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From: Jia-Ju Bai <baijiaju1990@gmail.com>
To: akpm@linux-foundation.org, dvyukov@google.com,
	Greg KH <gregkh@linuxfoundation.org>,
	tchibo@google.com, aryabinin@virtuozzo.com
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: [BUG] kernel: kcov: a possible sleep-in-atomic-context bug in kcov_ioctl()
Date: Thu, 21 Jun 2018 11:20:59 +0800	[thread overview]
Message-ID: <ca2e4f0b-dd08-8d66-51e3-05cc69e15d65@gmail.com> (raw)

The kernel may sleep with holding a spinlock.
The function call path (from bottom to top) in Linux-4.16.7 is:

[FUNC] vfree --> can sleep
kernel/kcov.c, 237: vfree in kcov_put
kernel/kcov.c, 396: kcov_put in kcov_ioctl_locked
kernel/kcov.c, 410: kcov_ioctl_locked in kcov_ioctl
kernel/kcov.c, 409: spin_lock in kcov_ioctl

This bug is found by my static analysis tool (DSAC-2) and checked by my
code review.

I do not know how to correctly fix this bug, so I just report them.


Best wishes,
Jia-Ju Bai

             reply	other threads:[~2018-06-21  3:21 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-06-21  3:20 Jia-Ju Bai [this message]
2018-06-21  3:43 ` Al Viro
2018-06-21  3:50   ` Jia-Ju Bai
2019-12-17 12:56 Jia-Ju Bai
2019-12-17 13:02 ` Dmitry Vyukov
2019-12-17 13:11   ` Jia-Ju Bai
2019-12-17 13:13     ` Dmitry Vyukov
2019-12-17 13:17       ` Jia-Ju Bai

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