================================================================== 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+0x1ed0/0x2240 drivers/video/fbdev/core/sysimgblt.c:323 Write of size 4 at addr ffffc900046c1000 by task syz-executor.1/21734 CPU: 3 PID: 21734 Comm: syz-executor.1 Not tainted 5.19.0-rc6-syzkaller-00111-gb047602d579b #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.14.0-2 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/0x495 mm/kasan/report.c:313 print_report mm/kasan/report.c:429 [inline] kasan_report.cold+0xf4/0x1c6 mm/kasan/report.c:491 fast_imageblit drivers/video/fbdev/core/sysimgblt.c:257 [inline] sys_imageblit+0x1ed0/0x2240 drivers/video/fbdev/core/sysimgblt.c:323 drm_fb_helper_sys_imageblit drivers/gpu/drm/drm_fb_helper.c:825 [inline] drm_fbdev_fb_imageblit+0x15c/0x350 drivers/gpu/drm/drm_fb_helper.c:2328 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:139 [inline] bit_putcs+0x6e1/0xd20 drivers/video/fbdev/core/bitblit.c:188 fbcon_putcs+0x314/0x3e0 drivers/video/fbdev/core/fbcon.c:1285 do_update_region+0x399/0x630 drivers/tty/vt/vt.c:676 invert_screen+0x1d4/0x600 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+0xe61/0x1170 drivers/tty/vt/vt.c:1257 fbcon_do_set_font+0x43a/0x6f0 drivers/video/fbdev/core/fbcon.c:2431 fbcon_set_font+0x89d/0xab0 drivers/video/fbdev/core/fbcon.c:2522 con_font_set drivers/tty/vt/vt.c:4666 [inline] con_font_op+0x73a/0xc90 drivers/tty/vt/vt.c:4710 compat_kdfontop_ioctl drivers/tty/vt/vt_ioctl.c:1022 [inline] vt_compat_ioctl+0x2d7/0x450 drivers/tty/vt/vt_ioctl.c:1081 tty_compat_ioctl+0x19b/0x3f0 drivers/tty/tty_io.c:2957 __do_compat_sys_ioctl+0x1c7/0x290 fs/ioctl.c:968 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x65/0xf0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7fd7549 Code: 03 74 c0 01 10 05 03 74 b8 01 10 06 03 74 b4 01 10 07 03 74 b0 01 10 08 03 74 d8 01 00 00 00 00 00 51 52 55 89 e5 0f 34 cd 80 <5d> 5a 59 c3 90 90 90 90 8d b4 26 00 00 00 00 8d b4 26 00 00 00 00 RSP: 002b:00000000f7fd25cc EFLAGS: 00000296 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000004b72 RDX: 0000000020000180 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000296 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 The buggy address belongs to the virtual mapping at [ffffc900043c1000, ffffc900046c2000) created by: drm_fb_helper_generic_probe+0x4de/0x930 drivers/gpu/drm/drm_fb_helper.c:2394 Memory state around the buggy address: ffffc900046c0f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc900046c0f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc900046c1000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ^ ffffc900046c1080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffffc900046c1100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ================================================================== ---------------- Code disassembly (best guess): 0: 03 74 c0 01 add 0x1(%rax,%rax,8),%esi 4: 10 05 03 74 b8 01 adc %al,0x1b87403(%rip) # 0x1b8740d a: 10 06 adc %al,(%rsi) c: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 10: 10 07 adc %al,(%rdi) 12: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi 16: 10 08 adc %cl,(%rax) 18: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1c: 00 00 add %al,(%rax) 1e: 00 00 add %al,(%rax) 20: 00 51 52 add %dl,0x52(%rcx) 23: 55 push %rbp 24: 89 e5 mov %esp,%ebp 26: 0f 34 sysenter 28: cd 80 int $0x80 * 2a: 5d pop %rbp <-- trapping instruction 2b: 5a pop %rdx 2c: 59 pop %rcx 2d: c3 retq 2e: 90 nop 2f: 90 nop 30: 90 nop 31: 90 nop 32: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 39: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi