================================================================== BUG: KASAN: slab-use-after-free in nfc_alloc_send_skb+0x189/0x1c0 net/nfc/core.c:726 Read of size 4 at addr ffff88806a407548 by task syz-executor.0/5449 CPU: 1 PID: 5449 Comm: syz-executor.0 Not tainted 6.6.0-rc7-syzkaller-00089-g8de1e7afcc1c-dirty #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0x163/0x540 mm/kasan/report.c:475 kasan_report+0x175/0x1b0 mm/kasan/report.c:588 nfc_alloc_send_skb+0x189/0x1c0 net/nfc/core.c:726 nfc_llcp_send_ui_frame+0x2ac/0x670 net/nfc/llcp_commands.c:766 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] ____sys_sendmsg+0x592/0x890 net/socket.c:2558 ___sys_sendmsg net/socket.c:2612 [inline] __sys_sendmmsg+0x3b2/0x730 net/socket.c:2698 __do_sys_sendmmsg net/socket.c:2727 [inline] __se_sys_sendmmsg net/socket.c:2724 [inline] __x64_sys_sendmmsg+0xa0/0xb0 net/socket.c:2724 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7efdd1e7cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007efdd2b050c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000133 RAX: ffffffffffffffda RBX: 00007efdd1f9bf80 RCX: 00007efdd1e7cae9 RDX: 0000000000000001 RSI: 00000000200013c0 RDI: 0000000000000004 RBP: 00007efdd1ec847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007efdd1f9bf80 R15: 00007ffcb9f3b548 Allocated by task 5449: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x98/0xb0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:599 [inline] kzalloc include/linux/slab.h:720 [inline] nfc_allocate_device+0x12f/0x520 net/nfc/core.c:1065 nci_allocate_device+0x1e2/0x360 net/nfc/nci/core.c:1179 virtual_ncidev_open+0x75/0x1b0 drivers/nfc/virtual_ncidev.c:136 misc_open+0x30b/0x380 drivers/char/misc.c:165 chrdev_open+0x551/0x630 fs/char_dev.c:414 do_dentry_open+0x80f/0x1430 fs/open.c:929 do_open fs/namei.c:3640 [inline] path_openat+0x27bb/0x3180 fs/namei.c:3797 do_filp_open+0x234/0x490 fs/namei.c:3824 do_sys_openat2+0x13e/0x1d0 fs/open.c:1422 do_sys_open fs/open.c:1437 [inline] __do_sys_openat fs/open.c:1453 [inline] __se_sys_openat fs/open.c:1448 [inline] __x64_sys_openat+0x247/0x290 fs/open.c:1448 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd Freed by task 5448: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4f/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x28/0x40 mm/kasan/generic.c:522 ____kasan_slab_free+0xd6/0x120 mm/kasan/common.c:236 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+0x25f/0x3b0 mm/slub.c:3822 device_release+0x95/0x1c0 kobject_cleanup lib/kobject.c:682 [inline] kobject_release lib/kobject.c:716 [inline] kref_put include/linux/kref.h:65 [inline] kobject_put+0x1ee/0x430 lib/kobject.c:733 nfc_free_device include/net/nfc/nfc.h:213 [inline] nci_free_device+0x38/0x50 net/nfc/nci/core.c:1209 virtual_ncidev_close+0x70/0x90 drivers/nfc/virtual_ncidev.c:164 __fput+0x3f8/0x910 fs/file_table.c:384 __do_sys_close fs/open.c:1572 [inline] __se_sys_close+0x15f/0x220 fs/open.c:1557 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x41/0xc0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd The buggy address belongs to the object at ffff88806a407000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1352 bytes inside of freed 2048-byte region [ffff88806a407000, ffff88806a407800) The buggy address belongs to the physical page: page:ffffea0001a90000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x6a400 head:ffffea0001a90000 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888012842000 dead000000000122 0000000000000000 raw: 0000000000000000 0000000000080008 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 5382, tgid 5382 (syz-executor.0), ts 87391067310, free_ts 58677729993 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1e6/0x210 mm/page_alloc.c:1536 prep_new_page mm/page_alloc.c:1543 [inline] get_page_from_freelist+0x31db/0x3360 mm/page_alloc.c:3170 __alloc_pages+0x255/0x670 mm/page_alloc.c:4426 alloc_slab_page+0x6a/0x160 mm/slub.c:1870 allocate_slab mm/slub.c:2017 [inline] new_slab+0x84/0x2f0 mm/slub.c:2070 ___slab_alloc+0xc85/0x1310 mm/slub.c:3223 __slab_alloc mm/slub.c:3322 [inline] __slab_alloc_node mm/slub.c:3375 [inline] slab_alloc_node mm/slub.c:3468 [inline] __kmem_cache_alloc_node+0x1af/0x270 mm/slub.c:3517 __do_kmalloc_node mm/slab_common.c:1025 [inline] __kmalloc+0xa8/0x230 mm/slab_common.c:1039 kmalloc include/linux/slab.h:603 [inline] kzalloc include/linux/slab.h:720 [inline] ipt_alloc_initial_table+0x6c/0x570 net/ipv4/netfilter/ip_tables.c:36 iptable_mangle_table_init+0x1c/0x60 net/ipv4/netfilter/iptable_mangle.c:88 xt_find_table_lock+0x2d0/0x3b0 net/netfilter/x_tables.c:1259 xt_request_find_table_lock+0x26/0x100 net/netfilter/x_tables.c:1284 get_info net/ipv4/netfilter/ip_tables.c:963 [inline] do_ipt_get_ctl+0x885/0x18c0 net/ipv4/netfilter/ip_tables.c:1651 nf_getsockopt+0x292/0x2c0 net/netfilter/nf_sockopt.c:116 ip_getsockopt+0x21e/0x2e0 net/ipv4/ip_sockglue.c:1788 tcp_getsockopt+0x160/0x1c0 net/ipv4/tcp.c:4278 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1136 [inline] free_unref_page_prepare+0x8c3/0x9f0 mm/page_alloc.c:2312 free_unref_page+0x37/0x3f0 mm/page_alloc.c:2405 vfree+0x186/0x2e0 mm/vmalloc.c:2842 kcov_put kernel/kcov.c:429 [inline] kcov_close+0x2b/0x50 kernel/kcov.c:525 __fput+0x3f8/0x910 fs/file_table.c:384 task_work_run+0x24a/0x300 kernel/task_work.c:180 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0xa2c/0x2650 kernel/exit.c:874 do_group_exit+0x206/0x2c0 kernel/exit.c:1024 get_signal+0x175d/0x1840 kernel/signal.c:2892 arch_do_signal_or_restart+0x96/0x860 arch/x86/kernel/signal.c:309 exit_to_user_mode_loop+0x6a/0x100 kernel/entry/common.c:168 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:204 __syscall_exit_to_user_mode_work kernel/entry/common.c:285 [inline] syscall_exit_to_user_mode+0x64/0x280 kernel/entry/common.c:296 do_syscall_64+0x4d/0xc0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x63/0xcd Memory state around the buggy address: ffff88806a407400: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806a407480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88806a407500: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88806a407580: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88806a407600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================