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BUG: KASAN: vmalloc-out-of-bounds in bitfill_aligned drivers/video/fbdev/core/sysfillrect.c:54 [inline]
BUG: KASAN: vmalloc-out-of-bounds in bitfill_aligned+0x34b/0x410 drivers/video/fbdev/core/sysfillrect.c:25
Write of size 8 at addr ffffc9000a321000 by task syz-executor726/8478

CPU: 0 PID: 8478 Comm: syz-executor726 Not tainted 5.7.0-syzkaller #0
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS rel-1.12.0-59-gc9ba5276e321-prebuilt.qemu.org 04/01/2014
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x188/0x20d lib/dump_stack.c:118
 print_address_description.constprop.0.cold+0x5/0x413 mm/kasan/report.c:383
 __kasan_report mm/kasan/report.c:513 [inline]
 kasan_report.cold+0x1f/0x37 mm/kasan/report.c:530
 bitfill_aligned drivers/video/fbdev/core/sysfillrect.c:54 [inline]
 bitfill_aligned+0x34b/0x410 drivers/video/fbdev/core/sysfillrect.c:25
 sys_fillrect+0x415/0x7a0 drivers/video/fbdev/core/sysfillrect.c:291
 drm_fb_helper_sys_fillrect+0x1c/0x190 drivers/gpu/drm/drm_fb_helper.c:715
 bit_clear_margins+0x3f6/0x4a0 drivers/video/fbdev/core/bitblit.c:224
 fbcon_clear_margins+0x1de/0x240 drivers/video/fbdev/core/fbcon.c:1381
 fbcon_switch+0xcde/0x16f0 drivers/video/fbdev/core/fbcon.c:2363
 redraw_screen+0x2ae/0x770 drivers/tty/vt/vt.c:1015
 fbcon_modechanged+0x581/0x720 drivers/video/fbdev/core/fbcon.c:3000
 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:3047
 fb_set_var+0xb03/0xd90 drivers/video/fbdev/core/fbmem.c:1056
 do_fb_ioctl+0x390/0x6e0 drivers/video/fbdev/core/fbmem.c:1109
 fb_compat_ioctl+0x305/0xc50 drivers/video/fbdev/core/fbmem.c:1315
 __do_compat_sys_ioctl fs/ioctl.c:865 [inline]
 __se_compat_sys_ioctl fs/ioctl.c:816 [inline]
 __ia32_compat_sys_ioctl+0x23d/0x2b0 fs/ioctl.c:816
 do_syscall_32_irqs_on arch/x86/entry/common.c:337 [inline]
 do_fast_syscall_32+0x270/0xe90 arch/x86/entry/common.c:396
 entry_SYSENTER_compat+0x70/0x7f arch/x86/entry/entry_64_compat.S:139


Memory state around the buggy address:
 ffffc9000a320f00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
 ffffc9000a320f80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
>ffffc9000a321000: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
                   ^
 ffffc9000a321080: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
 ffffc9000a321100: f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9 f9
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