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authorTheodore Ts'o <tytso@mit.edu>2015-05-31 19:34:24 +0200
committerTheodore Ts'o <tytso@mit.edu>2015-05-31 19:34:24 +0200
commit95ea68b4c7105179f507d31f7bf571623373aa0b (patch)
tree5aead7a970083ed83e40f57c7a25323075de792e
parentext4 crypto: use per-inode tfm structure (diff)
downloadlinux-95ea68b4c7105179f507d31f7bf571623373aa0b.tar.xz
linux-95ea68b4c7105179f507d31f7bf571623373aa0b.zip
ext4 crypto: fix memory leaks in ext4_encrypted_zeroout
ext4_encrypted_zeroout() could end up leaking a bio and bounce page. Fortunately it's not used much. While we're fixing things up, refactor out common code into the static function alloc_bounce_page() and fix up error handling if mempool_alloc() fails. Signed-off-by: Theodore Ts'o <tytso@mit.edu>
-rw-r--r--fs/ext4/crypto.c62
1 files changed, 31 insertions, 31 deletions
diff --git a/fs/ext4/crypto.c b/fs/ext4/crypto.c
index c3a9b08309db..1c9a8c499369 100644
--- a/fs/ext4/crypto.c
+++ b/fs/ext4/crypto.c
@@ -314,6 +314,26 @@ static int ext4_page_crypto(struct ext4_crypto_ctx *ctx,
return 0;
}
+static struct page *alloc_bounce_page(struct ext4_crypto_ctx *ctx)
+{
+ struct page *ciphertext_page = alloc_page(GFP_NOFS);
+
+ if (!ciphertext_page) {
+ /* This is a potential bottleneck, but at least we'll have
+ * forward progress. */
+ ciphertext_page = mempool_alloc(ext4_bounce_page_pool,
+ GFP_NOFS);
+ if (ciphertext_page == NULL)
+ return ERR_PTR(-ENOMEM);
+ ctx->flags &= ~EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL;
+ } else {
+ ctx->flags |= EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL;
+ }
+ ctx->flags |= EXT4_WRITE_PATH_FL;
+ ctx->w.bounce_page = ciphertext_page;
+ return ciphertext_page;
+}
+
/**
* ext4_encrypt() - Encrypts a page
* @inode: The inode for which the encryption should take place
@@ -343,28 +363,17 @@ struct page *ext4_encrypt(struct inode *inode,
return (struct page *) ctx;
/* The encryption operation will require a bounce page. */
- ciphertext_page = alloc_page(GFP_NOFS);
- if (!ciphertext_page) {
- /* This is a potential bottleneck, but at least we'll have
- * forward progress. */
- ciphertext_page = mempool_alloc(ext4_bounce_page_pool,
- GFP_NOFS);
- if (WARN_ON_ONCE(!ciphertext_page)) {
- ciphertext_page = mempool_alloc(ext4_bounce_page_pool,
- GFP_NOFS | __GFP_WAIT);
- }
- ctx->flags &= ~EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL;
- } else {
- ctx->flags |= EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL;
- }
- ctx->flags |= EXT4_WRITE_PATH_FL;
- ctx->w.bounce_page = ciphertext_page;
+ ciphertext_page = alloc_bounce_page(ctx);
+ if (IS_ERR(ciphertext_page))
+ goto errout;
ctx->w.control_page = plaintext_page;
err = ext4_page_crypto(ctx, inode, EXT4_ENCRYPT, plaintext_page->index,
plaintext_page, ciphertext_page);
if (err) {
+ ciphertext_page = ERR_PTR(err);
+ errout:
ext4_release_crypto_ctx(ctx);
- return ERR_PTR(err);
+ return ciphertext_page;
}
SetPagePrivate(ciphertext_page);
set_page_private(ciphertext_page, (unsigned long)ctx);
@@ -424,21 +433,11 @@ int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex)
if (IS_ERR(ctx))
return PTR_ERR(ctx);
- ciphertext_page = alloc_page(GFP_NOFS);
- if (!ciphertext_page) {
- /* This is a potential bottleneck, but at least we'll have
- * forward progress. */
- ciphertext_page = mempool_alloc(ext4_bounce_page_pool,
- GFP_NOFS);
- if (WARN_ON_ONCE(!ciphertext_page)) {
- ciphertext_page = mempool_alloc(ext4_bounce_page_pool,
- GFP_NOFS | __GFP_WAIT);
- }
- ctx->flags &= ~EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL;
- } else {
- ctx->flags |= EXT4_BOUNCE_PAGE_REQUIRES_FREE_ENCRYPT_FL;
+ ciphertext_page = alloc_bounce_page(ctx);
+ if (IS_ERR(ciphertext_page)) {
+ err = PTR_ERR(ciphertext_page);
+ goto errout;
}
- ctx->w.bounce_page = ciphertext_page;
while (len--) {
err = ext4_page_crypto(ctx, inode, EXT4_ENCRYPT, lblk,
@@ -460,6 +459,7 @@ int ext4_encrypted_zeroout(struct inode *inode, struct ext4_extent *ex)
goto errout;
}
err = submit_bio_wait(WRITE, bio);
+ bio_put(bio);
if (err)
goto errout;
}