================================================================== BUG: KASAN: use-after-free in nfc_llcp_find_local+0xf0/0xfc net/nfc/llcp_core.c:285 Read of size 8 at addr ffff00001cc91000 by task syz-executor.0/29753 CPU: 0 PID: 29753 Comm: syz-executor.0 Not tainted 6.2.0-rc1-syzkaller-00095-ge4cf7c25bae5 #0 Hardware name: linux,dummy-virt (DT) Call trace: dump_backtrace+0xe0/0x140 arch/arm64/kernel/stacktrace.c:156 show_stack+0x18/0x30 arch/arm64/kernel/stacktrace.c:163 __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x9c/0xd8 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:306 [inline] print_report+0x194/0x494 mm/kasan/report.c:417 kasan_report+0xa4/0x22c mm/kasan/report.c:517 __asan_report_load8_noabort+0x28/0x3c mm/kasan/report_generic.c:351 nfc_llcp_find_local+0xf0/0xfc net/nfc/llcp_core.c:285 nfc_llcp_unregister_device+0x10/0x20c net/nfc/llcp_core.c:1610 nfc_unregister_device+0x120/0x2a0 net/nfc/core.c:1179 nci_unregister_device+0x1bc/0x280 net/nfc/nci/core.c:1303 virtual_ncidev_close+0x48/0xb0 drivers/nfc/virtual_ncidev.c:163 __fput+0x1ac/0x860 fs/file_table.c:320 ____fput+0x10/0x1c fs/file_table.c:348 task_work_run+0x12c/0x220 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x920/0x2870 arch/arm64/kernel/signal.c:1132 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x11c/0x140 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0xb8/0xc0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584 Allocated by task 29767: kasan_save_stack+0x2c/0x60 mm/kasan/common.c:45 kasan_set_track+0x2c/0x40 mm/kasan/common.c:52 kasan_save_alloc_info+0x24/0x34 mm/kasan/generic.c:507 ____kasan_kmalloc mm/kasan/common.c:371 [inline] __kasan_kmalloc+0xa0/0xc0 mm/kasan/common.c:380 kasan_kmalloc include/linux/kasan.h:211 [inline] kmalloc_trace+0x8c/0xa0 mm/slab_common.c:1067 kmalloc include/linux/slab.h:580 [inline] kzalloc include/linux/slab.h:720 [inline] nfc_llcp_register_device+0x44/0x7e4 net/nfc/llcp_core.c:1566 nfc_register_device+0x78/0x320 net/nfc/core.c:1124 nci_register_device+0x604/0x8c0 net/nfc/nci/core.c:1257 virtual_ncidev_open+0x110/0x1d4 drivers/nfc/virtual_ncidev.c:148 misc_open+0x294/0x394 drivers/char/misc.c:165 chrdev_open+0x1c0/0x544 fs/char_dev.c:414 do_dentry_open+0x3c4/0xf40 fs/open.c:882 vfs_open+0x90/0xd0 fs/open.c:1013 do_open fs/namei.c:3557 [inline] path_openat+0x10cc/0x2010 fs/namei.c:3714 do_filp_open+0x154/0x330 fs/namei.c:3741 do_sys_openat2+0x124/0x390 fs/open.c:1310 do_sys_open fs/open.c:1326 [inline] __do_sys_openat fs/open.c:1342 [inline] __se_sys_openat fs/open.c:1337 [inline] __arm64_sys_openat+0x130/0x1c0 fs/open.c:1337 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall+0x6c/0x260 arch/arm64/kernel/syscall.c:52 el0_svc_common.constprop.0+0xc4/0x254 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x50/0x15c arch/arm64/kernel/syscall.c:197 el0_svc+0x54/0x140 arch/arm64/kernel/entry-common.c:637 el0t_64_sync_handler+0xb8/0xc0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584 Freed by task 29765: kasan_save_stack+0x2c/0x60 mm/kasan/common.c:45 kasan_set_track+0x2c/0x40 mm/kasan/common.c:52 kasan_save_free_info+0x38/0x5c mm/kasan/generic.c:518 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x124/0x1f0 mm/kasan/common.c:200 __kasan_slab_free+0x18/0x24 mm/kasan/common.c:244 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x9c/0x1bc mm/slub.c:1807 slab_free mm/slub.c:3787 [inline] __kmem_cache_free+0xa4/0x370 mm/slub.c:3800 kfree+0xdc/0x284 mm/slab_common.c:1020 local_release net/nfc/llcp_core.c:173 [inline] kref_put include/linux/kref.h:65 [inline] nfc_llcp_local_put net/nfc/llcp_core.c:181 [inline] nfc_llcp_local_put net/nfc/llcp_core.c:176 [inline] nfc_llcp_unregister_device+0x15c/0x20c net/nfc/llcp_core.c:1619 nfc_unregister_device+0x120/0x2a0 net/nfc/core.c:1179 nci_unregister_device+0x1bc/0x280 net/nfc/nci/core.c:1303 virtual_ncidev_close+0x48/0xb0 drivers/nfc/virtual_ncidev.c:163 __fput+0x1ac/0x860 fs/file_table.c:320 ____fput+0x10/0x1c fs/file_table.c:348 task_work_run+0x12c/0x220 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x920/0x2870 arch/arm64/kernel/signal.c:1132 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x11c/0x140 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0xb8/0xc0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584 Last potentially related work creation: kasan_save_stack+0x2c/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb8/0xf0 mm/kasan/generic.c:488 kasan_record_aux_stack_noalloc+0x14/0x20 mm/kasan/generic.c:498 __call_rcu_common.constprop.0+0x9c/0x970 kernel/rcu/tree.c:2755 call_rcu+0x10/0x20 kernel/rcu/tree.c:2868 keypair_free_kref drivers/net/wireguard/noise.c:128 [inline] kref_put include/linux/kref.h:65 [inline] wg_noise_keypair_put+0xec/0x2a0 drivers/net/wireguard/noise.c:139 add_new_keypair drivers/net/wireguard/noise.c:237 [inline] wg_noise_handshake_begin_session+0x4e4/0xa20 drivers/net/wireguard/noise.c:845 wg_receive_handshake_packet+0x2a8/0x7c0 drivers/net/wireguard/receive.c:176 wg_packet_handshake_receive_worker+0xd8/0x2ec drivers/net/wireguard/receive.c:213 process_one_work+0x780/0x184c kernel/workqueue.c:2289 worker_thread+0x3cc/0xc40 kernel/workqueue.c:2436 kthread+0x23c/0x2a0 kernel/kthread.c:376 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:863 Second to last potentially related work creation: kasan_save_stack+0x2c/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb8/0xf0 mm/kasan/generic.c:488 kasan_record_aux_stack_noalloc+0x14/0x20 mm/kasan/generic.c:498 __call_rcu_common.constprop.0+0x9c/0x970 kernel/rcu/tree.c:2755 call_rcu+0x10/0x20 kernel/rcu/tree.c:2868 netlink_release+0x8b8/0x1380 net/netlink/af_netlink.c:826 __sock_release+0xa0/0x214 net/socket.c:650 sock_close+0x18/0x2c net/socket.c:1365 __fput+0x1ac/0x860 fs/file_table.c:320 ____fput+0x10/0x1c fs/file_table.c:348 task_work_run+0x12c/0x220 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x920/0x2870 arch/arm64/kernel/signal.c:1132 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x11c/0x140 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0xb8/0xc0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584 The buggy address belongs to the object at ffff00001cc91000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 0 bytes inside of 2048-byte region [ffff00001cc91000, ffff00001cc91800) The buggy address belongs to the physical page: page:000000003e9edaf9 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5cc90 head:000000003e9edaf9 order:3 compound_mapcount:0 subpages_mapcount:0 compound_pincount:0 flags: 0x1ffc00000010200(slab|head|node=0|zone=0|lastcpupid=0x7ff) raw: 01ffc00000010200 ffff000009402900 fffffc0000670000 dead000000000002 raw: 0000000000000000 0000000080080008 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff00001cc90f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff00001cc90f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff00001cc91000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff00001cc91080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff00001cc91100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ================================================================== Unable to handle kernel paging request at virtual address dfff800000000002 KASAN: null-ptr-deref in range [0x0000000000000010-0x0000000000000017] Mem abort info: ESR = 0x0000000096000006 EC = 0x25: DABT (current EL), IL = 32 bits SET = 0, FnV = 0 EA = 0, S1PTW = 0 FSC = 0x06: level 2 translation fault Data abort info: ISV = 0, ISS = 0x00000006 CM = 0, WnR = 0 [dfff800000000002] address between user and kernel address ranges Internal error: Oops: 0000000096000006 [#1] PREEMPT SMP Modules linked in: CPU: 1 PID: 29753 Comm: syz-executor.0 Tainted: G B 6.2.0-rc1-syzkaller-00095-ge4cf7c25bae5 #0 Hardware name: linux,dummy-virt (DT) pstate: 00000005 (nzcv daif -PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : nfc_llcp_find_local+0x54/0xfc net/nfc/llcp_core.c:286 lr : nfc_llcp_find_local+0xf0/0xfc net/nfc/llcp_core.c:285 sp : ffff800011e47970 x29: ffff800011e47970 x28: ffff00000ef1a000 x27: ffff0000160f5220 x26: ffff00001b9f5038 x25: 1fffe0000373ea07 x24: 1fffe00002be6e34 x23: ffff00001b9f0600 x22: ffff00001b9f0000 x21: ffff80000f681340 x20: dfff800000000000 x19: 0000000000000000 x18: ffff00006a969c00 x17: 0000000000000000 x16: 0000000000000000 x15: 0000000000000000 x14: 0000000000000000 x13: 205d333537393254 x12: ffff700001efb915 x11: 1ffff00001efb914 x10: ffff700001efb914 x9 : dfff800000000000 x8 : ffff80000f7dc8a7 x7 : 00008ffffe1046ec x6 : 0000000000000001 x5 : ffff80000f7dc8a0 x4 : 0000000000000000 x3 : 0000000000000000 x2 : 0000000000000002 x1 : ffff800010bec548 x0 : 0000000000000010 Call trace: nfc_llcp_find_local+0x54/0xfc net/nfc/llcp_core.c:286 nfc_llcp_unregister_device+0x10/0x20c net/nfc/llcp_core.c:1610 nfc_unregister_device+0x120/0x2a0 net/nfc/core.c:1179 nci_unregister_device+0x1bc/0x280 net/nfc/nci/core.c:1303 virtual_ncidev_close+0x48/0xb0 drivers/nfc/virtual_ncidev.c:163 __fput+0x1ac/0x860 fs/file_table.c:320 ____fput+0x10/0x1c fs/file_table.c:348 task_work_run+0x12c/0x220 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] do_notify_resume+0x920/0x2870 arch/arm64/kernel/signal.c:1132 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline] exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline] el0_svc+0x11c/0x140 arch/arm64/kernel/entry-common.c:638 el0t_64_sync_handler+0xb8/0xc0 arch/arm64/kernel/entry-common.c:655 el0t_64_sync+0x190/0x194 arch/arm64/kernel/entry.S:584 Code: eb15027f 540001e0 91004260 d343fc02 (38f46842) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: eb15027f cmp x19, x21 4: 540001e0 b.eq 0x40 // b.none 8: 91004260 add x0, x19, #0x10 c: d343fc02 lsr x2, x0, #3 * 10: 38f46842 ldrsb w2, [x2, x20] <-- trapping instruction