================================================================== BUG: KASAN: slab-use-after-free in instrument_atomic_read_write include/linux/instrumented.h:96 [inline] BUG: KASAN: slab-use-after-free in atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:252 [inline] BUG: KASAN: slab-use-after-free in __refcount_add include/linux/refcount.h:193 [inline] BUG: KASAN: slab-use-after-free in __refcount_inc include/linux/refcount.h:250 [inline] BUG: KASAN: slab-use-after-free in refcount_inc include/linux/refcount.h:267 [inline] BUG: KASAN: slab-use-after-free in sock_hold include/net/sock.h:777 [inline] BUG: KASAN: slab-use-after-free in sco_sock_timeout+0x64/0x25c net/bluetooth/sco.c:88 Write of size 4 at addr ffff0000d838e080 by task kworker/0:1/10 CPU: 0 PID: 10 Comm: kworker/0:1 Not tainted 6.6.0-rc7-syzkaller-g8de1e7afcc1c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Workqueue: events sco_sock_timeout Call trace: dump_backtrace+0x1b8/0x1e4 arch/arm64/kernel/stacktrace.c:233 show_stack+0x2c/0x44 arch/arm64/kernel/stacktrace.c:240 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd0/0x124 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0x174/0x514 mm/kasan/report.c:475 kasan_report+0xd8/0x138 mm/kasan/report.c:588 kasan_check_range+0x254/0x294 mm/kasan/generic.c:187 __kasan_check_write+0x20/0x30 mm/kasan/shadow.c:37 instrument_atomic_read_write include/linux/instrumented.h:96 [inline] atomic_fetch_add_relaxed include/linux/atomic/atomic-instrumented.h:252 [inline] __refcount_add include/linux/refcount.h:193 [inline] __refcount_inc include/linux/refcount.h:250 [inline] refcount_inc include/linux/refcount.h:267 [inline] sock_hold include/net/sock.h:777 [inline] sco_sock_timeout+0x64/0x25c net/bluetooth/sco.c:88 process_one_work+0x694/0x1204 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x938/0xef4 kernel/workqueue.c:2784 kthread+0x288/0x310 kernel/kthread.c:388 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:857 Allocated by task 6176: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x7c mm/kasan/common.c:52 kasan_save_alloc_info+0x24/0x30 mm/kasan/generic.c:511 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0xac/0xc4 mm/kasan/common.c:383 kasan_kmalloc include/linux/kasan.h:198 [inline] __do_kmalloc_node mm/slab_common.c:1026 [inline] __kmalloc+0xcc/0x1b8 mm/slab_common.c:1039 kmalloc include/linux/slab.h:603 [inline] sk_prot_alloc+0xc4/0x1f0 net/core/sock.c:2090 sk_alloc+0x44/0x3f4 net/core/sock.c:2143 bt_sock_alloc+0x4c/0x32c net/bluetooth/af_bluetooth.c:148 sco_sock_alloc net/bluetooth/sco.c:495 [inline] sco_sock_create+0xbc/0x31c net/bluetooth/sco.c:526 bt_sock_create+0x14c/0x248 net/bluetooth/af_bluetooth.c:132 __sock_create+0x43c/0x884 net/socket.c:1569 sock_create net/socket.c:1620 [inline] __sys_socket_create net/socket.c:1657 [inline] __sys_socket+0x134/0x340 net/socket.c:1708 __do_sys_socket net/socket.c:1722 [inline] __se_sys_socket net/socket.c:1720 [inline] __arm64_sys_socket+0x7c/0x94 net/socket.c:1720 __invoke_syscall arch/arm64/kernel/syscall.c:37 [inline] invoke_syscall+0x98/0x2b8 arch/arm64/kernel/syscall.c:51 el0_svc_common+0x130/0x23c arch/arm64/kernel/syscall.c:136 do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:155 el0_svc+0x54/0x158 arch/arm64/kernel/entry-common.c:678 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 Freed by task 6176: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4c/0x7c mm/kasan/common.c:52 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:522 ____kasan_slab_free+0x144/0x1c0 mm/kasan/common.c:236 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1800 [inline] slab_free_freelist_hook mm/slub.c:1826 [inline] slab_free mm/slub.c:3809 [inline] __kmem_cache_free+0x2ac/0x480 mm/slub.c:3822 kfree+0xb8/0x19c mm/slab_common.c:1075 sk_prot_free net/core/sock.c:2126 [inline] __sk_destruct+0x4c0/0x770 net/core/sock.c:2218 sk_destruct net/core/sock.c:2233 [inline] __sk_free+0x37c/0x4e8 net/core/sock.c:2244 sk_free+0x60/0xc8 net/core/sock.c:2255 sock_put include/net/sock.h:1989 [inline] sco_sock_kill+0xfc/0x1b4 net/bluetooth/sco.c:426 sco_sock_release+0x1fc/0x2c0 net/bluetooth/sco.c:1256 __sock_release net/socket.c:659 [inline] sock_close+0xa4/0x1e8 net/socket.c:1419 __fput+0x324/0x7f8 fs/file_table.c:384 ____fput+0x20/0x30 fs/file_table.c:412 task_work_run+0x230/0x2e0 kernel/task_work.c:180 get_signal+0x13f4/0x15ec kernel/signal.c:2668 do_signal arch/arm64/kernel/signal.c:1249 [inline] do_notify_resume+0x3bc/0x393c arch/arm64/kernel/signal.c:1302 exit_to_user_mode_prepare arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:144 [inline] el0_svc+0x9c/0x158 arch/arm64/kernel/entry-common.c:679 el0t_64_sync_handler+0x84/0xfc arch/arm64/kernel/entry-common.c:696 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:595 The buggy address belongs to the object at ffff0000d838e000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 128 bytes inside of freed 2048-byte region [ffff0000d838e000, ffff0000d838e800) The buggy address belongs to the physical page: page:00000000b7684586 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x118388 head:00000000b7684586 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x5ffc00000000840(slab|head|node=0|zone=2|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 05ffc00000000840 ffff0000c0002000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000080008 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff0000d838df80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff0000d838e000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff0000d838e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff0000d838e100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff0000d838e180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== ------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 0 PID: 10 at lib/refcount.c:25 refcount_warn_saturate+0x1a8/0x20c lib/refcount.c:25 Modules linked in: CPU: 0 PID: 10 Comm: kworker/0:1 Tainted: G B 6.6.0-rc7-syzkaller-g8de1e7afcc1c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Workqueue: events sco_sock_timeout pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : refcount_warn_saturate+0x1a8/0x20c lib/refcount.c:25 lr : refcount_warn_saturate+0x1a8/0x20c lib/refcount.c:25 sp : ffff800092d57af0 x29: ffff800092d57af0 x28: 1fffe0001accda8a x27: dfff800000000000 x26: ffff0000c1084008 x25: ffff0000d666d450 x24: ffff0001b418b500 x23: dfff800000000000 x22: 0000000000000000 x21: 0000000000000002 x20: ffff0000d838e080 x19: ffff8000910a2000 x18: ffff800092d57800 x17: 0000000000000000 x16: ffff80008a668900 x15: 0000000000000001 x14: 1ffff000125aae78 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000001 x10: 0000000000000000 x9 : 84f4767814214800 x8 : 84f4767814214800 x7 : 0000000000000001 x6 : 0000000000000001 x5 : ffff800092d573d8 x4 : ffff80008e4210a0 x3 : ffff8000803639bc x2 : 0000000000000001 x1 : 0000000000000001 x0 : 0000000000000000 Call trace: refcount_warn_saturate+0x1a8/0x20c lib/refcount.c:25 __refcount_inc include/linux/refcount.h:250 [inline] refcount_inc include/linux/refcount.h:267 [inline] sock_hold include/net/sock.h:777 [inline] sco_sock_timeout+0x19c/0x25c net/bluetooth/sco.c:88 process_one_work+0x694/0x1204 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x938/0xef4 kernel/workqueue.c:2784 kthread+0x288/0x310 kernel/kthread.c:388 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:857 irq event stamp: 49441 hardirqs last enabled at (49441): [] __exit_to_kernel_mode arch/arm64/kernel/entry-common.c:84 [inline] hardirqs last enabled at (49441): [] exit_to_kernel_mode+0xdc/0x10c arch/arm64/kernel/entry-common.c:94 hardirqs last disabled at (49440): [] __do_softirq+0x950/0xd54 kernel/softirq.c:569 softirqs last enabled at (49376): [] spin_unlock_bh include/linux/spinlock.h:396 [inline] softirqs last enabled at (49376): [] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] softirqs last enabled at (49376): [] nsim_dev_trap_report_work+0x620/0x924 drivers/net/netdevsim/dev.c:850 softirqs last disabled at (49374): [] spin_lock_bh include/linux/spinlock.h:356 [inline] softirqs last disabled at (49374): [] nsim_dev_trap_report drivers/net/netdevsim/dev.c:816 [inline] softirqs last disabled at (49374): [] nsim_dev_trap_report_work+0x59c/0x924 drivers/net/netdevsim/dev.c:850 ---[ end trace 0000000000000000 ]--- ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 0 PID: 10 at lib/refcount.c:28 refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28 Modules linked in: CPU: 0 PID: 10 Comm: kworker/0:1 Tainted: G B W 6.6.0-rc7-syzkaller-g8de1e7afcc1c #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Workqueue: events sco_sock_timeout pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28 lr : refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28 sp : ffff800092d57af0 x29: ffff800092d57af0 x28: 1fffe0001accda8a x27: dfff800000000000 x26: ffff0000c1084008 x25: ffff0000d666d450 x24: ffff0001b418b500 x23: dfff800000000000 x22: 0000000000000000 x21: 0000000000000003 x20: ffff0000d838e080 x19: ffff8000910a2000 x18: 1fffe0003682efce x17: 0000000000000000 x16: ffff80008a71b23c x15: 0000000000000001 x14: 1fffe0003682f032 x13: 0000000000000000 x12: 0000000000000000 x11: 0000000000000000 x10: 0000000000000000 x9 : 84f4767814214800 x8 : 84f4767814214800 x7 : 0000000000000001 x6 : 0000000000000001 x5 : ffff800092d573d8 x4 : ffff80008e4210a0 x3 : ffff8000805a359c x2 : 0000000000000001 x1 : 0000000100000000 x0 : 0000000000000000 Call trace: refcount_warn_saturate+0x1c8/0x20c lib/refcount.c:28 __refcount_sub_and_test include/linux/refcount.h:283 [inline] __refcount_dec_and_test include/linux/refcount.h:315 [inline] refcount_dec_and_test include/linux/refcount.h:333 [inline] sock_put include/net/sock.h:1988 [inline] sco_sock_timeout+0x1b0/0x25c net/bluetooth/sco.c:100 process_one_work+0x694/0x1204 kernel/workqueue.c:2630 process_scheduled_works kernel/workqueue.c:2703 [inline] worker_thread+0x938/0xef4 kernel/workqueue.c:2784 kthread+0x288/0x310 kernel/kthread.c:388 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:857 irq event stamp: 49441 hardirqs last enabled at (49441): [] __exit_to_kernel_mode arch/arm64/kernel/entry-common.c:84 [inline] hardirqs last enabled at (49441): [] exit_to_kernel_mode+0xdc/0x10c arch/arm64/kernel/entry-common.c:94 hardirqs last disabled at (49440): [] __do_softirq+0x950/0xd54 kernel/softirq.c:569 softirqs last enabled at (49376): [] spin_unlock_bh include/linux/spinlock.h:396 [inline] softirqs last enabled at (49376): [] nsim_dev_trap_report drivers/net/netdevsim/dev.c:820 [inline] softirqs last enabled at (49376): [] nsim_dev_trap_report_work+0x620/0x924 drivers/net/netdevsim/dev.c:850 softirqs last disabled at (49374): [] spin_lock_bh include/linux/spinlock.h:356 [inline] softirqs last disabled at (49374): [] nsim_dev_trap_report drivers/net/netdevsim/dev.c:816 [inline] softirqs last disabled at (49374): [] nsim_dev_trap_report_work+0x59c/0x924 drivers/net/netdevsim/dev.c:850 ---[ end trace 0000000000000000 ]---