loop5: detected capacity change from 0 to 128 EXT4-fs (loop5): mounted filesystem without journal. Quota mode: writeback. ext4 filesystem being mounted at /111/file1 supports timestamps until 2038-01-19 (0x7fffffff) ================================================================== BUG: KASAN: vmalloc-out-of-bounds in fast_imageblit drivers/video/fbdev/core/sysimgblt.c:257 [inline] BUG: KASAN: vmalloc-out-of-bounds in sys_imageblit+0x1ba8/0x25d0 drivers/video/fbdev/core/sysimgblt.c:323 Write of size 4 at addr ffffc900043c9fe0 by task syz.5.1243/10358 CPU: 0 PID: 10358 Comm: syz.5.1243 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 Call Trace: dump_stack_lvl+0x188/0x24e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 fast_imageblit drivers/video/fbdev/core/sysimgblt.c:257 [inline] sys_imageblit+0x1ba8/0x25d0 drivers/video/fbdev/core/sysimgblt.c:323 drm_fb_helper_sys_imageblit+0x2e/0x510 drivers/gpu/drm/drm_fb_helper.c:864 cw_putcs_aligned drivers/video/fbdev/core/fbcon_cw.c:110 [inline] cw_putcs+0x15ef/0x18a0 drivers/video/fbdev/core/fbcon_cw.c:158 fbcon_putcs+0x358/0x510 drivers/video/fbdev/core/fbcon.c:1300 do_update_region+0x4e5/0x640 drivers/tty/vt/vt.c:676 redraw_screen+0xa2c/0x1000 drivers/tty/vt/vt.c:1035 vc_do_resize+0x122c/0x17b0 drivers/tty/vt/vt.c:1342 fbcon_do_set_font+0xb5c/0x1ae0 drivers/video/fbdev/core/fbcon.c:2446 con_font_set drivers/tty/vt/vt.c:4678 [inline] con_font_op+0xac1/0xdb0 drivers/tty/vt/vt.c:4724 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline] vt_ioctl+0x1635/0x1cc0 drivers/tty/vt/vt_ioctl.c:752 tty_ioctl+0x7e6/0xba0 drivers/tty/tty_io.c:2776 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:870 [inline] __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:856 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f10fd19e0d9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 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 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f10fe02b028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 00007f10fd425fa0 RCX: 00007f10fd19e0d9 RDX: 00002000000001c0 RSI: 0000000000004b72 RDI: 000000000000000a RBP: 00007f10fd235024 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f10fd426038 R14: 00007f10fd425fa0 R15: 00007ffec69f2268 The buggy address belongs to a 2-page vmalloc region starting at 0xffffc900043ca000 allocated at kcov_ioctl+0x54/0x610 kernel/kcov.c:713 Memory state around the buggy address: ffffc900043c9e80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffffc900043c9f00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 >ffffc900043c9f80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ^ ffffc900043ca000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc900043ca080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================