drm/edid: Fix a missing-check bug in drm_load_edid_firmware()

In drm_load_edid_firmware(), fwstr is allocated by kstrdup(). And fwstr
is dereferenced in the following codes. However, memory allocation
functions such as kstrdup() may fail and returns NULL. Dereferencing
this null pointer may cause the kernel go wrong. Thus we should check
this kstrdup() operation.
Further, if kstrdup() returns NULL, we should return ERR_PTR(-ENOMEM) to
the caller site.

Signed-off-by: Gen Zhang <blackgod016574@gmail.com>
Reviewed-by: Jani Nikula <jani.nikula@intel.com>
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20190524023222.GA5302@zhanggen-UX430UQ
This commit is contained in:
Gen Zhang 2019-05-24 10:32:22 +08:00 committed by Jani Nikula
parent 5fc537bfd0
commit 9f1f1a2dab

View File

@ -293,6 +293,8 @@ struct edid *drm_load_edid_firmware(struct drm_connector *connector)
* the last one found one as a fallback.
*/
fwstr = kstrdup(edid_firmware, GFP_KERNEL);
if (!fwstr)
return ERR_PTR(-ENOMEM);
edidstr = fwstr;
while ((edidname = strsep(&edidstr, ","))) {