[PATCH 6.6.y] usb: gadget: uvc: Fix ERR_PTR dereference in uvc_v4l2.c - Linux-stable-mirror

3 Apr 2025

From: Abhishek Tamboli abhishektamboli9@gmail.com
[ Upstream commit a7bb96b18864225a694e3887ac2733159489e4b0 ]
Fix potential dereferencing of ERR_PTR() in find_format_by_pix()
and uvc_v4l2_enum_format().
Fix the following smatch errors:
drivers/usb/gadget/function/uvc_v4l2.c:124 find_format_by_pix()
error: 'fmtdesc' dereferencing possible ERR_PTR()
drivers/usb/gadget/function/uvc_v4l2.c:392 uvc_v4l2_enum_format()
error: 'fmtdesc' dereferencing possible ERR_PTR()
Also, fix similar issue in uvc_v4l2_try_format() for potential
dereferencing of ERR_PTR().
Signed-off-by: Abhishek Tamboli abhishektamboli9@gmail.com
Link: https://lore.kernel.org/r/20240815102202.594812-1-abhishektamboli9@gmail.com
Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
Signed-off-by: Jianqi Ren jianqi.ren.cn@windriver.com
Signed-off-by: He Zhe zhe.he@windriver.com
---
Verified the build test
---
 drivers/usb/gadget/function/uvc_v4l2.c | 12 +++++++++++-
 1 file changed, 11 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/gadget/function/uvc_v4l2.c b/drivers/usb/gadget/function/uvc_v4l2.c
index 3f0a9795c0d4..0195625bef53 100644
--- a/drivers/usb/gadget/function/uvc_v4l2.c
+++ b/drivers/usb/gadget/function/uvc_v4l2.c
@@ -121,6 +121,9 @@ static struct uvcg_format *find_format_by_pix(struct uvc_device *uvc,
    list_for_each_entry(format, &uvc->header->formats, entry) {
    	const struct uvc_format_desc *fmtdesc = to_uvc_format(format->fmt);
+		if (IS_ERR(fmtdesc))
+			continue;
+
    	if (fmtdesc->fcc == pixelformat) {
    		uformat = format->fmt;
    		break;
@@ -240,6 +243,7 @@ uvc_v4l2_try_format(struct file *file, void *fh, struct v4l2_format *fmt)
    struct uvc_video *video = &uvc->video;
    struct uvcg_format *uformat;
    struct uvcg_frame *uframe;
+	const struct uvc_format_desc *fmtdesc;
    u8 *fcc;
if (fmt->type != video->queue.queue.type)
@@ -265,7 +269,10 @@ uvc_v4l2_try_format(struct file *file, void *fh, struct v4l2_format *fmt)
    fmt->fmt.pix.field = V4L2_FIELD_NONE;
    fmt->fmt.pix.bytesperline = uvc_v4l2_get_bytesperline(uformat, uframe);
    fmt->fmt.pix.sizeimage = uvc_get_frame_size(uformat, uframe);
-	fmt->fmt.pix.pixelformat = to_uvc_format(uformat)->fcc;
+	fmtdesc = to_uvc_format(uformat);
+	if (IS_ERR(fmtdesc))
+		return PTR_ERR(fmtdesc);
+	fmt->fmt.pix.pixelformat = fmtdesc->fcc;
    fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
    fmt->fmt.pix.priv = 0;
@@ -375,6 +382,9 @@ uvc_v4l2_enum_format(struct file *file, void *fh, struct v4l2_fmtdesc *f)
    	return -EINVAL;
fmtdesc = to_uvc_format(uformat);
+	if (IS_ERR(fmtdesc))
+		return PTR_ERR(fmtdesc);
+
    f->pixelformat = fmtdesc->fcc;
return 0;
-- 
2.34.1



    