9p: move xattr-related structs to .rodata

This makes it harder for accidental or malicious changes to
v9fs_xattr_user_handler, v9fs_xattr_trusted_handler,
v9fs_xattr_security_handler, or v9fs_xattr_handlers at runtime.

Cc: Eric Van Hensbergen <ericvh@kernel.org>
Cc: Latchesar Ionkov <lucho@ionkov.net>
Cc: Dominique Martinet <asmadeus@codewreck.org>
Cc: Christian Schoenebeck <linux_oss@crudebyte.com>
Cc: v9fs@lists.linux.dev
Signed-off-by: Wedson Almeida Filho <walmeida@microsoft.com>
Link: https://lore.kernel.org/r/20230930050033.41174-4-wedsonaf@gmail.com
Acked-by: Dominique Martinet <asmadeus@codewreck.org>
Reviewed-by: Christian Schoenebeck <linux_oss@crudebyte.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>

diff --git a/fs/9p/xattr.c b/fs/9p/xattr.c
index e00cf81..053d1ce 100644 (file)
--- a/fs/9p/xattr.c
+++ b/fs/9p/xattr.c
@@ -162,27 +162,27 @@ static int v9fs_xattr_handler_set(const struct xattr_handler *handler,
        return v9fs_xattr_set(dentry, full_name, value, size, flags);
 }
 
-static struct xattr_handler v9fs_xattr_user_handler = {
+static const struct xattr_handler v9fs_xattr_user_handler = {
        .prefix = XATTR_USER_PREFIX,
        .get    = v9fs_xattr_handler_get,
        .set    = v9fs_xattr_handler_set,
 };
 
-static struct xattr_handler v9fs_xattr_trusted_handler = {
+static const struct xattr_handler v9fs_xattr_trusted_handler = {
        .prefix = XATTR_TRUSTED_PREFIX,
        .get    = v9fs_xattr_handler_get,
        .set    = v9fs_xattr_handler_set,
 };
 
 #ifdef CONFIG_9P_FS_SECURITY
-static struct xattr_handler v9fs_xattr_security_handler = {
+static const struct xattr_handler v9fs_xattr_security_handler = {
        .prefix = XATTR_SECURITY_PREFIX,
        .get    = v9fs_xattr_handler_get,
        .set    = v9fs_xattr_handler_set,
 };
 #endif
 
-const struct xattr_handler *v9fs_xattr_handlers[] = {
+const struct xattr_handler * const v9fs_xattr_handlers[] = {
        &v9fs_xattr_user_handler,
        &v9fs_xattr_trusted_handler,
 #ifdef CONFIG_9P_FS_SECURITY

diff --git a/fs/9p/xattr.h b/fs/9p/xattr.h
index b5636e5..3ad5a80 100644 (file)
--- a/fs/9p/xattr.h
+++ b/fs/9p/xattr.h
@@ -10,7 +10,7 @@
 #include <net/9p/9p.h>
 #include <net/9p/client.h>
 
-extern const struct xattr_handler *v9fs_xattr_handlers[];
+extern const struct xattr_handler * const v9fs_xattr_handlers[];
 
 ssize_t v9fs_fid_xattr_get(struct p9_fid *fid, const char *name,
                           void *buffer, size_t buffer_size);