Hi, This bug can still be triggered repeatedly on the latest Linux. HEAD commit: 519d81956ee2 Linux 5.15-rc6 git tree: upstream console output: https://drive.google.com/file/d/17xFIX8JgBxamy8iUnUTAdcVvaASuhqxr/view?usp=sharing kernel config: https://drive.google.com/file/d/12PUnxIM1EPBgW4ZJmI7WJBRaY1lA83an/view?usp=sharing ================================================================== BUG: KASAN: vmalloc-out-of-bounds in fast_imageblit drivers/video/fbdev/core/sysimgblt.c:229 [inline] BUG: KASAN: vmalloc-out-of-bounds in sys_imageblit+0x1372/0x13f0 drivers/video/fbdev/core/sysimgblt.c:275 Write of size 4 at addr ffffc90005759380 by task syz-executor/31261 CPU: 2 PID: 31261 Comm: syz-executor Not tainted 5.15.0-rc6 #4 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0xf/0x334 mm/kasan/report.c:256 __kasan_report mm/kasan/report.c:442 [inline] kasan_report.cold+0x83/0xdf mm/kasan/report.c:459 fast_imageblit drivers/video/fbdev/core/sysimgblt.c:229 [inline] sys_imageblit+0x1372/0x13f0 drivers/video/fbdev/core/sysimgblt.c:275 drm_fb_helper_sys_imageblit+0x1c/0x180 drivers/gpu/drm/drm_fb_helper.c:794 drm_fbdev_fb_imageblit+0x179/0x260 drivers/gpu/drm/drm_fb_helper.c:2282 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:139 [inline] bit_putcs+0x8ed/0xd80 drivers/video/fbdev/core/bitblit.c:188 fbcon_putcs+0x362/0x450 drivers/video/fbdev/core/fbcon.c:1296 do_update_region+0x399/0x630 drivers/tty/vt/vt.c:676 invert_screen+0x2a7/0x610 drivers/tty/vt/vt.c:800 highlight drivers/tty/vt/selection.c:57 [inline] clear_selection drivers/tty/vt/selection.c:84 [inline] clear_selection+0x55/0x70 drivers/tty/vt/selection.c:80 vc_do_resize+0xda8/0x10a0 drivers/tty/vt/vt.c:1257 fbcon_do_set_font+0x47e/0x780 drivers/video/fbdev/core/fbcon.c:2397 fbcon_set_font+0x81e/0xa10 drivers/video/fbdev/core/fbcon.c:2483 con_font_set drivers/tty/vt/vt.c:4666 [inline] con_font_op+0x73a/0xca0 drivers/tty/vt/vt.c:4710 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline] vt_ioctl+0x1de9/0x2af0 drivers/tty/vt/vt_ioctl.c:752 tty_ioctl+0xc80/0x1450 drivers/tty/tty_io.c:2805 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl fs/ioctl.c:860 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7ff832e3ec4d Code: 02 b8 ff ff ff ff c3 66 0f 1f 44 00 00 f3 0f 1e fa 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 bc ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ff8303a6c58 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007ff832f650a0 RCX: 00007ff832e3ec4d RDX: 0000000020000100 RSI: 0000000000004b72 RDI: 0000000000000004 RBP: 00007ff832eb7d80 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 00007ff832f650a0 R13: 00007ffffdbaddff R14: 00007ffffdbadfa0 R15: 00007ff8303a6dc0 Memory state around the buggy address: ffffc90005759280: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffffc90005759300: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 >ffffc90005759380: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ^ ffffc90005759400: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffffc90005759480: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ==================================================================