 4489 Comm: kworker/u9:1 Not tainted 6.10.0-rc4-syzkaller-00301-g5f583a3162ff #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 Workqueue: hci0 hci_rx_work 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_data+0x738/0x880 net/core/skbuff.c:1119 skb_release_all net/core/skbuff.c:1173 [inline] __kfree_skb net/core/skbuff.c:1187 [inline] kfree_skb_reason+0x1a3/0x3b0 net/core/skbuff.c:1223 kfree_skb include/linux/skbuff.h:1257 [inline] hci_req_sync_complete+0xe7/0x290 net/bluetooth/hci_request.c:109 hci_event_packet+0xc71/0x1540 net/bluetooth/hci_event.c:7479 hci_rx_work+0x3e8/0xca0 net/bluetooth/hci_core.c:4074 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393 kthread+0x2f0/0x390 kernel/kthread.c:389 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244 Allocated by task 4489: 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:3941 [inline] slab_alloc_node mm/slub.c:4001 [inline] kmem_cache_alloc_noprof+0x135/0x2a0 mm/slub.c:4008 skb_clone+0x20c/0x390 net/core/skbuff.c:2052 hci_send_cmd_sync net/bluetooth/hci_core.c:4123 [inline] hci_cmd_work+0x29e/0x670 net/bluetooth/hci_core.c:4143 process_one_work kernel/workqueue.c:3231 [inline] process_scheduled_works+0xa2c/0x1830 kernel/workqueue.c:3312 worker_thread+0x86d/0xd70 kernel/workqueue.c:3393 kthread+0x2f0/0x390 kernel/kthread.c:389 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 7350: 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+0xe0/0x150 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:2196 [inline] slab_free mm/slub.c:4437 [inline] kmem_cache_free+0x145/0x350 mm/slub.c:4512 kfree_skb include/linux/skbuff.h:1257 [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+0x4c5/0xa50 net/bluetooth/hci_core.c:787 compat_sock_ioctl+0x18b/0xf20 net/socket.c:3522 __do_compat_sys_ioctl fs/ioctl.c:1007 [inline] __se_compat_sys_ioctl+0x51c/0xca0 fs/ioctl.c:950 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e The buggy address belongs to the object at ffff88807d545a00 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 126 bytes inside of freed 240-byte region [ffff88807d545a00, ffff88807d545af0) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7d545 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffefff(slab) raw: 00fff00000000000 ffff888018ae0780 dead000000000122 0000000000000000 raw: 0000000000000000 00000000000c000c 00000001ffffefff 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 0x152cc0(GFP_USER|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 7358, tgid 7350 (syz-executor.0), ts 175681974997, free_ts 175582496153 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x1f3/0x230 mm/page_alloc.c:1468 prep_new_page mm/page_alloc.c:1476 [inline] get_page_from_freelist+0x2e43/0x2f00 mm/page_alloc.c:3420 __alloc_pages_noprof+0x256/0x6c0 mm/page_alloc.c:4678 __alloc_pages_node_noprof include/linux/gfp.h:269 [inline] alloc_pages_node_noprof include/linux/gfp.h:296 [inline] alloc_slab_page+0x5f/0x120 mm/slub.c:2265 allocate_slab+0x5a/0x2f0 mm/slub.c:2428 new_slab mm/slub.c:2481 [inline] ___slab_alloc+0xcd1/0x14b0 mm/slub.c:3667 __slab_alloc+0x58/0xa0 mm/slub.c:3757 __slab_alloc_node mm/slub.c:3810 [inline] slab_alloc_node mm/slub.c:3989 [inline] kmem_cache_alloc_node_noprof+0x1fe/0x320 mm/slub.c:4044 __alloc_skb+0x1c3/0x440 net/core/skbuff.c:656 alloc_skb include/linux/skbuff.h:1308 [inline] bt_skb_alloc include/net/bluetooth/bluetooth.h:489 [inline] vhci_get_user drivers/bluetooth/hci_vhci.c:489 [inline] vhci_write+0xc0/0x480 drivers/bluetooth/hci_vhci.c:609 do_iter_readv_writev+0x5a4/0x800 vfs_writev+0x395/0xbe0 fs/read_write.c:971 do_writev+0x1b1/0x350 fs/read_write.c:1018 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] __do_fast_syscall_32+0xb4/0x120 arch/x86/entry/common.c:386 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e page last free pid 7356 tgid 7355 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1088 [inline] free_unref_page+0xd22/0xea0 mm/page_alloc.c:2583 tlb_batch_list_free mm/mmu_gather.c:159 [inline] tlb_finish_mmu+0x11f/0x200 mm/mmu_gather.c:468 exit_mmap+0x44f/0xc80 mm/mmap.c:3354 __mmput+0x115/0x3c0 kernel/fork.c:1346 exit_mm+0x220/0x310 kernel/exit.c:565 do_exit+0x9aa/0x27e0 kernel/exit.c:861 do_group_exit+0x207/0x2c0 kernel/exit.c:1023 get_signal+0x16a1/0x1740 kernel/signal.c:2909 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_fast_syscall_32+0xc4/0x120 arch/x86/entry/common.c:389 do_fast_syscall_32+0x34/0x80 arch/x86/entry/common.c:411 entry_SYSENTER_compat_after_hwframe+0x84/0x8e Memory state around the buggy address: ffff88807d545900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88807d545980: 00 00 00 00 00 00 fc fc fc fc fc fc fc fc fc fc >ffff88807d545a00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807d545a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ffff88807d545b00: fc fc fc fc fc fc fc fc 00 00 00 00 00 00 00 00 ==================================================================