================================================================== BUG: KASAN: use-after-free in memcpy include/linux/string.h:406 [inline] BUG: KASAN: use-after-free in scr_memcpyw include/linux/vt_buffer.h:49 [inline] BUG: KASAN: use-after-free in vc_do_resize+0x9d6/0x13f0 drivers/tty/vt/vt.c:1286 Read of size 4 at addr ffff88809d8bc980 by task syz-executor.1/27688 CPU: 0 PID: 27688 Comm: syz-executor.1 Not tainted 5.8.0-rc7-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x18f/0x20d lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xae/0x436 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530 check_memory_region_inline mm/kasan/generic.c:186 [inline] check_memory_region+0x13d/0x180 mm/kasan/generic.c:192 memcpy+0x20/0x60 mm/kasan/common.c:105 memcpy include/linux/string.h:406 [inline] scr_memcpyw include/linux/vt_buffer.h:49 [inline] vc_do_resize+0x9d6/0x13f0 drivers/tty/vt/vt.c:1286 fbcon_modechanged+0x36c/0x710 drivers/video/fbdev/core/fbcon.c:2990 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3048 fb_set_var+0xae8/0xd60 drivers/video/fbdev/core/fbmem.c:1056 do_fb_ioctl+0x33f/0x6c0 drivers/video/fbdev/core/fbmem.c:1109 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1185 vfs_ioctl fs/ioctl.c:48 [inline] ksys_ioctl+0x11a/0x180 fs/ioctl.c:753 __do_sys_ioctl fs/ioctl.c:762 [inline] __se_sys_ioctl fs/ioctl.c:760 [inline] __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45c369 Code: 8d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 5b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f98eab83c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 000000000000d540 RCX: 000000000045c369 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003 RBP: 000000000078bfe0 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bfac R13: 0000000000c9fb6f R14: 00007f98eab849c0 R15: 000000000078bfac Allocated by task 27497: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc.constprop.0+0xc2/0xd0 mm/kasan/common.c:494 kmem_cache_alloc_trace+0x14f/0x2d0 mm/slab.c:3551 kmalloc include/linux/slab.h:555 [inline] kzalloc include/linux/slab.h:669 [inline] apparmor_sk_alloc_security+0x79/0xf0 security/apparmor/lsm.c:776 security_sk_alloc+0x50/0xb0 security/security.c:2180 sk_prot_alloc+0x24a/0x300 net/core/sock.c:1696 sk_alloc+0x32/0xbd0 net/core/sock.c:1747 __netlink_create+0x63/0x300 net/netlink/af_netlink.c:629 netlink_create+0x3a1/0x5d0 net/netlink/af_netlink.c:692 __sock_create+0x3ca/0x740 net/socket.c:1428 sock_create net/socket.c:1479 [inline] __sys_socket+0xef/0x200 net/socket.c:1521 __do_sys_socket net/socket.c:1530 [inline] __se_sys_socket net/socket.c:1528 [inline] __x64_sys_socket+0x6f/0xb0 net/socket.c:1528 do_syscall_64+0x60/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 458: save_stack+0x1b/0x40 mm/kasan/common.c:48 set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0xf5/0x140 mm/kasan/common.c:455 __cache_free mm/slab.c:3426 [inline] kfree+0x103/0x2c0 mm/slab.c:3757 security_sk_free+0x3e/0x70 security/security.c:2185 sk_prot_free net/core/sock.c:1726 [inline] __sk_destruct+0x537/0x860 net/core/sock.c:1815 sk_destruct+0xbd/0xe0 net/core/sock.c:1830 __sk_free+0xef/0x3d0 net/core/sock.c:1841 sk_free+0x78/0xa0 net/core/sock.c:1852 deferred_put_nlk_sk+0x151/0x2e0 net/netlink/af_netlink.c:729 rcu_do_batch kernel/rcu/tree.c:2414 [inline] rcu_core+0x5c7/0x1160 kernel/rcu/tree.c:2641 __do_softirq+0x34c/0xa60 kernel/softirq.c:292 The buggy address belongs to the object at ffff88809d8bc980 which belongs to the cache kmalloc-32 of size 32 The buggy address is located 0 bytes inside of 32-byte region [ffff88809d8bc980, ffff88809d8bc9a0) The buggy address belongs to the page: page:ffffea0002762f00 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88809d8bcfc1 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea0002a3d808 ffffea0002554dc8 ffff8880aa0001c0 raw: ffff88809d8bcfc1 ffff88809d8bc000 000000010000003e 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88809d8bc880: 00 00 fc fc fc fc fc fc 00 fc fc fc fc fc fc fc ffff88809d8bc900: 07 fc fc fc fc fc fc fc 07 fc fc fc fc fc fc fc >ffff88809d8bc980: fb fb fb fb fc fc fc fc 07 fc fc fc fc fc fc fc ^ ffff88809d8bca00: 00 07 fc fc fc fc fc fc 07 fc fc fc fc fc fc fc ffff88809d8bca80: 06 fc fc fc fc fc fc fc fb fb fb fb fc fc fc fc 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