================================================================== 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+0x1fd4/0x20e0 drivers/video/fbdev/core/sysimgblt.c:323 Write of size 4 at addr ffffc90004819000 by task syz-executor.0/10929 CPU: 1 PID: 10929 Comm: syz-executor.0 Not tainted 6.5.0-rc3-syzkaller-00018-g0b5547c51827 #0 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014 Call Trace: __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xc4/0x620 mm/kasan/report.c:475 kasan_report+0xda/0x110 mm/kasan/report.c:588 fast_imageblit drivers/video/fbdev/core/sysimgblt.c:257 [inline] sys_imageblit+0x1fd4/0x20e0 drivers/video/fbdev/core/sysimgblt.c:323 drm_fbdev_generic_defio_imageblit+0x20/0x130 drivers/gpu/drm/drm_fbdev_generic.c:37 bit_putcs_unaligned drivers/video/fbdev/core/bitblit.c:139 [inline] bit_putcs+0x90b/0xde0 drivers/video/fbdev/core/bitblit.c:188 fbcon_putcs+0x314/0x3d0 drivers/video/fbdev/core/fbcon.c:1281 do_update_region+0x3e0/0x670 drivers/tty/vt/vt.c:624 invert_screen+0x1dd/0x620 drivers/tty/vt/vt.c:749 highlight drivers/tty/vt/selection.c:57 [inline] clear_selection drivers/tty/vt/selection.c:85 [inline] clear_selection+0x59/0x70 drivers/tty/vt/selection.c:81 vc_do_resize+0xeb6/0x11d0 drivers/tty/vt/vt.c:1207 fbcon_set_disp+0x7a3/0xe00 drivers/video/fbdev/core/fbcon.c:1390 con2fb_init_display drivers/video/fbdev/core/fbcon.c:793 [inline] set_con2fb_map+0x6fb/0x1050 drivers/video/fbdev/core/fbcon.c:864 fbcon_set_con2fb_map_ioctl+0x16d/0x220 drivers/video/fbdev/core/fbcon.c:3122 do_fb_ioctl+0x326/0x7d0 drivers/video/fbdev/core/fbmem.c:1068 fb_compat_ioctl+0x568/0x670 drivers/video/fbdev/core/fbmem.c:1223 __do_compat_sys_ioctl+0x2bf/0x330 fs/ioctl.c:968 do_syscall_32_irqs_on arch/x86/entry/common.c:112 [inline] __do_fast_syscall_32+0x61/0xe0 arch/x86/entry/common.c:178 do_fast_syscall_32+0x33/0x70 arch/x86/entry/common.c:203 entry_SYSENTER_compat_after_hwframe+0x70/0x82 RIP: 0023:0xf7f49579 Code: 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 00 00 00 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:00000000f7f445ac EFLAGS: 00000292 ORIG_RAX: 0000000000000036 RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000000004610 RDX: 00000000200001c0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000292 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 The buggy address belongs to the virtual mapping at [ffffc90004519000, ffffc9000481a000) created by: drm_fbdev_generic_helper_fb_probe+0x300/0x6d0 drivers/gpu/drm/drm_fbdev_generic.c:97 Memory state around the buggy address: ffffc90004818f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc90004818f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 >ffffc90004819000: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ^ ffffc90004819080: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffffc90004819100: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ================================================================== ---------------- Code disassembly (best guess), 2 bytes skipped: 0: 10 06 adc %al,(%rsi) 2: 03 74 b4 01 add 0x1(%rsp,%rsi,4),%esi 6: 10 07 adc %al,(%rdi) 8: 03 74 b0 01 add 0x1(%rax,%rsi,4),%esi c: 10 08 adc %cl,(%rax) e: 03 74 d8 01 add 0x1(%rax,%rbx,8),%esi 1e: 00 51 52 add %dl,0x52(%rcx) 21: 55 push %rbp 22: 89 e5 mov %esp,%ebp 24: 0f 34 sysenter 26: cd 80 int $0x80 * 28: 5d pop %rbp <-- trapping instruction 29: 5a pop %rdx 2a: 59 pop %rcx 2b: c3 ret 2c: 90 nop 2d: 90 nop 2e: 90 nop 2f: 90 nop 30: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi 37: 8d b4 26 00 00 00 00 lea 0x0(%rsi,%riz,1),%esi