================================================================== BUG: KASAN: slab-use-after-free in nfc_llcp_find_local+0xc5/0xe0 net/nfc/llcp_core.c:287 Read of size 8 at addr ffff88807b35e010 by task syz-executor.3/6883 CPU: 0 PID: 6883 Comm: syz-executor.3 Not tainted 6.3.0-next-20230505-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/14/2023 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:351 print_report mm/kasan/report.c:462 [inline] kasan_report+0x11c/0x130 mm/kasan/report.c:572 nfc_llcp_find_local+0xc5/0xe0 net/nfc/llcp_core.c:287 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+0x210/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 do_syscall_64+0x46/0xb0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f5ff2a3e01b 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:00007ffc489eac30 EFLAGS: 00000293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 000000000000000a RCX: 00007f5ff2a3e01b RDX: 0000000000000000 RSI: 0000001b2d524dc8 RDI: 0000000000000009 RBP: 00007f5ff2bad980 R08: 0000000000000000 R09: 00000000b9f5f90a R10: 0000000000000000 R11: 0000000000000293 R12: 000000000001f285 R13: 00007ffc489ead30 R14: 00007f5ff2bac1f0 R15: 0000000000000032 Allocated by task 6901: 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+0xa2/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:559 [inline] kzalloc include/linux/slab.h:680 [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:3636 [inline] path_openat+0x1baa/0x2750 fs/namei.c:3791 do_filp_open+0x1ba/0x410 fs/namei.c:3818 do_sys_openat2+0x16d/0x4c0 fs/open.c:1356 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x143/0x1f0 fs/open.c:1383 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 6879: kasan_save_stack+0x22/0x40 mm/kasan/common.c:45 kasan_set_track+0x25/0x30 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x40 mm/kasan/generic.c:521 ____kasan_slab_free mm/kasan/common.c:236 [inline] ____kasan_slab_free+0x160/0x1c0 mm/kasan/common.c:200 kasan_slab_free include/linux/kasan.h:162 [inline] slab_free_hook mm/slub.c:1781 [inline] slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1807 slab_free mm/slub.c:3786 [inline] __kmem_cache_free+0xaf/0x2d0 mm/slub.c:3799 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+0x210/0x240 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline] syscall_exit_to_user_mode+0x1d/0x50 kernel/entry/common.c:297 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 ffff88807b35e000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 16 bytes inside of freed 2048-byte region [ffff88807b35e000, ffff88807b35e800) The buggy address belongs to the physical page: page:ffffea0001ecd600 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88807b359000 pfn:0x7b358 head:ffffea0001ecd600 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000010200 ffff888012442000 ffffea0000838a00 dead000000000002 raw: ffff88807b359000 0000000080080003 00000001ffffffff 0000000000000000 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 901, tgid 901 (kworker/0:2), ts 106127709283, free_ts 106030461675 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x2db/0x350 mm/page_alloc.c:1731 prep_new_page mm/page_alloc.c:1738 [inline] get_page_from_freelist+0xf7c/0x2aa0 mm/page_alloc.c:3502 __alloc_pages+0x1cb/0x4a0 mm/page_alloc.c:4768 alloc_pages+0x1aa/0x270 mm/mempolicy.c:2279 alloc_slab_page mm/slub.c:1851 [inline] allocate_slab+0x28e/0x380 mm/slub.c:1998 new_slab mm/slub.c:2051 [inline] ___slab_alloc+0xa91/0x1400 mm/slub.c:3192 __slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3291 __slab_alloc_node mm/slub.c:3344 [inline] slab_alloc_node mm/slub.c:3441 [inline] __kmem_cache_alloc_node+0x136/0x320 mm/slub.c:3490 __do_kmalloc_node mm/slab_common.c:965 [inline] __kmalloc_node_track_caller+0x4f/0x1a0 mm/slab_common.c:986 kmalloc_reserve+0xf0/0x270 net/core/skbuff.c:585 __alloc_skb+0x129/0x330 net/core/skbuff.c:654 alloc_skb include/linux/skbuff.h:1288 [inline] alloc_skb_with_frags+0x9a/0x6c0 net/core/skbuff.c:6378 sock_alloc_send_pskb+0x7a7/0x930 net/core/sock.c:2729 sock_alloc_send_skb include/net/sock.h:1860 [inline] mld_newpack.isra.0+0x1b9/0x760 net/ipv6/mcast.c:1748 add_grhead+0x295/0x340 net/ipv6/mcast.c:1851 add_grec+0x1053/0x1610 net/ipv6/mcast.c:1989 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1302 [inline] free_unref_page_prepare+0x4dd/0xb90 mm/page_alloc.c:2564 free_unref_page+0x33/0x370 mm/page_alloc.c:2659 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x195/0x220 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x63/0x90 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:186 [inline] slab_post_alloc_hook mm/slab.h:711 [inline] slab_alloc_node mm/slub.c:3451 [inline] kmem_cache_alloc_node+0x185/0x3e0 mm/slub.c:3496 __alloc_skb+0x288/0x330 net/core/skbuff.c:644 alloc_skb include/linux/skbuff.h:1288 [inline] alloc_skb_with_frags+0x9a/0x6c0 net/core/skbuff.c:6378 sock_alloc_send_pskb+0x7a7/0x930 net/core/sock.c:2729 unix_dgram_sendmsg+0x41b/0x1950 net/unix/af_unix.c:1944 sock_sendmsg_nosec net/socket.c:724 [inline] sock_sendmsg+0xde/0x190 net/socket.c:747 __sys_sendto+0x23a/0x340 net/socket.c:2144 __do_sys_sendto net/socket.c:2156 [inline] __se_sys_sendto net/socket.c:2152 [inline] __x64_sys_sendto+0xe1/0x1b0 net/socket.c:2152 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: ffff88807b35df00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807b35df80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff88807b35e000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807b35e080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807b35e100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================