KASAN: vmalloc-out-of-bounds Write in imageblit

Status: upstream: reported on 2026/08/06 13:30
Reported-by: syzbot+23839731b8735c36866b@syzkaller.appspotmail.com
First crash: 46d, last: 13h12m
▶ ▼ Similar bugs (10)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KASAN: vmalloc-out-of-bounds Write in imageblit fbdev 21 syz, C 104 1791d 2084d 20/29 fixed on 2021/11/10 00:50
upstream KASAN: vmalloc-out-of-bounds Write in imageblit (6) prio:high fbdev 21 syz, C 9767 7m 323d 0/29 upstream: reported C repro on 2025/11/02 21:10
linux-6.1 KASAN: vmalloc-out-of-bounds Write in imageblit origin:lts-only 21 syz, C 133 13h20m 46d 0/3 upstream: reported C repro on 2026/08/07 05:50
upstream KASAN: vmalloc-out-of-bounds Write in imageblit (5) fbdev 21 syz, C 1075 327d 378d 29/29 fixed on 2025/10/29 21:02
upstream KASAN: vmalloc-out-of-bounds Write in imageblit (4) fbdev 21 syz, C 3869 382d 761d 29/29 fixed on 2025/09/04 16:57
upstream KASAN: vmalloc-out-of-bounds Write in imageblit (3) fbdev 21 2 1154d 1150d 0/29 auto-obsoleted due to no activity on 2023/10/23 10:50
upstream KASAN: vmalloc-out-of-bounds Write in imageblit (2) fbdev 21 syz, C done 701 1480d 1767d 22/29 fixed on 2023/02/24 13:50
linux-6.6 KASAN: vmalloc-out-of-bounds Write in imageblit 21 42 13h19m 47d 0/2 upstream: reported on 2026/08/05 13:55
upstream KASAN: vmalloc-out-of-bounds Write in sys_imageblit fbdev 21 syz, C 91 2110d 2477d 0/29 auto-obsoleted due to no activity on 2022/12/09 01:09
upstream BUG: unable to handle kernel paging request in sys_imageblit fbdev 8 syz 16 2107d 2477d 0/29 auto-obsoleted due to no activity on 2022/08/31 01:46

Sample crash report:
==================================================================
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 ffffc90004b91be0 by task syz.3.2429/9781

CPU: 0 PID: 9781 Comm: syz.3.2429 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Call Trace:
 <TASK>
 dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106
 print_address_description+0x60/0x2d0 mm/kasan/report.c:248
 __kasan_report mm/kasan/report.c:434 [inline]
 kasan_report+0xdf/0x130 mm/kasan/report.c:451
 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:793
 soft_cursor+0x9fd/0xc30 drivers/video/fbdev/core/softcursor.c:74
 bit_cursor+0x16b5/0x1f40 drivers/video/fbdev/core/bitblit.c:409
 hide_cursor+0x7f/0x320 drivers/tty/vt/vt.c:907
 do_con_write+0x1dd/0x6c40 drivers/tty/vt/vt.c:2927
 con_put_char+0x7f/0xc0 drivers/tty/vt/vt.c:3303
 tty_put_char+0xc5/0x150 drivers/tty/tty_io.c:3178
 __process_echoes+0x1b1/0x8f0 drivers/tty/n_tty.c:743
 flush_echoes drivers/tty/n_tty.c:826 [inline]
 __receive_buf drivers/tty/n_tty.c:1579 [inline]
 n_tty_receive_buf_common+0x5edd/0x65b0 drivers/tty/n_tty.c:1674
 paste_selection+0x351/0x4e0 drivers/tty/vt/selection.c:408
 vt_ioctl+0x441/0x1ca0 drivers/tty/vt/vt_ioctl.c:764
 tty_ioctl+0x848/0xc30 drivers/tty/tty_io.c:2810
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:874 [inline]
 __se_sys_ioctl+0xfa/0x170 fs/ioctl.c:860
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7f55d6be4159
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:00007f55d4e3c028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f55d6e6bfa0 RCX: 00007f55d6be4159
RDX: 0000200000000000 RSI: 000000000000541c RDI: 0000000000000003
RBP: 00007f55d6c7b03b R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f55d6e6c038 R14: 00007f55d6e6bfa0 R15: 00007ffe581bb6b8
 </TASK>


Memory state around the buggy address:
 ffffc90004b91a80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
 ffffc90004b91b00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
>ffffc90004b91b80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
                                                       ^
 ffffc90004b91c00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
 ffffc90004b91c80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8
==================================================================

Crashes (46):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/09/14 15:41 linux-5.15.y 0248c33e835e 81a27d1a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/14 13:24 linux-5.15.y 0248c33e835e 70a60e12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/14 13:23 linux-5.15.y 0248c33e835e 70a60e12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/12 08:20 linux-5.15.y 0996e0926f6b 70a60e12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/12 08:19 linux-5.15.y 0996e0926f6b 70a60e12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/12 08:18 linux-5.15.y 0996e0926f6b 70a60e12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/12 06:52 linux-5.15.y 0996e0926f6b 70a60e12 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/11 16:23 linux-5.15.y 0996e0926f6b b6a5eeb7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/11 12:14 linux-5.15.y 0996e0926f6b b6a5eeb7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/11 12:14 linux-5.15.y 0996e0926f6b b6a5eeb7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/09 05:39 linux-5.15.y 0996e0926f6b 8387c273 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/09 05:39 linux-5.15.y 0996e0926f6b 8387c273 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/09 00:47 linux-5.15.y 0996e0926f6b 243b72f1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/08 10:54 linux-5.15.y 0996e0926f6b 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/08 10:53 linux-5.15.y 0996e0926f6b 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/07 18:34 linux-5.15.y 0996e0926f6b 680aa3e1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/04 02:09 linux-5.15.y 0996e0926f6b 801f0966 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/04 01:23 linux-5.15.y 0996e0926f6b 801f0966 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/04 01:22 linux-5.15.y 0996e0926f6b 801f0966 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/04 01:20 linux-5.15.y 0996e0926f6b 801f0966 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/04 01:19 linux-5.15.y 0996e0926f6b 801f0966 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/01 17:57 linux-5.15.y 28c35638ec51 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/01 17:57 linux-5.15.y 28c35638ec51 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/01 17:56 linux-5.15.y 28c35638ec51 587f6b29 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/29 21:32 linux-5.15.y 28c35638ec51 2f52988a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/26 18:16 linux-5.15.y 945fa863f02c a2b77b9e .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/26 05:34 linux-5.15.y 945fa863f02c 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/26 05:22 linux-5.15.y 945fa863f02c 6a91adb4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/19 22:43 linux-5.15.y 0eb903b5b519 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/15 02:31 linux-5.15.y aabd761612db 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/14 21:42 linux-5.15.y aabd761612db 6f9b3e89 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/14 16:09 linux-5.15.y aabd761612db 6f9b3e89 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/13 19:33 linux-5.15.y aabd761612db b13552fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/13 19:33 linux-5.15.y aabd761612db b13552fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/07 03:22 linux-5.15.y 9c7634c60784 c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/07 03:22 linux-5.15.y 9c7634c60784 c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/08/06 13:29 linux-5.15.y 6e2fd6534337 cd5b1963 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan KASAN: vmalloc-out-of-bounds Write in imageblit
2026/09/21 17:19 linux-5.15.y 0248c33e835e 853b104b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in imageblit
2026/09/16 00:36 linux-5.15.y 0248c33e835e 2daa4bb5 .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in imageblit
2026/09/10 13:53 linux-5.15.y 0996e0926f6b 1fe56c0a .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in imageblit
2026/08/23 22:11 linux-5.15.y 945fa863f02c 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in imageblit
2026/08/16 05:21 linux-5.15.y aabd761612db 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in imageblit
2026/08/15 23:03 linux-5.15.y aabd761612db 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in imageblit
2026/08/08 08:34 linux-5.15.y aabd761612db 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan BUG: unable to handle kernel paging request in imageblit
* Struck through repros no longer work on HEAD.