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INFO: task hung in do_fb_ioctl

Status: closed as dup on 2020/07/27 22:56
Subsystems: fbdev
[Documentation on labels]
Reported-by: syzbot+3f3e624036e240d8aa36@syzkaller.appspotmail.com
First crash: 1559d, last: 1350d
▶ ▼ Duplicate of
Title Repro Cause bisect Fix bisect Count Last Reported
KASAN: vmalloc-out-of-bounds Write in bitfill_aligned fbdev C 475 1362d 1596d
▶ ▼ Discussions (1)
Title Replies (including bot) Last reply
INFO: task hung in do_fb_ioctl 0 (1) 2020/01/12 07:15
▶ ▼ Similar bugs (6)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream INFO: task hung in do_fb_ioctl (4) fbdev 1 340d 340d 0/26 auto-obsoleted due to no activity on 2023/07/13 16:33
upstream INFO: task hung in do_fb_ioctl (3) fbdev 2 566d 591d 0/26 auto-obsoleted due to no activity on 2023/01/02 23:29
upstream INFO: task hung in do_fb_ioctl (2) fbdev 1 786d 786d 0/26 auto-closed as invalid on 2022/05/22 20:52
linux-4.19 INFO: task hung in do_fb_ioctl 1 1560d 1560d 0/1 auto-closed as invalid on 2020/05/08 18:42
linux-4.14 INFO: task hung in do_fb_ioctl C error 24 1239d 1598d 0/1 upstream: reported C repro on 2019/12/03 05:09
linux-4.19 INFO: task hung in do_fb_ioctl (2) C done 7 970d 1385d 1/1 fixed on 2021/09/21 12:35

Sample crash report:
INFO: task syz-executor.2:28148 blocked for more than 143 seconds.
      Not tainted 5.8.0-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
syz-executor.2  D28560 28148   7039 0x00000004
Call Trace:
 context_switch kernel/sched/core.c:3778 [inline]
 __schedule+0x8e5/0x21e0 kernel/sched/core.c:4527
 schedule+0xd0/0x2a0 kernel/sched/core.c:4602
 schedule_timeout+0x1d8/0x250 kernel/time/timer.c:1855
 __down_common kernel/locking/semaphore.c:220 [inline]
 __down+0x183/0x2a0 kernel/locking/semaphore.c:237
 down+0x57/0x80 kernel/locking/semaphore.c:61
 console_lock+0x25/0x80 kernel/printk/printk.c:2317
 do_fb_ioctl+0x2df/0x6c0 drivers/video/fbdev/core/fbmem.c:1106
 fb_ioctl+0xdd/0x130 drivers/video/fbdev/core/fbmem.c:1185
 vfs_ioctl fs/ioctl.c:48 [inline]
 ksys_ioctl+0x11a/0x180 fs/ioctl.c:753
 __do_sys_ioctl fs/ioctl.c:762 [inline]
 __se_sys_ioctl fs/ioctl.c:760 [inline]
 __x64_sys_ioctl+0x6f/0xb0 fs/ioctl.c:760
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45ccd9
Code: Bad RIP value.
RSP: 002b:00007f07f57dfc78 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 000000000000d540 RCX: 000000000045ccd9
RDX: 0000000020000000 RSI: 0000000000004601 RDI: 0000000000000003
RBP: 000000000078bf40 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 000000000078bf0c
R13: 00007ffe88aadb6f R14: 00007f07f57e09c0 R15: 000000000078bf0c

Showing all locks held in the system:
1 lock held by khungtaskd/1151:
 #0: ffffffff89bd6980 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x53/0x260 kernel/locking/lockdep.c:5825
1 lock held by in:imklog/6528:
 #0: ffff8880a2bb7e30 (&f->f_pos_lock){+.+.}-{3:3}, at: __fdget_pos+0xe9/0x100 fs/file.c:930
2 locks held by agetty/6770:
 #0: ffff8880a5c43098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x22/0x80 drivers/tty/tty_ldisc.c:267
 #1: ffffc90000fd42e8 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x223/0x1a30 drivers/tty/n_tty.c:2156
5 locks held by syz-executor.4/28145:

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 1151 Comm: khungtaskd Not tainted 5.8.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 __dump_stack lib/dump_stack.c:77 [inline]
 dump_stack+0x18f/0x20d lib/dump_stack.c:118
 nmi_cpu_backtrace.cold+0x70/0xb1 lib/nmi_backtrace.c:101
 nmi_trigger_cpumask_backtrace+0x1b3/0x223 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:146 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:209 [inline]
 watchdog+0xd7d/0x1000 kernel/hung_task.c:295
 kthread+0x3b5/0x4a0 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:294
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 28145 Comm: syz-executor.4 Not tainted 5.8.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__sanitizer_cov_trace_pc+0x45/0x60 kernel/kcov.c:202
Code: f6 c4 01 74 35 8b 82 04 14 00 00 85 c0 74 2b 8b 82 e0 13 00 00 83 f8 02 75 20 48 8b 8a e8 13 00 00 8b 92 e4 13 00 00 48 8b 01 <48> 83 c0 01 48 39 c2 76 07 48 89 34 c1 48 89 01 c3 66 2e 0f 1f 84
RSP: 0018:ffffc900089471a0 EFLAGS: 00000246
RAX: 000000000003ffff RBX: 0000000000000012 RCX: ffffc90011f45000
RDX: 0000000000040000 RSI: ffffffff83c80190 RDI: 0000000000000004
RBP: 000000000000000c R08: 0000000000000010 R09: 0000000000000090
R10: 0000000000000012 R11: 0000000000000001 R12: ffff8880000a000c
R13: ffff8880000a0000 R14: 0000000000000000 R15: 00000000032c8fe9
FS:  00007f655f76a700(0000) GS:ffff8880ae700000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f88b69da740 CR3: 000000004a0b3000 CR4: 00000000001526e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 writeb arch/x86/include/asm/io.h:65 [inline]
 vga16fb_fillrect+0x9c0/0x193b drivers/video/fbdev/vga16fb.c:923
 bit_clear+0x386/0x4d0 drivers/video/fbdev/core/bitblit.c:74
 fbcon_clear+0x519/0x5a0 drivers/video/fbdev/core/fbcon.c:1351
 fbcon_scroll+0x1e20/0x3600 drivers/video/fbdev/core/fbcon.c:1980
 con_scroll+0x5b9/0x6d0 drivers/tty/vt/vt.c:637
 lf+0x262/0x2b0 drivers/tty/vt/vt.c:1489
 do_con_write+0x208c/0x7400 drivers/tty/vt/vt.c:2787
 con_write+0x22/0xb0 drivers/tty/vt/vt.c:3165
 process_output_block drivers/tty/n_tty.c:595 [inline]
 n_tty_write+0x3ce/0xf80 drivers/tty/n_tty.c:2333
 do_tty_write drivers/tty/tty_io.c:962 [inline]
 tty_write+0x4d9/0x870 drivers/tty/tty_io.c:1046
 __kernel_write+0x199/0x500 fs/read_write.c:528
 write_pipe_buf+0x153/0x1f0 fs/splice.c:799
 splice_from_pipe_feed fs/splice.c:502 [inline]
 __splice_from_pipe+0x3dc/0x830 fs/splice.c:626
 splice_from_pipe fs/splice.c:661 [inline]
 default_file_splice_write fs/splice.c:811 [inline]
 do_splice_from fs/splice.c:847 [inline]
 direct_splice_actor+0x228/0x2f0 fs/splice.c:1016
 splice_direct_to_actor+0x38c/0x980 fs/splice.c:971
 do_splice_direct+0x1b3/0x280 fs/splice.c:1059
 do_sendfile+0x559/0xc30 fs/read_write.c:1540
 __do_sys_sendfile64 fs/read_write.c:1595 [inline]
 __se_sys_sendfile64 fs/read_write.c:1587 [inline]
 __x64_sys_sendfile64+0x149/0x210 fs/read_write.c:1587
 do_syscall_64+0x2d/0x70 arch/x86/entry/common.c:46
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x45ccd9
Code: 2d b6 fb ff c3 66 2e 0f 1f 84 00 00 00 00 00 66 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 0f 83 fb b5 fb ff c3 66 2e 0f 1f 84 00 00 00 00
RSP: 002b:00007f655f769c78 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 0000000000026b80 RCX: 000000000045ccd9
RDX: 0000000020000040 RSI: 0000000000000004 RDI: 0000000000000006
RBP: 000000000078bf48 R08: 0000000000000000 R09: 0000000000000000
R10: 000000000000a808 R11: 0000000000000246 R12: 000000000078bf0c
R13: 00007ffd9cf1ce1f R14: 00007f655f76a9c0 R15: 000000000078bf0c

Crashes (47):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/08/07 04:26 upstream 47ec5303d73e 1f122f88 .config console log report ci-upstream-kasan-gce-selinux-root
2020/07/26 13:20 upstream 04300d66f0a0 51265195 .config console log report ci-upstream-kasan-gce
2020/07/25 19:22 upstream 68845a55c31b 1f7cc1ca .config console log report ci-upstream-kasan-gce
2020/07/24 14:00 upstream f37e99aca03f 554af388 .config console log report ci-upstream-kasan-gce
2020/07/24 02:48 upstream d15be546031c 70c104a1 .config console log report ci-upstream-kasan-gce
2020/07/21 22:23 upstream 4fa640dc5230 21f1765e .config console log report ci-upstream-kasan-gce
2020/07/20 18:54 upstream 5714ee50bb43 4285ffa3 .config console log report ci-upstream-kasan-gce
2020/07/19 19:34 upstream f932d58abc38 9c812472 .config console log report ci-upstream-kasan-gce-selinux-root
2020/07/17 23:55 upstream 8882572675c1 9c812472 .config console log report ci-upstream-kasan-gce
2020/07/16 17:53 upstream 994e99a96c9b f3bec699 .config console log report ci-upstream-kasan-gce
2020/07/11 20:09 upstream a581387e415b 18d18b59 .config console log report ci-upstream-kasan-gce-selinux-root
2020/07/11 19:09 upstream a581387e415b 18d18b59 .config console log report ci-upstream-kasan-gce
2020/07/07 11:44 upstream 7cc2a8ea1048 51095195 .config console log report ci-upstream-kasan-gce-root
2020/07/06 06:53 upstream 7cc2a8ea1048 51095195 .config console log report ci-upstream-kasan-gce-root
2020/07/05 14:18 upstream 7cc2a8ea1048 51095195 .config console log report ci-upstream-kasan-gce
2020/07/01 18:32 upstream 7c30b859a947 39acb39d .config console log report ci-upstream-kasan-gce-selinux-root
2020/07/01 07:51 upstream 9ebcfadb0610 917afeaa .config console log report ci-upstream-kasan-gce-selinux-root
2020/06/29 13:30 upstream 4e99b32169e8 a2cdad9d .config console log report ci-upstream-kasan-gce
2020/06/28 02:59 upstream 1590a2e1c681 ffec44b5 .config console log report ci-upstream-kasan-gce-root
2020/06/25 14:14 upstream 7ae77150d94d 54566aff .config console log report ci-upstream-kasan-gce
2020/06/24 19:01 upstream 7ae77150d94d 54566aff .config console log report ci-upstream-kasan-gce
2020/06/21 18:28 upstream 7ae77150d94d 4f2acff9 .config console log report ci-upstream-kasan-gce
2020/06/08 17:40 upstream 7ae77150d94d 7604bb03 .config console log report ci-upstream-kasan-gce
2020/06/06 22:36 upstream 7ae77150d94d e6b89e4e .config console log report ci-upstream-kasan-gce
2020/06/04 13:54 upstream cb8e59cc8720 b0d1c0d5 .config console log report ci-upstream-kasan-gce
2020/05/12 02:43 upstream 152036d1379f 9eb09c40 .config console log report ci-upstream-kasan-gce
2020/04/28 06:35 upstream 51184ae37e05 0ce7569e .config console log report ci-upstream-kasan-gce-selinux-root
2020/04/23 09:29 upstream c578ddb39e56 2e44d63e .config console log report ci-upstream-kasan-gce
2020/04/20 22:02 upstream ae83d0b416db 347a5dc3 .config console log report ci-upstream-kasan-gce-selinux-root
2020/04/16 15:59 upstream 00086336a8d9 c743fcb3 .config console log report ci-upstream-kasan-gce-smack-root
2020/04/15 18:34 upstream 8632e9b5645b 3f3c5574 .config console log report ci-upstream-kasan-gce
2020/04/14 06:27 upstream 8f3d9f354286 7c54686a .config console log report ci-upstream-kasan-gce-root
2020/04/14 06:15 upstream 8f3d9f354286 7c54686a .config console log report ci-upstream-kasan-gce-smack-root
2020/04/10 02:55 upstream 5d30bcacd91a a8c6a3f8 .config console log report ci-upstream-kasan-gce
2020/03/26 19:32 upstream 1b649e0bcae7 6d25c5a0 .config console log report ci-upstream-kasan-gce-root
2020/03/22 16:04 upstream b74b991fb8b9 78267cec .config console log report ci-upstream-kasan-gce-selinux-root
2020/02/02 01:54 upstream 94f2630b1897 2274ad39 .config console log report ci-upstream-kasan-gce-selinux-root
2020/01/30 16:22 upstream 39bed42de2e7 5ed23f9a .config console log report ci-upstream-kasan-gce-root
2020/01/24 19:26 upstream 4703d9119972 2e95ab33 .config console log report ci-upstream-kasan-gce-smack-root
2020/01/20 07:53 upstream def9d2780727 0342f8c7 .config console log report ci-upstream-kasan-gce
2020/01/11 06:57 upstream e69ec487b2c7 4de4e9f0 .config console log report ci-upstream-kasan-gce
2020/07/24 06:08 upstream d15be546031c 70c104a1 .config console log report ci-upstream-kasan-gce-386
2020/07/18 08:02 upstream 8882572675c1 9c812472 .config console log report ci-upstream-kasan-gce-386
2020/06/17 19:00 upstream 7ae77150d94d b9f3810b .config console log report ci-upstream-kasan-gce-386
2020/01/30 21:41 upstream 39bed42de2e7 5ed23f9a .config console log report ci-upstream-kasan-gce-386
2020/07/19 00:56 linux-next 4c43049f19a2 9c812472 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/05/10 09:11 linux-next ac935d227366 8742a2b9 .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.