2021-03-10 00:18:43

by Ricardo Ribalda

[permalink] [raw]
Subject: [PATCH] media: staging/intel-ipu3: Fix set_fmt error handling

If there in an error during a set_fmt, do not overwrite the previous
sizes with the invalid config.

Without this patch, v4l2-compliance ends up allocating 4GiB of RAM and
causing the following OOPs

[ 38.662975] ipu3-imgu 0000:00:05.0: swiotlb buffer is full (sz: 4096 bytes)
[ 38.662980] DMA: Out of SW-IOMMU space for 4096 bytes at device 0000:00:05.0
[ 38.663010] general protection fault: 0000 [#1] PREEMPT SMP

Cc: [email protected]
Fixes: 6d5f26f2e045 ("media: staging/intel-ipu3-v4l: reduce kernel stack usage")
Signed-off-by: Ricardo Ribalda <[email protected]>
---
drivers/staging/media/ipu3/ipu3-v4l2.c | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/drivers/staging/media/ipu3/ipu3-v4l2.c b/drivers/staging/media/ipu3/ipu3-v4l2.c
index 60aa02eb7d2a..e8944e489c56 100644
--- a/drivers/staging/media/ipu3/ipu3-v4l2.c
+++ b/drivers/staging/media/ipu3/ipu3-v4l2.c
@@ -669,6 +669,7 @@ static int imgu_fmt(struct imgu_device *imgu, unsigned int pipe, int node,
struct imgu_css_pipe *css_pipe = &imgu->css.pipes[pipe];
struct imgu_media_pipe *imgu_pipe = &imgu->imgu_pipe[pipe];
struct imgu_v4l2_subdev *imgu_sd = &imgu_pipe->imgu_sd;
+ struct v4l2_pix_format_mplane fmt_backup;

dev_dbg(dev, "set fmt node [%u][%u](try = %u)", pipe, node, try);

@@ -734,6 +735,7 @@ static int imgu_fmt(struct imgu_device *imgu, unsigned int pipe, int node,
ret = -EINVAL;
goto out;
}
+ fmt_backup = *fmts[css_q];
*fmts[css_q] = f->fmt.pix_mp;

if (try)
@@ -741,6 +743,9 @@ static int imgu_fmt(struct imgu_device *imgu, unsigned int pipe, int node,
else
ret = imgu_css_fmt_set(&imgu->css, fmts, rects, pipe);

+ if (try || ret < 0)
+ *fmts[css_q] = fmt_backup;
+
/* ret is the binary number in the firmware blob */
if (ret < 0)
goto out;
--
2.30.1.766.gb4fecdf3b7-goog