[PATCH RESEND] iov_iter: Use user_read_access_begin() instead of user_access_begin()

[PATCH RESEND] iov_iter: Use user_read_access_begin() instead of user_access_begin()

[Christophe Leroy]

copy_compat_iovec_from_user() only do unsafe_get_user(),
it only requires read access.

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
Resending with mm list in addition

 lib/iov_iter.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/iov_iter.c b/lib/iov_iter.c
index 61228a6c69f8..fd9bd229d51d 100644
--- a/lib/iov_iter.c
+++ b/lib/iov_iter.c
@@ -1932,7 +1932,7 @@ static int copy_compat_iovec_from_user(struct iovec *iov,
 		(const struct compat_iovec __user *)uvec;
 	int ret = -EFAULT, i;
 
-	if (!user_access_begin(uiov, nr_segs * sizeof(*uiov)))
+	if (!user_read_access_begin(uiov, nr_segs * sizeof(*uiov)))
 		return -EFAULT;
 
 	for (i = 0; i < nr_segs; i++) {
@@ -1953,7 +1953,7 @@ static int copy_compat_iovec_from_user(struct iovec *iov,
 
 	ret = 0;
 uaccess_end:
-	user_access_end();
+	user_read_access_end();
 	return ret;
 }
 
-- 
2.25.0

[PATCH RESEND] drm/i915/gem: Use user_write_access_begin() instead of user_access_begin()

[Christophe Leroy]

eb_copy_relocations() only do unsafe_put_user(), it only
requires write access to user.

Use user_write_access_begin() instead of user_access_begin().

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
---
Resending with mm list in addition

 drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
index 5964e67c7d36..f7a7bb45274b 100644
--- a/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
+++ b/drivers/gpu/drm/i915/gem/i915_gem_execbuffer.c
@@ -1907,14 +1907,14 @@ static int eb_copy_relocations(const struct i915_execbuffer *eb)
 		 * happened we would make the mistake of assuming that the
 		 * relocations were valid.
 		 */
-		if (!user_access_begin(urelocs, size))
+		if (!user_write_access_begin(urelocs, size))
 			goto end;
 
 		for (copied = 0; copied < nreloc; copied++)
 			unsafe_put_user(-1,
 					&urelocs[copied].presumed_offset,
 					end_user);
-		user_access_end();
+		user_write_access_end();
 
 		eb->exec[i].relocs_ptr = (uintptr_t)relocs;
 	}
@@ -1922,7 +1922,7 @@ static int eb_copy_relocations(const struct i915_execbuffer *eb)
 	return 0;
 
 end_user:
-	user_access_end();
+	user_write_access_end();
 end:
 	kvfree(relocs);
 	err = -EFAULT;
-- 
2.25.0