From: Jordan Crouse <jcrouse@codeaurora.org>
Date: Tue, 19 Feb 2019 18:40:19 +0000 (-0700)
Subject: drm/msm: Truncate the buffer object name if the copy from user failed
X-Git-Tag: v5.1-rc1~117^2~5^2
X-Git-Url: https://asedeno.scripts.mit.edu/gitweb/?a=commitdiff_plain;h=860433ed2a55dcd18f36c61b3c4fdb12dc76c869;p=linux.git

drm/msm: Truncate the buffer object name if the copy from user failed

(Resend since there was a compile error that I forgot to commit before sending)

If there is a error while doing a copy_from_user() for MSM_INFO_SET_NAME
make sure to truncate the object name so that there isn't a chance that
we'll have random data in the string.

This is on top of [1] reported and fixed by Dan Carpenter.

[1] https://patchwork.freedesktop.org/series/56656/

Fixes: f05c83e77460 ("drm/msm: add uapi to get/set debug name")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jordan Crouse <jcrouse@codeaurora.org>
Signed-off-by: Rob Clark <robdclark@gmail.com>
---

diff --git a/drivers/gpu/drm/msm/msm_drv.c b/drivers/gpu/drm/msm/msm_drv.c
index 87eae44a1006..906b2bb79f6a 100644
--- a/drivers/gpu/drm/msm/msm_drv.c
+++ b/drivers/gpu/drm/msm/msm_drv.c
@@ -852,8 +852,11 @@ static int msm_ioctl_gem_info(struct drm_device *dev, void *data,
 			break;
 		}
 		if (copy_from_user(msm_obj->name, u64_to_user_ptr(args->value),
-				   args->len))
+				   args->len)) {
+			msm_obj->name[0] = '\0';
 			ret = -EFAULT;
+			break;
+		}
 		msm_obj->name[args->len] = '\0';
 		for (i = 0; i < args->len; i++) {
 			if (!isprint(msm_obj->name[i])) {