BUG: unable to handle page fault for address: ffff888001000050 #PF: supervisor write access in kernel mode #PF: error_code(0x0003) - permissions violation PGD 10601067 P4D 10601067 PUD 10602067 PMD 80000000010001e1 Oops: 0003 [#1] PREEMPT SMP KASAN CPU: 1 PID: 8458 Comm: syz-executor826 Not tainted 5.14.0-rc6-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:writeb arch/x86/include/asm/io.h:65 [inline] RIP: 0010:vga16fb_fillrect+0x993/0x18d0 drivers/video/fbdev/vga16fb.c:923 Code: 68 fd 48 63 44 24 10 45 31 f6 48 89 04 24 e8 04 69 68 fd 31 ff 89 de 31 ed e8 39 70 68 fd 85 db 4d 89 ec 74 22 e8 ed 68 68 fd <45> 88 34 24 83 c5 01 89 df 49 83 c4 01 89 ee e8 09 71 68 fd 39 eb RSP: 0018:ffffc9000172f848 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 000000000000001b RCX: 0000000000000000 RDX: ffff88802cf6d4c0 RSI: ffffffff840d4013 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff840d399d R10: ffffffff840d4007 R11: 0000000000000000 R12: ffff888001000050 R13: ffff888001000050 R14: 0000000000000000 R15: 000000000ffeb7ff FS: 0000000000b04300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff888001000050 CR3: 0000000020439000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: bit_clear_margins+0x3f6/0x4b0 drivers/video/fbdev/core/bitblit.c:224 fbcon_clear_margins+0x1f1/0x280 drivers/video/fbdev/core/fbcon.c:1315 fbcon_switch+0xa8c/0x1620 drivers/video/fbdev/core/fbcon.c:2146 redraw_screen+0x2b9/0x740 drivers/tty/vt/vt.c:1021 fbcon_modechanged+0x593/0x6d0 drivers/video/fbdev/core/fbcon.c:2651 fbcon_update_vcs+0x3a/0x50 drivers/video/fbdev/core/fbcon.c:2696 do_fb_ioctl+0x62e/0x690 drivers/video/fbdev/core/fbmem.c:1108 fb_ioctl+0xe7/0x150 drivers/video/fbdev/core/fbmem.c:1183 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:1069 [inline] __se_sys_ioctl fs/ioctl.c:1055 [inline] __x64_sys_ioctl+0x193/0x200 fs/ioctl.c:1055 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x43efd9 Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 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 c0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fff35bd6098 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000400488 RCX: 000000000043efd9 RDX: 0000000020000200 RSI: 0000000000004601 RDI: 0000000000000003 RBP: 0000000000402fc0 R08: 0000000000000000 R09: 0000000000400488 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000403050 R13: 0000000000000000 R14: 00000000004ac018 R15: 0000000000400488 Modules linked in: CR2: ffff888001000050 ---[ end trace e56988c1407c1ce2 ]--- RIP: 0010:writeb arch/x86/include/asm/io.h:65 [inline] RIP: 0010:vga16fb_fillrect+0x993/0x18d0 drivers/video/fbdev/vga16fb.c:923 Code: 68 fd 48 63 44 24 10 45 31 f6 48 89 04 24 e8 04 69 68 fd 31 ff 89 de 31 ed e8 39 70 68 fd 85 db 4d 89 ec 74 22 e8 ed 68 68 fd <45> 88 34 24 83 c5 01 89 df 49 83 c4 01 89 ee e8 09 71 68 fd 39 eb RSP: 0018:ffffc9000172f848 EFLAGS: 00010293 RAX: 0000000000000000 RBX: 000000000000001b RCX: 0000000000000000 RDX: ffff88802cf6d4c0 RSI: ffffffff840d4013 RDI: 0000000000000003 RBP: 0000000000000000 R08: 0000000000000000 R09: ffffffff840d399d R10: ffffffff840d4007 R11: 0000000000000000 R12: ffff888001000050 R13: ffff888001000050 R14: 0000000000000000 R15: 000000000ffeb7ff FS: 0000000000b04300(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff888001000050 CR3: 0000000020439000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 68 fd 48 63 44 pushq $0x446348fd 5: 24 10 and $0x10,%al 7: 45 31 f6 xor %r14d,%r14d a: 48 89 04 24 mov %rax,(%rsp) e: e8 04 69 68 fd callq 0xfd686917 13: 31 ff xor %edi,%edi 15: 89 de mov %ebx,%esi 17: 31 ed xor %ebp,%ebp 19: e8 39 70 68 fd callq 0xfd687057 1e: 85 db test %ebx,%ebx 20: 4d 89 ec mov %r13,%r12 23: 74 22 je 0x47 25: e8 ed 68 68 fd callq 0xfd686917 * 2a: 45 88 34 24 mov %r14b,(%r12) <-- trapping instruction 2e: 83 c5 01 add $0x1,%ebp 31: 89 df mov %ebx,%edi 33: 49 83 c4 01 add $0x1,%r12 37: 89 ee mov %ebp,%esi 39: e8 09 71 68 fd callq 0xfd687147 3e: 39 eb cmp %ebp,%ebx