Linux 4.5 compat: Use xattr_handler->name for acl

Linux 4.5 added member "name" to xattr_handler. xattr_handler which matches to
whole name rather than prefix should use "name" instead of "prefix".
Otherwise, kernel will return with EINVAL when it tries to resolve handlers.

Also, we remove the strcmp checks when xattr_handler has name, because
xattr_resolve_name will do the check for us.

Signed-off-by: Chunwei Chen <[email protected]>
Signed-off-by: Brian Behlendorf <[email protected]>
Closes #4549
Closes #4537

1 files changed, 44 insertions, 20 deletions

diff --git a/module/zfs/zpl_xattr.c b/module/zfs/zpl_xattr.c
index e8623384c..23c63a587 100644
--- a/module/zfs/zpl_xattr.c
+++ b/module/zfs/zpl_xattr.c
@@ -688,10 +688,11 @@ __zpl_xattr_user_get(struct inode *ip, const char *name,
 {
 	char *xattr_name;
 	int error;
-
+	/* xattr_resolve_name will do this for us if this is defined */
+#ifndef HAVE_XATTR_HANDLER_NAME
 	if (strcmp(name, "") == 0)
 		return (-EINVAL);
-
+#endif
 	if (!(ITOZSB(ip)->z_flags & ZSB_XATTR))
 		return (-EOPNOTSUPP);
 
@@ -709,10 +710,11 @@ __zpl_xattr_user_set(struct inode *ip, const char *name,
 {
 	char *xattr_name;
 	int error;
-
+	/* xattr_resolve_name will do this for us if this is defined */
+#ifndef HAVE_XATTR_HANDLER_NAME
 	if (strcmp(name, "") == 0)
 		return (-EINVAL);
-
+#endif
 	if (!(ITOZSB(ip)->z_flags & ZSB_XATTR))
 		return (-EOPNOTSUPP);
 
@@ -758,10 +760,11 @@ __zpl_xattr_trusted_get(struct inode *ip, const char *name,
 
 	if (!capable(CAP_SYS_ADMIN))
 		return (-EACCES);
-
+	/* xattr_resolve_name will do this for us if this is defined */
+#ifndef HAVE_XATTR_HANDLER_NAME
 	if (strcmp(name, "") == 0)
 		return (-EINVAL);
-
+#endif
 	xattr_name = kmem_asprintf("%s%s", XATTR_TRUSTED_PREFIX, name);
 	error = zpl_xattr_get(ip, xattr_name, value, size);
 	strfree(xattr_name);
@@ -779,10 +782,11 @@ __zpl_xattr_trusted_set(struct inode *ip, const char *name,
 
 	if (!capable(CAP_SYS_ADMIN))
 		return (-EACCES);
-
+	/* xattr_resolve_name will do this for us if this is defined */
+#ifndef HAVE_XATTR_HANDLER_NAME
 	if (strcmp(name, "") == 0)
 		return (-EINVAL);
-
+#endif
 	xattr_name = kmem_asprintf("%s%s", XATTR_TRUSTED_PREFIX, name);
 	error = zpl_xattr_set(ip, xattr_name, value, size, flags);
 	strfree(xattr_name);
@@ -825,10 +829,11 @@ __zpl_xattr_security_get(struct inode *ip, const char *name,
 {
 	char *xattr_name;
 	int error;
-
+	/* xattr_resolve_name will do this for us if this is defined */
+#ifndef HAVE_XATTR_HANDLER_NAME
 	if (strcmp(name, "") == 0)
 		return (-EINVAL);
-
+#endif
 	xattr_name = kmem_asprintf("%s%s", XATTR_SECURITY_PREFIX, name);
 	error = zpl_xattr_get(ip, xattr_name, value, size);
 	strfree(xattr_name);
@@ -843,10 +848,11 @@ __zpl_xattr_security_set(struct inode *ip, const char *name,
 {
 	char *xattr_name;
 	int error;
-
+	/* xattr_resolve_name will do this for us if this is defined */
+#ifndef HAVE_XATTR_HANDLER_NAME
 	if (strcmp(name, "") == 0)
 		return (-EINVAL);
-
+#endif
 	xattr_name = kmem_asprintf("%s%s", XATTR_SECURITY_PREFIX, name);
 	error = zpl_xattr_set(ip, xattr_name, value, size, flags);
 	strfree(xattr_name);
@@ -1212,10 +1218,11 @@ __zpl_xattr_acl_get_access(struct inode *ip, const char *name,
 	struct posix_acl *acl;
 	int type = ACL_TYPE_ACCESS;
 	int error;
-
+	/* xattr_resolve_name will do this for us if this is defined */
+#ifndef HAVE_XATTR_HANDLER_NAME
 	if (strcmp(name, "") != 0)
 		return (-EINVAL);
-
+#endif
 	if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
 		return (-EOPNOTSUPP);
 
@@ -1239,10 +1246,11 @@ __zpl_xattr_acl_get_default(struct inode *ip, const char *name,
 	struct posix_acl *acl;
 	int type = ACL_TYPE_DEFAULT;
 	int error;
-
+	/* xattr_resolve_name will do this for us if this is defined */
+#ifndef HAVE_XATTR_HANDLER_NAME
 	if (strcmp(name, "") != 0)
 		return (-EINVAL);
-
+#endif
 	if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
 		return (-EOPNOTSUPP);
 
@@ -1266,10 +1274,11 @@ __zpl_xattr_acl_set_access(struct inode *ip, const char *name,
 	struct posix_acl *acl;
 	int type = ACL_TYPE_ACCESS;
 	int error = 0;
-
+	/* xattr_resolve_name will do this for us if this is defined */
+#ifndef HAVE_XATTR_HANDLER_NAME
 	if (strcmp(name, "") != 0)
 		return (-EINVAL);
-
+#endif
 	if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
 		return (-EOPNOTSUPP);
 
@@ -1305,10 +1314,11 @@ __zpl_xattr_acl_set_default(struct inode *ip, const char *name,
 	struct posix_acl *acl;
 	int type = ACL_TYPE_DEFAULT;
 	int error = 0;
-
+	/* xattr_resolve_name will do this for us if this is defined */
+#ifndef HAVE_XATTR_HANDLER_NAME
 	if (strcmp(name, "") != 0)
 		return (-EINVAL);
-
+#endif
 	if (ITOZSB(ip)->z_acl_type != ZFS_ACLTYPE_POSIXACL)
 		return (-EOPNOTSUPP);
 
@@ -1339,10 +1349,17 @@ ZPL_XATTR_SET_WRAPPER(zpl_xattr_acl_set_default);
 
 /*
  * ACL access xattr namespace handlers.
+ *
+ * Use .name instead of .prefix when available. xattr_resolve_name will match
+ * whole name and reject anything that has .name only as prefix.
  */
 xattr_handler_t zpl_xattr_acl_access_handler =
 {
+#ifdef HAVE_XATTR_HANDLER_NAME
+	.name	= XATTR_NAME_POSIX_ACL_ACCESS,
+#else
 	.prefix	= XATTR_NAME_POSIX_ACL_ACCESS,
+#endif
 	.list	= zpl_xattr_acl_list_access,
 	.get	= zpl_xattr_acl_get_access,
 	.set	= zpl_xattr_acl_set_access,
@@ -1355,10 +1372,17 @@ xattr_handler_t zpl_xattr_acl_access_handler =
 
 /*
  * ACL default xattr namespace handlers.
+ *
+ * Use .name instead of .prefix when available. xattr_resolve_name will match
+ * whole name and reject anything that has .name only as prefix.
  */
 xattr_handler_t zpl_xattr_acl_default_handler =
 {
+#ifdef HAVE_XATTR_HANDLER_NAME
+	.name	= XATTR_NAME_POSIX_ACL_DEFAULT,
+#else
 	.prefix	= XATTR_NAME_POSIX_ACL_DEFAULT,
+#endif
 	.list	= zpl_xattr_acl_list_default,
 	.get	= zpl_xattr_acl_get_default,
 	.set	= zpl_xattr_acl_set_default,