Linux 3.8 compat: Use kuid_t/kgid_t when required

When CONFIG_UIDGID_STRICT_TYPE_CHECKS is enabled uid_t/git_t are
replaced by kuid_t/kgid_t, which are structures instead of integral
types. This causes any code that uses an integral type to fail to build.
The User Namespace functionality introduced in Linux 3.8 requires
CONFIG_UIDGID_STRICT_TYPE_CHECKS, so we could not build against any
kernel that supported it.

We resolve this by converting between the new kuid_t/kgid_t structures
and the original uid_t/gid_t types.

Original-patch-by: DHE
Rewrite-by: Richard Yao <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Closes #260

1 files changed, 16 insertions, 12 deletions

diff --git a/module/spl/spl-cred.c b/module/spl/spl-cred.c
index e669cbf5d..0ed65725e 100644
--- a/module/spl/spl-cred.c
+++ b/module/spl/spl-cred.c
@@ -38,7 +38,11 @@
 #else
 /* Implementation from 2.6.30 kernel */
 static int
+#ifdef HAVE_KUIDGID_T
+cr_groups_search(const struct group_info *group_info, kgid_t grp)
+#else
 cr_groups_search(const struct group_info *group_info, gid_t grp)
+#endif
 {
 	unsigned int left, right;
 
@@ -49,7 +53,7 @@ cr_groups_search(const struct group_info *group_info, gid_t grp)
 	right = group_info->ngroups;
 	while (left < right) {
 		unsigned int mid = (left+right)/2;
-		int cmp = grp - GROUP_AT(group_info, mid);
+		int cmp = KGID_TO_SGID(grp) - KGID_TO_SGID(GROUP_AT(group_info, mid));
 		if (cmp > 0)
 			left = mid + 1;
 		else if (cmp < 0)
@@ -110,7 +114,7 @@ crgetgroups(const cred_t *cr)
 	gid_t *gids;
 
 	gi = get_group_info(cr->group_info);
-	gids = gi->blocks[0];
+	gids = KGIDP_TO_SGIDP(gi->blocks[0]);
 	put_group_info(gi);
 
 	return gids;
@@ -124,7 +128,7 @@ groupmember(gid_t gid, const cred_t *cr)
 	int rc;
 
 	gi = get_group_info(cr->group_info);
-	rc = cr_groups_search(cr->group_info, gid);
+	rc = cr_groups_search(cr->group_info, SGID_TO_KGID(gid));
 	put_group_info(gi);
 
 	return rc;
@@ -180,7 +184,7 @@ crgetgroups(const cred_t *cr)
 		task_lock((struct task_struct *)cr);
 
 	get_group_info(cr->group_info);
-	gids = cr->group_info->blocks[0];
+	gids = KGID_TO_SGID(cr->group_info->blocks[0]);
 	put_group_info(cr->group_info);
 
 	if (lock)
@@ -215,56 +219,56 @@ groupmember(gid_t gid, const cred_t *cr)
 uid_t
 crgetuid(const cred_t *cr)
 {
-	return cr->euid;
+	return KUID_TO_SUID(cr->euid);
 }
 
 /* Return the real user id */
 uid_t
 crgetruid(const cred_t *cr)
 {
-	return cr->uid;
+	return KUID_TO_SUID(cr->uid);
 }
 
 /* Return the saved user id */
 uid_t
 crgetsuid(const cred_t *cr)
 {
-	return cr->suid;
+	return KUID_TO_SUID(cr->suid);
 }
 
 /* Return the filesystem user id */
 uid_t
 crgetfsuid(const cred_t *cr)
 {
-	return cr->fsuid;
+	return KUID_TO_SUID(cr->fsuid);
 }
 
 /* Return the effective group id */
 gid_t
 crgetgid(const cred_t *cr)
 {
-	return cr->egid;
+	return KGID_TO_SGID(cr->egid);
 }
 
 /* Return the real group id */
 gid_t
 crgetrgid(const cred_t *cr)
 {
-	return cr->gid;
+	return KGID_TO_SGID(cr->gid);
 }
 
 /* Return the saved group id */
 gid_t
 crgetsgid(const cred_t *cr)
 {
-	return cr->sgid;
+	return KGID_TO_SGID(cr->sgid);
 }
 
 /* Return the filesystem group id */
 gid_t
 crgetfsgid(const cred_t *cr)
 {
-	return cr->fsgid;
+	return KGID_TO_SGID(cr->fsgid);
 }
 
 EXPORT_SYMBOL(crhold);