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FAILED: patch "[PATCH] ubifs: report correct st_size for encrypted symlinks" failed to apply to 4.19-stable tree

PATCH [email protected] 1 participant 1 message Sep 1, 2021

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Stable branch UBI file system (UBIFS)
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The patch below does not apply to the 4.19-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.

thanks,

greg k-h

------------------ original commit in Linus's tree ------------------

From 064c734986011390b4d111f1a99372b7f26c3850 Mon Sep 17 00:00:00 2001
From: Eric Biggers <[email protected]>
Date: Thu, 1 Jul 2021 23:53:49 -0700
Subject: [PATCH] ubifs: report correct st_size for encrypted symlinks

The stat() family of syscalls report the wrong size for encrypted symlinks, which has caused breakage in several userspace programs.

Fix this by calling fscrypt_symlink_getattr() after ubifs_getattr() for encrypted symlinks. This function computes the correct size by reading and decrypting the symlink target (if it's not already cached).

For more details, see the commit which added fscrypt_symlink_getattr().

Fixes ca7f85be8d6c ("ubifs: Add support for encrypted symlinks")
Cc [email protected]
Link https://lore.kernel.org/r/[email protected] open here
Signed-off-by Eric Biggers <[email protected]>
fs/ubifs/file.c +12 -1
index 2e4e1d159969..5cfa28cd00cd 100644
@@ -1630,6 +1630,17 @@ static const char *ubifs_get_link(struct dentry *dentry,
 	return fscrypt_get_symlink(inode, ui->data, ui->data_len, done);
 }
 
+static int ubifs_symlink_getattr(struct user_namespace *mnt_userns,
+				 const struct path *path, struct kstat *stat,
+				 u32 request_mask, unsigned int query_flags)
+{
+	ubifs_getattr(mnt_userns, path, stat, request_mask, query_flags);
+
+	if (IS_ENCRYPTED(d_inode(path->dentry)))
+		return fscrypt_symlink_getattr(path, stat);
+	return 0;
+}
+
 const struct address_space_operations ubifs_file_address_operations = {
 	.readpage       = ubifs_readpage,
 	.writepage      = ubifs_writepage,

@@ -1655,7 +1666,7 @@ const struct inode_operations ubifs_file_inode_operations = {
 const struct inode_operations ubifs_symlink_inode_operations = {
 	.get_link    = ubifs_get_link,
 	.setattr     = ubifs_setattr,
-	.getattr     = ubifs_getattr,
+	.getattr     = ubifs_symlink_getattr,
 	.listxattr   = ubifs_listxattr,
 	.update_time = ubifs_update_time,
 };