diff mbox series

[v2,3/5] drm/i915/gem: Replace user_access_begin by user_write_access_begin

Message ID ebf1250b6d4f351469fb339e5399d8b92aa8a1c1.1585898438.git.christophe.leroy@c-s.fr (mailing list archive)
State New, archived
Headers show
Series [v2,1/5] uaccess: Add user_read_access_begin/end and user_write_access_begin/end | expand

Commit Message

Christophe Leroy April 3, 2020, 7:20 a.m. UTC 
When i915_gem_execbuffer2_ioctl() is using user_access_begin(),
that's only to perform unsafe_put_user() so use
user_write_access_begin() in order to only open write access.

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Kees Cook <keescook@chromium.org>
---
v2: Rebased (one part of the patch flies away)
---
 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

Comments

Michael Ellerman May 29, 2020, 4:20 a.m. UTC | #1 
On Fri, 2020-04-03 at 07:20:52 UTC, Christophe Leroy wrote:
> When i915_gem_execbuffer2_ioctl() is using user_access_begin(),
> that's only to perform unsafe_put_user() so use
> user_write_access_begin() in order to only open write access.
> 
> Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
> Reviewed-by: Kees Cook <keescook@chromium.org>

Applied to powerpc topic/uaccess, thanks.

https://git.kernel.org/powerpc/c/b44f687386875b714dae2afa768e73401e45c21c

cheers
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index 36d069504836..b4c903308590 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -2794,7 +2794,8 @@  i915_gem_execbuffer2_ioctl(struct drm_device *dev, void *data,
 		 * And this range already got effectively checked earlier
 		 * when we did the "copy_from_user()" above.
 		 */
-		if (!user_access_begin(user_exec_list, count * sizeof(*user_exec_list)))
+		if (!user_write_access_begin(user_exec_list,
+					     count * sizeof(*user_exec_list)))
 			goto end;
 
 		for (i = 0; i < args->buffer_count; i++) {
@@ -2808,7 +2809,7 @@  i915_gem_execbuffer2_ioctl(struct drm_device *dev, void *data,
 					end_user);
 		}
 end_user:
-		user_access_end();
+		user_write_access_end();
 end:;
 	}