]> git.ipfire.org Git - thirdparty/kernel/stable.git/commit
media: sti: bdisp: fix a possible sleep-in-atomic-context bug in bdisp_device_run()
authorJia-Ju Bai <baijiaju1990@gmail.com>
Thu, 19 Dec 2019 10:34:01 +0000 (11:34 +0100)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Fri, 28 Feb 2020 14:42:18 +0000 (15:42 +0100)
commit4986129b7013bcec51579163e6cea01a9d57d6c2
tree9b03f5c0a1fdbb3ba435c39406db2bfe5c26ef05
parentfd0faee0f5bc19ac5226f1c3465dd4200311afc2
media: sti: bdisp: fix a possible sleep-in-atomic-context bug in bdisp_device_run()

[ Upstream commit bb6d42061a05d71dd73f620582d9e09c8fbf7f5b ]

The driver may sleep while holding a spinlock.
The function call path (from bottom to top) in Linux 4.19 is:

drivers/media/platform/sti/bdisp/bdisp-hw.c, 385:
    msleep in bdisp_hw_reset
drivers/media/platform/sti/bdisp/bdisp-v4l2.c, 341:
    bdisp_hw_reset in bdisp_device_run
drivers/media/platform/sti/bdisp/bdisp-v4l2.c, 317:
    _raw_spin_lock_irqsave in bdisp_device_run

To fix this bug, msleep() is replaced with udelay().

This bug is found by a static analysis tool STCheck written by myself.

Signed-off-by: Jia-Ju Bai <baijiaju1990@gmail.com>
Reviewed-by: Fabien Dessenne <fabien.dessenne@st.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
drivers/media/platform/sti/bdisp/bdisp-hw.c