vc->vc_screenbuf=ffff8880a89bf800 old_screen_size=640 old_row_size=320 old_rows=2 old_cols=160 new_screen_size=384 new_row_size=192 new_rows=2 new_cols=96 vc->vc_screenbuf=ffff88808f81f800 old_screen_size=640 old_row_size=320 old_rows=2 old_cols=160 new_screen_size=384 new_row_size=192 new_rows=2 new_cols=96 ================================================================== 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+0xf3f/0x1e90 drivers/tty/vt/vt.c:1290 Read of size 192 at addr ffff88808f81f940 by task syz-executor.3/11762 CPU: 0 PID: 11762 Comm: syz-executor.3 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+0x202/0x328 lib/dump_stack.c:118 print_address_description+0x66/0x5a0 mm/kasan/report.c:383 __kasan_report mm/kasan/report.c:513 [inline] kasan_report+0x134/0x1d0 mm/kasan/report.c:530 check_memory_region_inline mm/kasan/generic.c:183 [inline] check_memory_region+0x2b6/0x2f0 mm/kasan/generic.c:192 memcpy+0x2d/0x70 mm/kasan/common.c:105 scr_memcpyw include/linux/vt_buffer.h:49 [inline] vc_do_resize+0xf3f/0x1e90 drivers/tty/vt/vt.c:1290 vc_resize+0x4f/0x60 drivers/tty/vt/vt.c:1344 fbcon_modechanged+0x704/0xdf0 drivers/video/fbdev/core/fbcon.c:2990 fbcon_update_vcs+0x31/0x40 drivers/video/fbdev/core/fbcon.c:3048 fb_set_var+0x8f8/0xdc0 drivers/video/fbdev/core/fbmem.c:1056 do_fb_ioctl+0x55e/0x780 drivers/video/fbdev/core/fbmem.c:1109 fb_ioctl+0xb9/0xf0 drivers/video/fbdev/core/fbmem.c:1185 vfs_ioctl fs/ioctl.c:48 [inline] ksys_ioctl fs/ioctl.c:753 [inline] __do_sys_ioctl fs/ioctl.c:762 [inline] __se_sys_ioctl+0x113/0x190 fs/ioctl.c:760 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:760 do_syscall_64+0x76/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x45b3c9 Code: 2d 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 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00 RSP: 002b:00007fa453176c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007fa4531776d4 RCX: 000000000045b3c9 RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000004 RBP: 000000000075c070 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00000000ffffffff R13: 00000000000002cd R14: 00000000004c3e46 R15: 000000000075c07c Allocated by task 11762: save_stack mm/kasan/common.c:48 [inline] set_track mm/kasan/common.c:56 [inline] __kasan_kmalloc+0x103/0x140 mm/kasan/common.c:494 kasan_kmalloc+0x9/0x10 mm/kasan/common.c:508 __do_kmalloc mm/slab.c:3656 [inline] __kmalloc+0x254/0x340 mm/slab.c:3665 kmalloc include/linux/slab.h:560 [inline] kzalloc+0x21/0x40 include/linux/slab.h:669 vc_do_resize+0x2c0/0x1e90 drivers/tty/vt/vt.c:1223 vc_resize+0x4f/0x60 drivers/tty/vt/vt.c:1344 fbcon_modechanged+0x704/0xdf0 drivers/video/fbdev/core/fbcon.c:2990 fbcon_update_vcs+0x31/0x40 drivers/video/fbdev/core/fbcon.c:3048 fb_set_var+0x8f8/0xdc0 drivers/video/fbdev/core/fbmem.c:1056 fbcon_resize+0x819/0x11f0 drivers/video/fbdev/core/fbcon.c:2231 resize_screen drivers/tty/vt/vt.c:1170 [inline] vc_do_resize+0x798/0x1e90 drivers/tty/vt/vt.c:1243 vc_resize+0x4f/0x60 drivers/tty/vt/vt.c:1344 fbcon_modechanged+0x704/0xdf0 drivers/video/fbdev/core/fbcon.c:2990 fbcon_update_vcs+0x31/0x40 drivers/video/fbdev/core/fbcon.c:3048 fb_set_var+0x8f8/0xdc0 drivers/video/fbdev/core/fbmem.c:1056 do_fb_ioctl+0x55e/0x780 drivers/video/fbdev/core/fbmem.c:1109 fb_ioctl+0xb9/0xf0 drivers/video/fbdev/core/fbmem.c:1185 vfs_ioctl fs/ioctl.c:48 [inline] ksys_ioctl fs/ioctl.c:753 [inline] __do_sys_ioctl fs/ioctl.c:762 [inline] __se_sys_ioctl+0x113/0x190 fs/ioctl.c:760 __x64_sys_ioctl+0x7b/0x90 fs/ioctl.c:760 do_syscall_64+0x76/0xe0 arch/x86/entry/common.c:384 entry_SYSCALL_64_after_hwframe+0x44/0xa9 Freed by task 11396: save_stack mm/kasan/common.c:48 [inline] set_track mm/kasan/common.c:56 [inline] kasan_set_free_info mm/kasan/common.c:316 [inline] __kasan_slab_free+0x114/0x170 mm/kasan/common.c:455 kasan_slab_free+0xe/0x10 mm/kasan/common.c:464 __cache_free mm/slab.c:3426 [inline] kfree+0x10d/0x220 mm/slab.c:3757 free_bprm+0x19f/0x1b0 fs/exec.c:1560 __do_execve_file+0xda1/0x2310 fs/exec.c:1963 do_execveat_common fs/exec.c:1980 [inline] do_execve+0x33/0x40 fs/exec.c:1997 call_usermodehelper_exec_async+0x31b/0x4d0 kernel/umh.c:112 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88808f81f800 which belongs to the cache kmalloc-512 of size 512 The buggy address is located 320 bytes inside of 512-byte region [ffff88808f81f800, ffff88808f81fa00) The buggy address belongs to the page: page:ffffea00023e07c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 flags: 0xfffe0000000200(slab) raw: 00fffe0000000200 ffffea000277a708 ffffea00028348c8 ffff8880aa400a80 raw: 0000000000000000 ffff88808f81f000 0000000100000004 0000000000000000 page dumped because: kasan: bad access detected Memory state around the buggy address: ffff88808f81f880: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffff88808f81f900: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffff88808f81f980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ^ ffff88808f81fa00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88808f81fa80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================