[PATCH] kill nameidata passing to permission(), rename to inode_permission()

[safe/jmp/linux-2.6] / fs / xattr.c

diff --git a/fs/xattr.c b/fs/xattr.c
index 3864613..b96222e 100644 (file)
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -9,9 +9,9 @@
  */
 #include <linux/fs.h>
 #include <linux/slab.h>
-#include <linux/smp_lock.h>
 #include <linux/file.h>
 #include <linux/xattr.h>
+#include <linux/mount.h>
 #include <linux/namei.h>
 #include <linux/security.h>
 #include <linux/syscalls.h>
@@ -33,8 +33,6 @@ xattr_permission(struct inode *inode, const char *name, int mask)
         * filesystem  or on an immutable / append-only inode.
         */
        if (mask & MAY_WRITE) {
-               if (IS_RDONLY(inode))
-                       return -EROFS;
                if (IS_IMMUTABLE(inode) || IS_APPEND(inode))
                        return -EPERM;
        }
@@ -61,16 +59,15 @@ xattr_permission(struct inode *inode, const char *name, int mask)
                if (!S_ISREG(inode->i_mode) && !S_ISDIR(inode->i_mode))
                        return -EPERM;
                if (S_ISDIR(inode->i_mode) && (inode->i_mode & S_ISVTX) &&
-                   (mask & MAY_WRITE) && (current->fsuid != inode->i_uid) &&
-                   !capable(CAP_FOWNER))
+                   (mask & MAY_WRITE) && !is_owner_or_cap(inode))
                        return -EPERM;
        }
 
-       return permission(inode, mask, NULL);
+       return inode_permission(inode, mask);
 }
 
 int
-vfs_setxattr(struct dentry *dentry, char *name, void *value,
+vfs_setxattr(struct dentry *dentry, const char *name, const void *value,
                size_t size, int flags)
 {
        struct inode *inode = dentry->d_inode;
@@ -107,7 +104,34 @@ out:
 EXPORT_SYMBOL_GPL(vfs_setxattr);
 
 ssize_t
-vfs_getxattr(struct dentry *dentry, char *name, void *value, size_t size)
+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, const char *name, void *value, size_t size)
 {
        struct inode *inode = dentry->d_inode;
        int error;
@@ -120,23 +144,23 @@ 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;
 }
@@ -163,7 +187,7 @@ vfs_listxattr(struct dentry *d, char *list, size_t size)
 EXPORT_SYMBOL_GPL(vfs_listxattr);
 
 int
-vfs_removexattr(struct dentry *dentry, char *name)
+vfs_removexattr(struct dentry *dentry, const char *name)
 {
        struct inode *inode = dentry->d_inode;
        int error;
@@ -194,7 +218,7 @@ EXPORT_SYMBOL_GPL(vfs_removexattr);
  * Extended attribute SET operations
  */
 static long
-setxattr(struct dentry *d, char __user *name, void __user *value,
+setxattr(struct dentry *d, const char __user *name, const void __user *value,
         size_t size, int flags)
 {
        int error;
@@ -228,8 +252,8 @@ setxattr(struct dentry *d, char __user *name, void __user *value,
 }
 
 asmlinkage long
-sys_setxattr(char __user *path, char __user *name, void __user *value,
-            size_t size, int flags)
+sys_setxattr(const char __user *path, const char __user *name,
+            const void __user *value, size_t size, int flags)
 {
        struct nameidata nd;
        int error;
@@ -237,14 +261,18 @@ 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 = mnt_want_write(nd.path.mnt);
+       if (!error) {
+               error = setxattr(nd.path.dentry, name, value, size, flags);
+               mnt_drop_write(nd.path.mnt);
+       }
+       path_put(&nd.path);
        return error;
 }
 
 asmlinkage long
-sys_lsetxattr(char __user *path, char __user *name, void __user *value,
-             size_t size, int flags)
+sys_lsetxattr(const char __user *path, const char __user *name,
+             const void __user *value, size_t size, int flags)
 {
        struct nameidata nd;
        int error;
@@ -252,13 +280,17 @@ 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 = mnt_want_write(nd.path.mnt);
+       if (!error) {
+               error = setxattr(nd.path.dentry, name, value, size, flags);
+               mnt_drop_write(nd.path.mnt);
+       }
+       path_put(&nd.path);
        return error;
 }
 
 asmlinkage long
-sys_fsetxattr(int fd, char __user *name, void __user *value,
+sys_fsetxattr(int fd, const char __user *name, const void __user *value,
              size_t size, int flags)
 {
        struct file *f;
@@ -269,8 +301,12 @@ 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);
-       error = setxattr(dentry, name, value, size, flags);
+       audit_inode(NULL, dentry);
+       error = mnt_want_write(f->f_path.mnt);
+       if (!error) {
+               error = setxattr(dentry, name, value, size, flags);
+               mnt_drop_write(f->f_path.mnt);
+       }
        fput(f);
        return error;
 }
@@ -279,7 +315,8 @@ sys_fsetxattr(int fd, char __user *name, void __user *value,
  * Extended attribute GET operations
  */
 static ssize_t
-getxattr(struct dentry *d, char __user *name, void __user *value, size_t size)
+getxattr(struct dentry *d, const char __user *name, void __user *value,
+        size_t size)
 {
        ssize_t error;
        void *kvalue = NULL;
@@ -313,8 +350,8 @@ getxattr(struct dentry *d, char __user *name, void __user *value, size_t size)
 }
 
 asmlinkage ssize_t
-sys_getxattr(char __user *path, char __user *name, void __user *value,
-            size_t size)
+sys_getxattr(const char __user *path, const char __user *name,
+            void __user *value, size_t size)
 {
        struct nameidata nd;
        ssize_t error;
@@ -322,13 +359,13 @@ 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;
 }
 
 asmlinkage ssize_t
-sys_lgetxattr(char __user *path, char __user *name, void __user *value,
+sys_lgetxattr(const char __user *path, const char __user *name, void __user *value,
              size_t size)
 {
        struct nameidata nd;
@@ -337,13 +374,13 @@ 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;
 }
 
 asmlinkage ssize_t
-sys_fgetxattr(int fd, char __user *name, void __user *value, size_t size)
+sys_fgetxattr(int fd, const char __user *name, void __user *value, size_t size)
 {
        struct file *f;
        ssize_t error = -EBADF;
@@ -351,6 +388,7 @@ 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);
        error = getxattr(f->f_path.dentry, name, value, size);
        fput(f);
        return error;
@@ -387,7 +425,7 @@ listxattr(struct dentry *d, char __user *list, size_t size)
 }
 
 asmlinkage ssize_t
-sys_listxattr(char __user *path, char __user *list, size_t size)
+sys_listxattr(const char __user *path, char __user *list, size_t size)
 {
        struct nameidata nd;
        ssize_t error;
@@ -395,13 +433,13 @@ 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;
 }
 
 asmlinkage ssize_t
-sys_llistxattr(char __user *path, char __user *list, size_t size)
+sys_llistxattr(const char __user *path, char __user *list, size_t size)
 {
        struct nameidata nd;
        ssize_t error;
@@ -409,8 +447,8 @@ 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;
 }
 
@@ -423,6 +461,7 @@ sys_flistxattr(int fd, char __user *list, size_t size)
        f = fget(fd);
        if (!f)
                return error;
+       audit_inode(NULL, f->f_path.dentry);
        error = listxattr(f->f_path.dentry, list, size);
        fput(f);
        return error;
@@ -432,7 +471,7 @@ sys_flistxattr(int fd, char __user *list, size_t size)
  * Extended attribute REMOVE operations
  */
 static long
-removexattr(struct dentry *d, char __user *name)
+removexattr(struct dentry *d, const char __user *name)
 {
        int error;
        char kname[XATTR_NAME_MAX + 1];
@@ -447,7 +486,7 @@ removexattr(struct dentry *d, char __user *name)
 }
 
 asmlinkage long
-sys_removexattr(char __user *path, char __user *name)
+sys_removexattr(const char __user *path, const char __user *name)
 {
        struct nameidata nd;
        int error;
@@ -455,13 +494,17 @@ 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 = mnt_want_write(nd.path.mnt);
+       if (!error) {
+               error = removexattr(nd.path.dentry, name);
+               mnt_drop_write(nd.path.mnt);
+       }
+       path_put(&nd.path);
        return error;
 }
 
 asmlinkage long
-sys_lremovexattr(char __user *path, char __user *name)
+sys_lremovexattr(const char __user *path, const char __user *name)
 {
        struct nameidata nd;
        int error;
@@ -469,13 +512,17 @@ 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 = mnt_want_write(nd.path.mnt);
+       if (!error) {
+               error = removexattr(nd.path.dentry, name);
+               mnt_drop_write(nd.path.mnt);
+       }
+       path_put(&nd.path);
        return error;
 }
 
 asmlinkage long
-sys_fremovexattr(int fd, char __user *name)
+sys_fremovexattr(int fd, const char __user *name)
 {
        struct file *f;
        struct dentry *dentry;
@@ -485,8 +532,12 @@ sys_fremovexattr(int fd, char __user *name)
        if (!f)
                return error;
        dentry = f->f_path.dentry;
-       audit_inode(NULL, dentry->d_inode);
-       error = removexattr(dentry, name);
+       audit_inode(NULL, dentry);
+       error = mnt_want_write(f->f_path.mnt);
+       if (!error) {
+               error = removexattr(dentry, name);
+               mnt_drop_write(f->f_path.mnt);
+       }
        fput(f);
        return error;
 }