syzbot has found a reproducer for the following issue on:
HEAD commit: 2a987e65025e Merge tag 'perf-tools-fixes-for-v5.16-2021-12.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=12f8fdc5b00000 kernel config: https://syzkaller.appspot.com/x/.config?x=7d5e878e3399b6cc dashboard link: https://syzkaller.appspot.com/bug?extid=a4edd73d589b0b7efbeb compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.2 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=16671badb00000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=122beabdb00000
IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+a4edd73d589b0b7efbeb@syzkaller.appspotmail.com
BUG: unable to handle page fault for address: ffff888001000030 #PF: supervisor write access in kernel mode #PF: error_code(0x0003) - permissions violation PGD 11201067 P4D 11201067 PUD 11202067 PMD 80000000010001e1 Oops: 0003 [#1] PREEMPT SMP KASAN CPU: 0 PID: 6524 Comm: syz-executor260 Not tainted 5.16.0-rc4-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:__writeq arch/x86/include/asm/io.h:98 [inline] RIP: 0010:bitfill_aligned+0x1d2/0x270 drivers/video/fbdev/core/cfbfillrect.c:75 Code: 39 1b fd eb 09 e8 3e 39 1b fd 48 83 c3 40 31 ff 89 ee e8 41 3d 1b fd 85 ed 74 2c 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 ff cd <4c> 89 33 85 ed 74 0b 48 83 c3 08 e8 0e 39 1b fd eb ec e8 07 39 1b RSP: 0018:ffffc90002b4ee38 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff888001000030 RCX: ffff888020209d00 RDX: ffff888020209d00 RSI: 0000000000000002 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffffff84695e4f R09: 0000000000000040 R10: 0000000000000002 R11: ffff888020209d00 R12: ffffffffffffffff R13: 0000000000000080 R14: 0000000000000000 R15: 0000000000000000 FS: 0000555555c14300(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff888001000030 CR3: 00000000708fb000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> cfb_fillrect+0x5d8/0x800 drivers/video/fbdev/core/cfbfillrect.c:327 bit_clear_margins+0x2d7/0x6e0 drivers/video/fbdev/core/bitblit.c:209 fbcon_clear_margins drivers/video/fbdev/core/fbcon.c:1296 [inline] fbcon_switch+0x1569/0x21f0 drivers/video/fbdev/core/fbcon.c:1677 redraw_screen+0x53d/0x1280 drivers/tty/vt/vt.c:1021 vc_do_resize+0x1361/0x1930 drivers/tty/vt/vt.c:1342 fbcon_do_set_font+0x9ef/0x10d0 drivers/video/fbdev/core/fbcon.c:1928 fbcon_set_font+0x9f9/0xc80 drivers/video/fbdev/core/fbcon.c:2014 con_font_set drivers/tty/vt/vt.c:4666 [inline] con_font_op+0xbcd/0x1080 drivers/tty/vt/vt.c:4710 vt_k_ioctl drivers/tty/vt/vt_ioctl.c:474 [inline] vt_ioctl+0x1838/0x3860 drivers/tty/vt/vt_ioctl.c:752 tty_ioctl+0xfb2/0x17d0 drivers/tty/tty_io.c:2805 vfs_ioctl fs/ioctl.c:51 [inline] __do_sys_ioctl fs/ioctl.c:874 [inline] __se_sys_ioctl+0xfb/0x170 fs/ioctl.c:860 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f44f1232229 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 b1 14 00 00 90 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:00007fffb8c823a8 EFLAGS: 00000246 ORIG_RAX: 0000000000000010 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f44f1232229 RDX: 0000000020000400 RSI: 0000000000004b72 RDI: 0000000000000004 RBP: 0000000000000000 R08: 000000000000000d R09: 00007fffb8c82548 R10: 0000000000000000 R11: 0000000000000246 R12: 00007f44f11f5820 R13: 431bde82d7b634db R14: 0000000000000000 R15: 0000000000000000 </TASK> Modules linked in: CR2: ffff888001000030 ---[ end trace 3cf2fa8eab0f5f7d ]--- RIP: 0010:__writeq arch/x86/include/asm/io.h:98 [inline] RIP: 0010:bitfill_aligned+0x1d2/0x270 drivers/video/fbdev/core/cfbfillrect.c:75 Code: 39 1b fd eb 09 e8 3e 39 1b fd 48 83 c3 40 31 ff 89 ee e8 41 3d 1b fd 85 ed 74 2c 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 ff cd <4c> 89 33 85 ed 74 0b 48 83 c3 08 e8 0e 39 1b fd eb ec e8 07 39 1b RSP: 0018:ffffc90002b4ee38 EFLAGS: 00010202 RAX: 0000000000000000 RBX: ffff888001000030 RCX: ffff888020209d00 RDX: ffff888020209d00 RSI: 0000000000000002 RDI: 0000000000000000 RBP: 0000000000000001 R08: ffffffff84695e4f R09: 0000000000000040 R10: 0000000000000002 R11: ffff888020209d00 R12: ffffffffffffffff R13: 0000000000000080 R14: 0000000000000000 R15: 0000000000000000 FS: 0000555555c14300(0000) GS:ffff8880b9a00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffff888001000030 CR3: 00000000708fb000 CR4: 00000000003506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 39 1b cmp %ebx,(%rbx) 2: fd std 3: eb 09 jmp 0xe 5: e8 3e 39 1b fd callq 0xfd1b3948 a: 48 83 c3 40 add $0x40,%rbx e: 31 ff xor %edi,%edi 10: 89 ee mov %ebp,%esi 12: e8 41 3d 1b fd callq 0xfd1b3d58 17: 85 ed test %ebp,%ebp 19: 74 2c je 0x47 1b: 66 2e 0f 1f 84 00 00 nopw %cs:0x0(%rax,%rax,1) 22: 00 00 00 25: 0f 1f 00 nopl (%rax) 28: ff cd dec %ebp * 2a: 4c 89 33 mov %r14,(%rbx) <-- trapping instruction 2d: 85 ed test %ebp,%ebp 2f: 74 0b je 0x3c 31: 48 83 c3 08 add $0x8,%rbx 35: e8 0e 39 1b fd callq 0xfd1b3948 3a: eb ec jmp 0x28 3c: e8 .byte 0xe8 3d: 07 (bad) 3e: 39 1b cmp %ebx,(%rbx)