================================================================== BUG: KASAN: slab-use-after-free in nfc_llcp_find_local+0xcf/0xe0 net/nfc/llcp_core.c:286 Read of size 8 at addr ffff88802bdf9000 by task syz-executor.3/31930 CPU: 0 PID: 31930 Comm: syz-executor.3 Not tainted 6.2.0-syzkaller-13413-g0a3f9a6b0265 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/16/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x150 lib/dump_stack.c:106 print_address_description.constprop.0+0x2c/0x3c0 mm/kasan/report.c:319 print_report mm/kasan/report.c:430 [inline] kasan_report+0x11c/0x130 mm/kasan/report.c:536 nfc_llcp_find_local+0xcf/0xe0 net/nfc/llcp_core.c:286 nfc_llcp_unregister_device+0x1a/0x260 net/nfc/llcp_core.c:1611 nfc_unregister_device+0x196/0x330 net/nfc/core.c:1179 virtual_ncidev_close+0x52/0xb0 drivers/nfc/virtual_ncidev.c:163 __fput+0x27c/0xa90 fs/file_table.c:321 task_work_run+0x16f/0x270 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x23c/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fe00903dfab Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007ffd5969c230 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000005 RCX: 00007fe00903dfab RDX: 0000000000000000 RSI: 0000001b30d21dac RDI: 0000000000000004 RBP: 00007fe0091ad980 R08: 0000000000000000 R09: 000000005f033d0b R10: 0000000000000000 R11: 0000000000000293 R12: 00000000000739c2 R13: 00007ffd5969c330 R14: 00007fe0091ac050 R15: 0000000000000032 Allocated by task 31940: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] ____kasan_kmalloc mm/kasan/common.c:333 [inline] __kasan_kmalloc+0xa3/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:580 [inline] kzalloc include/linux/slab.h:720 [inline] nfc_llcp_register_device+0x49/0x9e0 net/nfc/llcp_core.c:1567 nfc_register_device+0x70/0x3c0 net/nfc/core.c:1124 nci_register_device+0x7cb/0xb50 net/nfc/nci/core.c:1257 virtual_ncidev_open+0x14f/0x230 drivers/nfc/virtual_ncidev.c:148 misc_open+0x37a/0x4a0 drivers/char/misc.c:165 chrdev_open+0x26a/0x770 fs/char_dev.c:414 do_dentry_open+0x6cc/0x13f0 fs/open.c:920 do_open fs/namei.c:3560 [inline] path_openat+0x1baa/0x2750 fs/namei.c:3715 do_filp_open+0x1ba/0x410 fs/namei.c:3742 do_sys_openat2+0x16d/0x4c0 fs/open.c:1348 do_sys_open fs/open.c:1364 [inline] __do_sys_openat fs/open.c:1380 [inline] __se_sys_openat fs/open.c:1375 [inline] __x64_sys_openat+0x143/0x1f0 fs/open.c:1375 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 31937: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:521 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x13b/0x1a0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] __cache_free mm/slab.c:3390 [inline] __do_kmem_cache_free mm/slab.c:3577 [inline] __kmem_cache_free+0xcd/0x2c0 mm/slab.c:3584 local_release net/nfc/llcp_core.c:174 [inline] kref_put include/linux/kref.h:65 [inline] nfc_llcp_local_put net/nfc/llcp_core.c:182 [inline] nfc_llcp_local_put net/nfc/llcp_core.c:177 [inline] nfc_llcp_unregister_device+0x1ba/0x260 net/nfc/llcp_core.c:1620 nfc_unregister_device+0x196/0x330 net/nfc/core.c:1179 virtual_ncidev_close+0x52/0xb0 drivers/nfc/virtual_ncidev.c:163 __fput+0x27c/0xa90 fs/file_table.c:321 task_work_run+0x16f/0x270 kernel/task_work.c:179 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop kernel/entry/common.c:171 [inline] exit_to_user_mode_prepare+0x23c/0x250 kernel/entry/common.c:203 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:296 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff88802bdf9000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 0 bytes inside of freed 2048-byte region [ffff88802bdf9000, ffff88802bdf9800) The buggy address belongs to the physical page: page:ffffea0000af7e40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2bdf9 flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000000200 ffff888012440800 ffffea000077a450 ffffea000177a610 raw: 0000000000000000 ffff88802bdf9000 0000000100000001 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 0x3420c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_COMP|__GFP_HARDWALL|__GFP_THISNODE), pid 28753, tgid 28751 (syz-executor.3), ts 442717808605, free_ts 442716817804 prep_new_page mm/page_alloc.c:2552 [inline] get_page_from_freelist+0x1190/0x2f80 mm/page_alloc.c:4325 __alloc_pages+0x1cb/0x5c0 mm/page_alloc.c:5591 __alloc_pages_node include/linux/gfp.h:237 [inline] kmem_getpages mm/slab.c:1360 [inline] cache_grow_begin+0x9b/0x3b0 mm/slab.c:2570 cache_alloc_refill+0x27f/0x380 mm/slab.c:2943 ____cache_alloc mm/slab.c:3019 [inline] ____cache_alloc mm/slab.c:3002 [inline] __do_cache_alloc mm/slab.c:3202 [inline] slab_alloc_node mm/slab.c:3250 [inline] __kmem_cache_alloc_node+0x360/0x3f0 mm/slab.c:3541 kmalloc_trace+0x26/0x60 mm/slab_common.c:1061 kmalloc include/linux/slab.h:580 [inline] kzalloc include/linux/slab.h:720 [inline] nfc_llcp_register_device+0x49/0x9e0 net/nfc/llcp_core.c:1567 nfc_register_device+0x70/0x3c0 net/nfc/core.c:1124 nci_register_device+0x7cb/0xb50 net/nfc/nci/core.c:1257 virtual_ncidev_open+0x14f/0x230 drivers/nfc/virtual_ncidev.c:148 misc_open+0x37a/0x4a0 drivers/char/misc.c:165 chrdev_open+0x26a/0x770 fs/char_dev.c:414 do_dentry_open+0x6cc/0x13f0 fs/open.c:920 do_open fs/namei.c:3560 [inline] path_openat+0x1baa/0x2750 fs/namei.c:3715 do_filp_open+0x1ba/0x410 fs/namei.c:3742 do_sys_openat2+0x16d/0x4c0 fs/open.c:1348 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1453 [inline] free_pcp_prepare+0x668/0xb50 mm/page_alloc.c:1503 free_unref_page_prepare mm/page_alloc.c:3387 [inline] free_unref_page+0x1d/0x490 mm/page_alloc.c:3482 vfree+0x180/0x7e0 mm/vmalloc.c:2742 copy_entries_to_user net/ipv4/netfilter/arp_tables.c:713 [inline] get_entries net/ipv4/netfilter/arp_tables.c:867 [inline] do_arpt_get_ctl+0x7b1/0x8f0 net/ipv4/netfilter/arp_tables.c:1453 nf_getsockopt+0x76/0xd0 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x189/0x1e0 net/ipv4/ip_sockglue.c:1815 tcp_getsockopt+0x99/0x100 net/ipv4/tcp.c:4409 __sys_getsockopt+0x21a/0x6a0 net/socket.c:2318 __do_sys_getsockopt net/socket.c:2333 [inline] __se_sys_getsockopt net/socket.c:2330 [inline] __x64_sys_getsockopt+0xbe/0x160 net/socket.c:2330 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff88802bdf8f00: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc ffff88802bdf8f80: 00 00 00 00 00 00 00 00 00 fc fc fc fc fc fc fc >ffff88802bdf9000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802bdf9080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88802bdf9100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================