From: Xu Kuohai <xukuo...@huawei.com>

To be consistent with most LSM hooks, convert the return value of
hook inode_copy_up_xattr to 0 or a negative error code.

Before:
- Hook inode_copy_up_xattr returns 0 when accepting xattr, 1 when
  discarding xattr, -EOPNOTSUPP if it does not know xattr, or any
  other negative error code otherwise.

After:
- Hook inode_copy_up_xattr returns 0 when accepting xattr, *-ECANCELED*
  when discarding xattr, -EOPNOTSUPP if it does not know xattr, or
  any other negative error code otherwise.

Signed-off-by: Xu Kuohai <xukuo...@huawei.com>
---
 fs/overlayfs/copy_up.c            |  6 +++---
 security/integrity/evm/evm_main.c |  2 +-
 security/security.c               | 12 ++++++------
 security/selinux/hooks.c          |  4 ++--
 security/smack/smack_lsm.c        |  6 +++---
 5 files changed, 15 insertions(+), 15 deletions(-)

diff --git a/fs/overlayfs/copy_up.c b/fs/overlayfs/copy_up.c
index a5ef2005a2cc..337a5be99ac9 100644
--- a/fs/overlayfs/copy_up.c
+++ b/fs/overlayfs/copy_up.c
@@ -115,12 +115,12 @@ int ovl_copy_xattr(struct super_block *sb, const struct 
path *oldpath, struct de
                        continue;
 
                error = security_inode_copy_up_xattr(old, name);
-               if (error < 0 && error != -EOPNOTSUPP)
-                       break;
-               if (error == 1) {
+               if (error == -ECANCELED) {
                        error = 0;
                        continue; /* Discard */
                }
+               if (error < 0 && error != -EOPNOTSUPP)
+                       break;
 
                if (is_posix_acl_xattr(name)) {
                        error = ovl_copy_acl(OVL_FS(sb), oldpath, new, name);
diff --git a/security/integrity/evm/evm_main.c 
b/security/integrity/evm/evm_main.c
index 62fe66dd53ce..6924ed508ebd 100644
--- a/security/integrity/evm/evm_main.c
+++ b/security/integrity/evm/evm_main.c
@@ -1000,7 +1000,7 @@ static int evm_inode_copy_up_xattr(struct dentry *src, 
const char *name)
        case EVM_XATTR_HMAC:
        case EVM_IMA_XATTR_DIGSIG:
        default:
-               rc = 1; /* discard */
+               rc = -ECANCELED; /* discard */
        }
 
        kfree(xattr_data);
diff --git a/security/security.c b/security/security.c
index 26eea8f4cd74..12215ca286af 100644
--- a/security/security.c
+++ b/security/security.c
@@ -2675,18 +2675,18 @@ EXPORT_SYMBOL(security_inode_copy_up);
  * lower layer to the union/overlay layer.   The caller is responsible for
  * reading and writing the xattrs, this hook is merely a filter.
  *
- * Return: Returns 0 to accept the xattr, 1 to discard the xattr, -EOPNOTSUPP
- *         if the security module does not know about attribute, or a negative
- *         error code to abort the copy up.
+ * Return: Returns 0 to accept the xattr, -ECANCELED to discard the xattr,
+ *         -EOPNOTSUPP if the security module does not know about attribute,
+ *         or a negative error code to abort the copy up.
  */
 int security_inode_copy_up_xattr(struct dentry *src, const char *name)
 {
        int rc;
 
        /*
-        * The implementation can return 0 (accept the xattr), 1 (discard the
-        * xattr), -EOPNOTSUPP if it does not know anything about the xattr or
-        * any other error code in case of an error.
+        * The implementation can return 0 (accept the xattr), -ECANCELED
+        * (discard the xattr), -EOPNOTSUPP if it does not know anything
+        *  about the xattr or any other error code in case of an error.
         */
        rc = call_int_hook(inode_copy_up_xattr, src, name);
        if (rc != LSM_RET_DEFAULT(inode_copy_up_xattr))
diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index 5dedd3917d57..f9a6637dfd78 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3528,8 +3528,8 @@ static int selinux_inode_copy_up_xattr(struct dentry 
*dentry, const char *name)
         * xattrs up.  Instead, filter out SELinux-related xattrs following
         * policy load.
         */
-       if (selinux_initialized() && strcmp(name, XATTR_NAME_SELINUX) == 0)
-               return 1; /* Discard */
+       if (selinux_initialized() && !strcmp(name, XATTR_NAME_SELINUX))
+               return -ECANCELED; /* Discard */
        /*
         * Any other attribute apart from SELINUX is not claimed, supported
         * by selinux.
diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c
index 6f73906bf7ea..ae8f1c2d0ca6 100644
--- a/security/smack/smack_lsm.c
+++ b/security/smack/smack_lsm.c
@@ -4893,10 +4893,10 @@ static int smack_inode_copy_up(struct dentry *dentry, 
struct cred **new)
 static int smack_inode_copy_up_xattr(struct dentry *src, const char *name)
 {
        /*
-        * Return 1 if this is the smack access Smack attribute.
+        * Return -ECANCELED if this is the smack access Smack attribute.
         */
-       if (strcmp(name, XATTR_NAME_SMACK) == 0)
-               return 1;
+       if (!strcmp(name, XATTR_NAME_SMACK))
+               return -ECANCELED;
 
        return -EOPNOTSUPP;
 }
-- 
2.30.2


Reply via email to