[PATCH AUTOSEL 6.10 58/70] usb: gadget: uvc: Fix ERR_PTR dereference in uvc_v4l2.c

Sasha Levin
2024-10-04T18:23:55Z

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: Sasha Levin <sashal@kernel.org>
---
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 a024aecb76dc3..de1736f834e6b 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)
@@ -277,7 +281,10 @@ uvc_v4l2_try_format(struct file *file, void *fh, struct v4l2_format *fmt)
fmt->fmt.pix.height = uframe->frame.w_height;
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.field = V4L2_FIELD_NONE;
fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
@@ -389,6 +396,9 @@ 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;
--
2.43.0