================================================================== BUG: KASAN: slab-out-of-bounds in memcpy include/linux/string.h:381 [inline] BUG: KASAN: slab-out-of-bounds in scr_memcpyw include/linux/vt_buffer.h:49 [inline] BUG: KASAN: slab-out-of-bounds in vc_do_resize+0x959/0x1460 drivers/tty/vt/vt.c:1250 Read of size 4 at addr ffff88808360b600 by task syz-executor.0/25268 CPU: 1 PID: 25268 Comm: syz-executor.0 Not tainted 5.6.0-rc2-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+0x197/0x210 lib/dump_stack.c:118 print_address_description.constprop.0.cold+0xd4/0x30b mm/kasan/report.c:374 __kasan_report.cold+0x1b/0x32 mm/kasan/report.c:506 kasan_report+0x12/0x20 mm/kasan/common.c:641 check_memory_region_inline mm/kasan/generic.c:185 [inline] check_memory_region+0x134/0x1a0 mm/kasan/generic.c:192 memcpy+0x24/0x50 mm/kasan/common.c:127 memcpy include/linux/string.h:381 [inline] scr_memcpyw include/linux/vt_buffer.h:49 [inline] vc_do_resize+0x959/0x1460 drivers/tty/vt/vt.c:1250 vc_resize+0x4d/0x60 drivers/tty/vt/vt.c:1304 fbcon_modechanged+0x367/0x790 drivers/video/fbdev/core/fbcon.c:2987 fbcon_update_vcs+0x42/0x50 drivers/video/fbdev/core/fbcon.c:3045 fb_set_var+0xb32/0xdd0 drivers/video/fbdev/core/fbmem.c:1056 do_fb_ioctl+0x390/0x7d0 drivers/video/fbdev/core/fbmem.c:1109 fb_ioctl+0xe6/0x130 drivers/video/fbdev/core/fbmem.c:1185 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe RIP: 0033:0x45c449 Code: ad 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 7b b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007f79d6cf4c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f79d6cf56d4 RCX: 000000000045c449 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000004 RBP: 000000000076bf20 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000002ef R14: 00000000004c5076 R15: 000000000076bf2c Allocated by task 25268: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] __kasan_kmalloc mm/kasan/common.c:515 [inline] __kasan_kmalloc.constprop.0+0xcf/0xe0 mm/kasan/common.c:488 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:529 __do_kmalloc mm/slab.c:3656 [inline] __kmalloc+0x163/0x770 mm/slab.c:3665 kmalloc include/linux/slab.h:560 [inline] kzalloc include/linux/slab.h:669 [inline] vc_do_resize+0x262/0x1460 drivers/tty/vt/vt.c:1187 vc_resize+0x4d/0x60 drivers/tty/vt/vt.c:1304 fbcon_modechanged+0x367/0x790 drivers/video/fbdev/core/fbcon.c:2987 fbcon_update_vcs+0x42/0x50 drivers/video/fbdev/core/fbcon.c:3045 fb_set_var+0xb32/0xdd0 drivers/video/fbdev/core/fbmem.c:1056 fbcon_resize+0x6b1/0x780 drivers/video/fbdev/core/fbcon.c:2229 resize_screen drivers/tty/vt/vt.c:1126 [inline] vc_do_resize+0x440/0x1460 drivers/tty/vt/vt.c:1205 vc_resize+0x4d/0x60 drivers/tty/vt/vt.c:1304 fbcon_modechanged+0x367/0x790 drivers/video/fbdev/core/fbcon.c:2987 fbcon_update_vcs+0x42/0x50 drivers/video/fbdev/core/fbcon.c:3045 fb_set_var+0xb32/0xdd0 drivers/video/fbdev/core/fbmem.c:1056 do_fb_ioctl+0x390/0x7d0 drivers/video/fbdev/core/fbmem.c:1109 fb_ioctl+0xe6/0x130 drivers/video/fbdev/core/fbmem.c:1185 vfs_ioctl fs/ioctl.c:47 [inline] ksys_ioctl+0x123/0x180 fs/ioctl.c:763 __do_sys_ioctl fs/ioctl.c:772 [inline] __se_sys_ioctl fs/ioctl.c:770 [inline] __x64_sys_ioctl+0x73/0xb0 fs/ioctl.c:770 do_syscall_64+0xfa/0x790 arch/x86/entry/common.c:294 entry_SYSCALL_64_after_hwframe+0x49/0xbe Freed by task 16: save_stack+0x23/0x90 mm/kasan/common.c:72 set_track mm/kasan/common.c:80 [inline] kasan_set_free_info mm/kasan/common.c:337 [inline] __kasan_slab_free+0x102/0x150 mm/kasan/common.c:476 kasan_slab_free+0xe/0x10 mm/kasan/common.c:485 __cache_free mm/slab.c:3426 [inline] kfree+0x10a/0x2c0 mm/slab.c:3757 free_event_rcu+0x5e/0x70 kernel/events/core.c:4373 rcu_do_batch kernel/rcu/tree.c:2186 [inline] rcu_core+0x5e1/0x1390 kernel/rcu/tree.c:2410 rcu_core_si+0x9/0x10 kernel/rcu/tree.c:2419 __do_softirq+0x262/0x98c kernel/softirq.c:292 The buggy address belongs to the object at ffff88808360b000 which belongs to the cache kmalloc-2k of size 2048 The buggy address is located 1536 bytes inside of 2048-byte region [ffff88808360b000, ffff88808360b800) The buggy address belongs to the page: page:ffffea00020d82c0 refcount:1 mapcount:0 mapping:ffff8880aa400e00 index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea000238cc08 ffffea0002a29808 ffff8880aa400e00 raw: 0000000000000000 ffff88808360b000 0000000100000001 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808360b500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88808360b580: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88808360b600: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88808360b680: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808360b700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================