diff options
| author | Dmitry Kasatkin <d.kasatkin@samsung.com> | 2014-02-27 20:16:47 +0200 |
|---|---|---|
| committer | Mimi Zohar <zohar@linux.vnet.ibm.com> | 2014-03-07 12:15:48 -0500 |
| commit | 1d91ac6213003f525ac34da5e39cbb6612d19deb (patch) | |
| tree | 8182a8b6df13e506b1888fce3395b75a9aa1f23b /security/integrity | |
| parent | e0420039b643a832231028000a5c0d7358b14f3b (diff) | |
| download | lwn-1d91ac6213003f525ac34da5e39cbb6612d19deb.tar.gz lwn-1d91ac6213003f525ac34da5e39cbb6612d19deb.zip | |
ima: skip memory allocation for empty files
Memory allocation is unnecessary for empty files.
This patch calculates the hash without memory allocation.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Diffstat (limited to 'security/integrity')
| -rw-r--r-- | security/integrity/ima/ima_crypto.c | 20 |
1 files changed, 12 insertions, 8 deletions
diff --git a/security/integrity/ima/ima_crypto.c b/security/integrity/ima/ima_crypto.c index d257e3631152..1bde8e627766 100644 --- a/security/integrity/ima/ima_crypto.c +++ b/security/integrity/ima/ima_crypto.c @@ -87,16 +87,20 @@ static int ima_calc_file_hash_tfm(struct file *file, if (rc != 0) return rc; - rbuf = kzalloc(PAGE_SIZE, GFP_KERNEL); - if (!rbuf) { - rc = -ENOMEM; + i_size = i_size_read(file_inode(file)); + + if (i_size == 0) goto out; - } + + rbuf = kzalloc(PAGE_SIZE, GFP_KERNEL); + if (!rbuf) + return -ENOMEM; + if (!(file->f_mode & FMODE_READ)) { file->f_mode |= FMODE_READ; read = 1; } - i_size = i_size_read(file_inode(file)); + while (offset < i_size) { int rbuf_len; @@ -113,12 +117,12 @@ static int ima_calc_file_hash_tfm(struct file *file, if (rc) break; } - kfree(rbuf); - if (!rc) - rc = crypto_shash_final(&desc.shash, hash->digest); if (read) file->f_mode &= ~FMODE_READ; + kfree(rbuf); out: + if (!rc) + rc = crypto_shash_final(&desc.shash, hash->digest); return rc; } |