linux-ext4 - [PATCH v2 4/9] ext4: don't call fscrypt_get_encryption_info() from dx_show

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Date:   Wed,  2 Dec 2020 18:20:36 -0800
From:   Eric Biggers <ebiggers@...nel.org>
To:     linux-fscrypt@...r.kernel.org
Cc:     linux-ext4@...r.kernel.org, linux-f2fs-devel@...ts.sourceforge.net,
        linux-mtd@...ts.infradead.org, linux-fsdevel@...r.kernel.org,
        Andreas Dilger <adilger@...ger.ca>
Subject: [PATCH v2 4/9] ext4: don't call fscrypt_get_encryption_info() from dx_show_leaf()

From: Eric Biggers <ebiggers@...gle.com>

The call to fscrypt_get_encryption_info() in dx_show_leaf() is too low
in the call tree; fscrypt_get_encryption_info() should have already been
called when starting the directory operation.  And indeed, it already
is.  Moreover, the encryption key is guaranteed to already be available
because dx_show_leaf() is only called when adding a new directory entry.

And even if the key wasn't available, dx_show_leaf() uses
fscrypt_fname_disk_to_usr() which knows how to create a no-key name.

So for the above reasons, and because it would be desirable to stop
exporting fscrypt_get_encryption_info() directly to filesystems, remove
the call to fscrypt_get_encryption_info() from dx_show_leaf().

Reviewed-by: Andreas Dilger <adilger@...ger.ca>
Signed-off-by: Eric Biggers <ebiggers@...gle.com>
---
 fs/ext4/namei.c | 8 +-------
 1 file changed, 1 insertion(+), 7 deletions(-)

diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 793fc7db9d28f..7b31aea3e0253 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -643,13 +643,7 @@ static struct stats dx_show_leaf(struct inode *dir,

 				name  = de->name;
 				len = de->name_len;
-				if (IS_ENCRYPTED(dir))
-					res = fscrypt_get_encryption_info(dir);
-				if (res) {
-					printk(KERN_WARNING "Error setting up"
-					       " fname crypto: %d\n", res);
-				}
-				if (!fscrypt_has_encryption_key(dir)) {
+				if (!IS_ENCRYPTED(dir)) {
 					/* Directory is not encrypted */
 					ext4fs_dirhash(dir, de->name,
 						de->name_len, &h);
-- 
2.29.2