syzbot


WARNING: lock held when returning to user space in tun_get_user (2)

Status: fixed on 2020/02/18 14:31
Subsystems: net
[Documentation on labels]
Fix commit: 1efba987c486 net-backports: tun: add mutex_unlock() call and napi.skb clearing in tun_get_user()
First crash: 1543d, last: 1532d
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING: lock held when returning to user space in tun_get_user net C done 55 1854d 1855d 12/26 fixed on 2019/04/10 16:37

Sample crash report:
================================================
WARNING: lock held when returning to user space!
5.5.0-rc6-syzkaller #0 Not tainted
------------------------------------------------
syz-executor.4/27416 is leaving the kernel with locks still held!
1 lock held by syz-executor.4/27416:
 #0: ffff888061b44748 (&tfile->napi_mutex){+.+.}, at: tun_get_user+0x1604/0x3fc0 drivers/net/tun.c:1835

Crashes (7):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/01/26 03:35 net-next-old 3333e50b64fe f4e7270e .config console log report ci-upstream-net-kasan-gce
2020/01/25 05:14 net-next-old 23f4eacdd24a 2e95ab33 .config console log report ci-upstream-net-kasan-gce
2020/01/22 20:29 net-next-old 4f2c17e0f332 8eda0b95 .config console log report ci-upstream-net-kasan-gce
2020/01/22 18:59 net-next-old 4f2c17e0f332 8eda0b95 .config console log report ci-upstream-net-kasan-gce
2020/01/22 10:54 net-next-old 4f2c17e0f332 8eda0b95 .config console log report ci-upstream-net-kasan-gce
2020/02/02 10:13 linux-next 2747d5fdab78 2274ad39 .config console log report ci-upstream-linux-next-kasan-gce-root
2020/01/31 01:57 linux-next 2747d5fdab78 5ed23f9a .config console log report ci-upstream-linux-next-kasan-gce-root
* Struck through repros no longer work on HEAD.