================================================================== 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+0x12f4/0x1430 drivers/video/fbdev/core/sysimgblt.c:275 Write of size 4 at addr ffffc9000b4f1fe0 by task syz-executor.1/22677 CPU: 0 PID: 22677 Comm: syz-executor.1 Not tainted 5.13.0-rc6-syzkaller #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:79 [inline] dump_stack+0x141/0x1d7 lib/dump_stack.c:120 print_address_description.constprop.0.cold+0x5/0x2f8 mm/kasan/report.c:233 __kasan_report mm/kasan/report.c:419 [inline] kasan_report.cold+0x7c/0xd8 mm/kasan/report.c:436 fast_imageblit drivers/video/fbdev/core/sysimgblt.c:229 [inline] sys_imageblit+0x12f4/0x1430 drivers/video/fbdev/core/sysimgblt.c:275 drm_fb_helper_sys_imageblit drivers/gpu/drm/drm_fb_helper.c:794 [inline] drm_fbdev_fb_imageblit+0x15c/0x350 drivers/gpu/drm/drm_fb_helper.c:2276 soft_cursor+0x514/0xa30 drivers/video/fbdev/core/softcursor.c:74 bit_cursor+0xd07/0x1740 drivers/video/fbdev/core/bitblit.c:377 fbcon_cursor+0x51d/0x630 drivers/video/fbdev/core/fbcon.c:1339 hide_cursor+0x85/0x280 drivers/tty/vt/vt.c:907 putconsxy+0x1d/0x450 drivers/tty/vt/vt.c:4732 vcs_write_buf drivers/tty/vt/vc_screen.c:535 [inline] vcs_write+0x9cf/0xb90 drivers/tty/vt/vc_screen.c:680 do_loop_readv_writev fs/read_write.c:764 [inline] do_loop_readv_writev fs/read_write.c:748 [inline] do_iter_write+0x489/0x670 fs/read_write.c:868 vfs_writev+0x1aa/0x630 fs/read_write.c:939 do_pwritev+0x1bc/0x270 fs/read_write.c:1036 do_syscall_32_irqs_on arch/x86/entry/common.c:78 [inline] __do_fast_syscall_32+0x67/0xe0 arch/x86/entry/common.c:143 do_fast_syscall_32+0x2f/0x70 arch/x86/entry/common.c:168 entry_SYSENTER_compat_after_hwframe+0x4d/0x5c RIP: 0023:0xf7ffa549 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:00000000f55f45fc EFLAGS: 00000296 ORIG_RAX: 000000000000014e RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 0000000020000640 RDX: 0000000000000003 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Memory state around the buggy address: ffffc9000b4f1e80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ffffc9000b4f1f00: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 >ffffc9000b4f1f80: f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 f8 ^ ffffc9000b4f2000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ffffc9000b4f2080: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ==================================================================