================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read include/linux/instrumented.h:68 [inline] BUG: KASAN: slab-use-after-free in atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] BUG: KASAN: slab-use-after-free in refcount_read include/linux/refcount.h:136 [inline] BUG: KASAN: slab-use-after-free in skb_unref include/linux/skbuff.h:1222 [inline] BUG: KASAN: slab-use-after-free in __kfree_skb_reason net/core/skbuff.c:1195 [inline] BUG: KASAN: slab-use-after-free in kfree_skb_reason+0x41/0x3b0 net/core/skbuff.c:1222 Read of size 4 at addr ffff88801fd409a4 by task syz-executor.3/5108 CPU: 1 PID: 5108 Comm: syz-executor.3 Not tainted 6.10.0-rc3-syzkaller-00044-g2ccbdf43d5e7 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 06/07/2024 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 kasan_check_range+0x282/0x290 mm/kasan/generic.c:189 instrument_atomic_read include/linux/instrumented.h:68 [inline] atomic_read include/linux/atomic/atomic-instrumented.h:32 [inline] refcount_read include/linux/refcount.h:136 [inline] skb_unref include/linux/skbuff.h:1222 [inline] __kfree_skb_reason net/core/skbuff.c:1195 [inline] kfree_skb_reason+0x41/0x3b0 net/core/skbuff.c:1222 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 RIP: 0023:0xf7494579 Code: b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 00 00 00 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 RSP: 002b:00000000ffa13f44 EFLAGS: 00000206 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00000000400448dd RDX: 00000000ffa13f94 RSI: 00000000f7484ff4 RDI: 0000000000000004 RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Allocated by task 53: 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 5116: 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_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 The buggy address belongs to the object at ffff88801fd408c0 which belongs to the cache skbuff_head_cache of size 240 The buggy address is located 228 bytes inside of freed 240-byte region [ffff88801fd408c0, ffff88801fd409b0) The buggy address belongs to the physical page: page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1fd40 flags: 0xfff00000000000(node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffefff(slab) raw: 00fff00000000000 ffff888018ad7780 dead000000000122 0000000000000000 raw: 0000000000000000 00000000800c000c 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 0x52cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP), pid 53, tgid 53 (kworker/u9:0), ts 53846136221, free_ts 53804707100 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_noprof+0x1c1/0x2a0 mm/slub.c:4008 skb_clone+0x20c/0x390 net/core/skbuff.c:2052 hci_event_packet+0x49c/0x1540 net/bluetooth/hci_event.c:7460 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 page last free pid 5104 tgid 5104 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 __folio_put+0x3b9/0x620 mm/swap.c:129 skb_page_unref include/linux/skbuff_ref.h:44 [inline] __skb_frag_unref include/linux/skbuff_ref.h:57 [inline] skb_release_data+0x467/0x880 net/core/skbuff.c:1102 skb_release_all net/core/skbuff.c:1173 [inline] napi_consume_skb+0x146/0x1f0 net/core/skbuff.c:1489 skb_defer_free_flush net/core/dev.c:6270 [inline] net_rx_action+0x584/0x10a0 net/core/dev.c:6888 handle_softirqs+0x2c4/0x970 kernel/softirq.c:554 do_softirq+0x11b/0x1e0 kernel/softirq.c:455 __local_bh_enable_ip+0x1bb/0x200 kernel/softirq.c:382 local_bh_enable include/linux/bottom_half.h:33 [inline] fpregs_unlock arch/x86/include/asm/fpu/api.h:80 [inline] fpu_clone+0x3ee/0xad0 arch/x86/kernel/fpu/core.c:634 copy_thread+0x3e5/0x980 arch/x86/kernel/process.c:214 copy_process+0x1c0c/0x3dc0 kernel/fork.c:2399 kernel_clone+0x226/0x8f0 kernel/fork.c:2797 __do_compat_sys_ia32_clone arch/x86/kernel/sys_ia32.c:254 [inline] __se_compat_sys_ia32_clone arch/x86/kernel/sys_ia32.c:240 [inline] __ia32_compat_sys_ia32_clone+0x255/0x2a0 arch/x86/kernel/sys_ia32.c:240 do_syscall_32_irqs_on arch/x86/entry/common.c:165 [inline] do_int80_emulation+0x11f/0x200 arch/x86/entry/common.c:253 asm_int80_emulation+0x1a/0x20 arch/x86/include/asm/idtentry.h:626 Memory state around the buggy address: ffff88801fd40880: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb ffff88801fd40900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88801fd40980: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc ^ ffff88801fd40a00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88801fd40a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc ================================================================== ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 90 nop 33: 90 nop 34: 90 nop 35: 90 nop 36: 90 nop 37: 90 nop 38: 90 nop 39: 90 nop 3a: 90 nop 3b: 90 nop 3c: 90 nop 3d: 90 nop