From: Seung-Woo Kim sw0312.kim@samsung.com
[ Upstream commit 4d741cbd58bf889c8a68cf6e592a7892b5c2802e ]
When driver is built as module and probe during insmod is deferred because of sensor subdevs, there is NULL pointer deference because mdev is cleaned up and then access it from v4l2_device_unregister(). Fix the wrong mdev and v4l2 dev order in error path of probe.
This fixes below null pointer deference: Unable to handle kernel NULL pointer dereference at virtual address 00000000 pgd = ca026f68 [00000000] *pgd=00000000 Internal error: Oops: 5 [#1] PREEMPT SMP ARM [...] Hardware name: SAMSUNG EXYNOS (Flattened Device Tree) PC is at ida_free+0x7c/0x160 LR is at xas_start+0x44/0x204 [...] [<c0dafd60>] (ida_free) from [<c083c20c>] (__media_device_unregister_entity+0x18/0xc0) [<c083c20c>] (__media_device_unregister_entity) from [<c083c2e0>] (media_device_unregister_entity+0x2c/0x38) [<c083c2e0>] (media_device_unregister_entity) from [<c0843404>] (v4l2_device_release+0xd0/0x104) [<c0843404>] (v4l2_device_release) from [<c0632558>] (device_release+0x28/0x98) [<c0632558>] (device_release) from [<c0db1204>] (kobject_put+0xa4/0x208) [<c0db1204>] (kct_put) from [<bf00bac4>] (fimc_capture_subdev_unregistered+0x58/0x6c [s5p_fimc]) [<bf00bac4>] (fimc_capture_subdev_unregistered [s5p_fimc]) from [<c084a1cc>] (v4l2_device_unregister_subdev+0x6c/0xa8) [<c084a1cc>] (v4l2_device_unregister_subdev) from [<c084a350>] (v4l2_device_unregister+0x64/0x94) [<c084a350>] (v4l2_device_unregister) from [<bf0101ac>] (fimc_md_probe+0x4ec/0xaf8 [s5p_fimc]) [...]
Signed-off-by: Seung-Woo Kim sw0312.kim@samsung.com Reviewed-by: Sylwester Nawrocki s.nawrocki@samsung.com Fixes: 9832e155f1ed ("[media] media-device: split media initialization and registration") Signed-off-by: Hans Verkuil hverkuil-cisco@xs4all.nl Signed-off-by: Mauro Carvalho Chehab mchehab@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/media/platform/exynos4-is/media-dev.c | 7 ++++--- 1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/drivers/media/platform/exynos4-is/media-dev.c b/drivers/media/platform/exynos4-is/media-dev.c index a838189d4490..9aaf3b8060d5 100644 --- a/drivers/media/platform/exynos4-is/media-dev.c +++ b/drivers/media/platform/exynos4-is/media-dev.c @@ -1457,12 +1457,12 @@ static int fimc_md_probe(struct platform_device *pdev) ret = v4l2_device_register(dev, &fmd->v4l2_dev); if (ret < 0) { v4l2_err(v4l2_dev, "Failed to register v4l2_device: %d\n", ret); - return ret; + goto err_md; }
ret = fimc_md_get_clocks(fmd); if (ret) - goto err_md; + goto err_v4l2dev;
ret = fimc_md_get_pinctrl(fmd); if (ret < 0) { @@ -1519,9 +1519,10 @@ err_m_ent: fimc_md_unregister_entities(fmd); err_clk: fimc_md_put_clocks(fmd); +err_v4l2dev: + v4l2_device_unregister(&fmd->v4l2_dev); err_md: media_device_cleanup(&fmd->media_dev); - v4l2_device_unregister(&fmd->v4l2_dev); return ret; }