general protection fault, probably for non-canonical address 0xdffffc000000007e: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x00000000000003f0-0x00000000000003f7] CPU: 1 PID: 15999 Comm: syz-executor.5 Not tainted 6.6.0-rc2-syzkaller-00018-g2cf0f7156238 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023 RIP: 0010:__fb_pad_aligned_buffer include/linux/fb.h:629 [inline] RIP: 0010:bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] RIP: 0010:bit_putcs+0x62b/0xde0 drivers/video/fbdev/core/bitblit.c:185 Code: 64 24 5c 4c 8b 7c 24 28 49 83 c4 01 eb 03 44 89 ed e8 79 9f 1d fd 48 89 df 48 83 c3 01 48 89 f8 48 89 fa 48 c1 e8 03 83 e2 07 <42> 0f b6 04 30 38 d0 7f 08 84 c0 0f 85 19 04 00 00 4c 89 f8 4c 89 RSP: 0018:ffffc90014edf408 EFLAGS: 00010246 RAX: 000000000000007e RBX: 00000000000003f1 RCX: ffffc90004a29000 RDX: 0000000000000000 RSI: ffffffff846a26b7 RDI: 00000000000003f0 RBP: 000000000000000f R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000010 R11: 0000000000000000 R12: 0000000000000001 R13: ffff8881452c5020 R14: dffffc0000000000 R15: ffff8881452c5020 FS: 00007f55520676c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000001b2f823000 CR3: 0000000020a72000 CR4: 0000000000350ee0 Call Trace: fbcon_putcs+0x314/0x3d0 drivers/video/fbdev/core/fbcon.c:1282 con_flush drivers/tty/vt/vt.c:2571 [inline] vc_con_write_normal drivers/tty/vt/vt.c:2842 [inline] do_con_write+0x11eb/0x7f40 drivers/tty/vt/vt.c:2909 con_put_char+0x74/0xa0 drivers/tty/vt/vt.c:3253 tty_put_char+0xbc/0x150 drivers/tty/tty_io.c:3140 do_output_char+0x151/0x830 drivers/tty/n_tty.c:474 process_output drivers/tty/n_tty.c:499 [inline] n_tty_write+0x4c9/0x1130 drivers/tty/n_tty.c:2395 iterate_tty_write drivers/tty/tty_io.c:1017 [inline] file_tty_write.constprop.0+0x519/0x9b0 drivers/tty/tty_io.c:1088 call_write_iter include/linux/fs.h:1985 [inline] do_iter_readv_writev+0x21e/0x3c0 fs/read_write.c:735 do_iter_write+0x17f/0x830 fs/read_write.c:860 vfs_writev+0x221/0x700 fs/read_write.c:933 do_writev+0x137/0x370 fs/read_write.c:976 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x38/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7f555127cae9 Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 e1 20 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 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f55520670c8 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007f555139bf80 RCX: 00007f555127cae9 RDX: 0000000000000003 RSI: 00000000200002c0 RDI: 0000000000000003 RBP: 00007f55512c847a R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007f555139bf80 R15: 00007ffc3ab7c088 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__fb_pad_aligned_buffer include/linux/fb.h:629 [inline] RIP: 0010:bit_putcs_aligned drivers/video/fbdev/core/bitblit.c:96 [inline] RIP: 0010:bit_putcs+0x62b/0xde0 drivers/video/fbdev/core/bitblit.c:185 Code: 64 24 5c 4c 8b 7c 24 28 49 83 c4 01 eb 03 44 89 ed e8 79 9f 1d fd 48 89 df 48 83 c3 01 48 89 f8 48 89 fa 48 c1 e8 03 83 e2 07 <42> 0f b6 04 30 38 d0 7f 08 84 c0 0f 85 19 04 00 00 4c 89 f8 4c 89 RSP: 0018:ffffc90014edf408 EFLAGS: 00010246 RAX: 000000000000007e RBX: 00000000000003f1 RCX: ffffc90004a29000 RDX: 0000000000000000 RSI: ffffffff846a26b7 RDI: 00000000000003f0 RBP: 000000000000000f R08: 0000000000000005 R09: 0000000000000000 R10: 0000000000000010 R11: 0000000000000000 R12: 0000000000000001 R13: ffff8881452c5020 R14: dffffc0000000000 R15: ffff8881452c5020 FS: 00007f55520676c0(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f5f2036ff00 CR3: 0000000020a72000 CR4: 0000000000350ee0 ---------------- Code disassembly (best guess): 0: 64 24 5c fs and $0x5c,%al 3: 4c 8b 7c 24 28 mov 0x28(%rsp),%r15 8: 49 83 c4 01 add $0x1,%r12 c: eb 03 jmp 0x11 e: 44 89 ed mov %r13d,%ebp 11: e8 79 9f 1d fd call 0xfd1d9f8f 16: 48 89 df mov %rbx,%rdi 19: 48 83 c3 01 add $0x1,%rbx 1d: 48 89 f8 mov %rdi,%rax 20: 48 89 fa mov %rdi,%rdx 23: 48 c1 e8 03 shr $0x3,%rax 27: 83 e2 07 and $0x7,%edx * 2a: 42 0f b6 04 30 movzbl (%rax,%r14,1),%eax <-- trapping instruction 2f: 38 d0 cmp %dl,%al 31: 7f 08 jg 0x3b 33: 84 c0 test %al,%al 35: 0f 85 19 04 00 00 jne 0x454 3b: 4c 89 f8 mov %r15,%rax 3e: 4c rex.WR 3f: 89 .byte 0x89