Be more careful about marking buffers dirty

[linux.git] / fs / xattr.c

diff --git a/fs/xattr.c b/fs/xattr.c
index a44fd92caca31c72aba82e61ec6b321d7ebf5a7d..3acab16154608724f5558458eea5cac2a00b0b5a 100644 (file)
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -104,6 +104,33 @@ out:
 }
 EXPORT_SYMBOL_GPL(vfs_setxattr);
 
+ssize_t
+xattr_getsecurity(struct inode *inode, const char *name, void *value,
+                       size_t size)
+{
+       void *buffer = NULL;
+       ssize_t len;
+
+       if (!value || !size) {
+               len = security_inode_getsecurity(inode, name, &buffer, false);
+               goto out_noalloc;
+       }
+
+       len = security_inode_getsecurity(inode, name, &buffer, true);
+       if (len < 0)
+               return len;
+       if (size < len) {
+               len = -ERANGE;
+               goto out;
+       }
+       memcpy(value, buffer, len);
+out:
+       security_release_secctx(buffer, len);
+out_noalloc:
+       return len;
+}
+EXPORT_SYMBOL_GPL(xattr_getsecurity);
+
 ssize_t
 vfs_getxattr(struct dentry *dentry, char *name, void *value, size_t size)
 {
@@ -118,23 +145,23 @@ vfs_getxattr(struct dentry *dentry, char *name, void *value, size_t size)
        if (error)
                return error;
 
-       if (inode->i_op->getxattr)
-               error = inode->i_op->getxattr(dentry, name, value, size);
-       else
-               error = -EOPNOTSUPP;
-
        if (!strncmp(name, XATTR_SECURITY_PREFIX,
                                XATTR_SECURITY_PREFIX_LEN)) {
                const char *suffix = name + XATTR_SECURITY_PREFIX_LEN;
-               int ret = security_inode_getsecurity(inode, suffix, value,
-                                                    size, error);
+               int ret = xattr_getsecurity(inode, suffix, value, size);
                /*
                 * Only overwrite the return value if a security module
                 * is actually active.
                 */
-               if (ret != -EOPNOTSUPP)
-                       error = ret;
+               if (ret == -EOPNOTSUPP)
+                       goto nolsm;
+               return ret;
        }
+nolsm:
+       if (inode->i_op->getxattr)
+               error = inode->i_op->getxattr(dentry, name, value, size);
+       else
+               error = -EOPNOTSUPP;
 
        return error;
 }
@@ -235,8 +262,8 @@ sys_setxattr(char __user *path, char __user *name, void __user *value,
        error = user_path_walk(path, &nd);
        if (error)
                return error;
-       error = setxattr(nd.dentry, name, value, size, flags);
-       path_release(&nd);
+       error = setxattr(nd.path.dentry, name, value, size, flags);
+       path_put(&nd.path);
        return error;
 }
 
@@ -250,8 +277,8 @@ sys_lsetxattr(char __user *path, char __user *name, void __user *value,
        error = user_path_walk_link(path, &nd);
        if (error)
                return error;
-       error = setxattr(nd.dentry, name, value, size, flags);
-       path_release(&nd);
+       error = setxattr(nd.path.dentry, name, value, size, flags);
+       path_put(&nd.path);
        return error;
 }
 
@@ -267,7 +294,7 @@ sys_fsetxattr(int fd, char __user *name, void __user *value,
        if (!f)
                return error;
        dentry = f->f_path.dentry;
-       audit_inode(NULL, dentry->d_inode);
+       audit_inode(NULL, dentry);
        error = setxattr(dentry, name, value, size, flags);
        fput(f);
        return error;
@@ -320,8 +347,8 @@ sys_getxattr(char __user *path, char __user *name, void __user *value,
        error = user_path_walk(path, &nd);
        if (error)
                return error;
-       error = getxattr(nd.dentry, name, value, size);
-       path_release(&nd);
+       error = getxattr(nd.path.dentry, name, value, size);
+       path_put(&nd.path);
        return error;
 }
 
@@ -335,8 +362,8 @@ sys_lgetxattr(char __user *path, char __user *name, void __user *value,
        error = user_path_walk_link(path, &nd);
        if (error)
                return error;
-       error = getxattr(nd.dentry, name, value, size);
-       path_release(&nd);
+       error = getxattr(nd.path.dentry, name, value, size);
+       path_put(&nd.path);
        return error;
 }
 
@@ -349,7 +376,7 @@ sys_fgetxattr(int fd, char __user *name, void __user *value, size_t size)
        f = fget(fd);
        if (!f)
                return error;
-       audit_inode(NULL, f->f_path.dentry->d_inode);
+       audit_inode(NULL, f->f_path.dentry);
        error = getxattr(f->f_path.dentry, name, value, size);
        fput(f);
        return error;
@@ -394,8 +421,8 @@ sys_listxattr(char __user *path, char __user *list, size_t size)
        error = user_path_walk(path, &nd);
        if (error)
                return error;
-       error = listxattr(nd.dentry, list, size);
-       path_release(&nd);
+       error = listxattr(nd.path.dentry, list, size);
+       path_put(&nd.path);
        return error;
 }
 
@@ -408,8 +435,8 @@ sys_llistxattr(char __user *path, char __user *list, size_t size)
        error = user_path_walk_link(path, &nd);
        if (error)
                return error;
-       error = listxattr(nd.dentry, list, size);
-       path_release(&nd);
+       error = listxattr(nd.path.dentry, list, size);
+       path_put(&nd.path);
        return error;
 }
 
@@ -422,7 +449,7 @@ sys_flistxattr(int fd, char __user *list, size_t size)
        f = fget(fd);
        if (!f)
                return error;
-       audit_inode(NULL, f->f_path.dentry->d_inode);
+       audit_inode(NULL, f->f_path.dentry);
        error = listxattr(f->f_path.dentry, list, size);
        fput(f);
        return error;
@@ -455,8 +482,8 @@ sys_removexattr(char __user *path, char __user *name)
        error = user_path_walk(path, &nd);
        if (error)
                return error;
-       error = removexattr(nd.dentry, name);
-       path_release(&nd);
+       error = removexattr(nd.path.dentry, name);
+       path_put(&nd.path);
        return error;
 }
 
@@ -469,8 +496,8 @@ sys_lremovexattr(char __user *path, char __user *name)
        error = user_path_walk_link(path, &nd);
        if (error)
                return error;
-       error = removexattr(nd.dentry, name);
-       path_release(&nd);
+       error = removexattr(nd.path.dentry, name);
+       path_put(&nd.path);
        return error;
 }
 
@@ -485,7 +512,7 @@ sys_fremovexattr(int fd, char __user *name)
        if (!f)
                return error;
        dentry = f->f_path.dentry;
-       audit_inode(NULL, dentry->d_inode);
+       audit_inode(NULL, dentry);
        error = removexattr(dentry, name);
        fput(f);
        return error;