diff options
author | Dmitry Kasatkin <d.kasatkin@samsung.com> | 2014-06-27 18:04:27 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2014-10-30 09:38:24 -0700 |
commit | 4e9c74a3333fbb7ce5fd575ae2649bf4e1130775 (patch) | |
tree | 485481fc7b7990132f3cf21e821522df5f90efd2 /security | |
parent | 5d8f79d49db525d29cf7d9251b35ff7fbeec7b1c (diff) | |
download | lwn-4e9c74a3333fbb7ce5fd575ae2649bf4e1130775.tar.gz lwn-4e9c74a3333fbb7ce5fd575ae2649bf4e1130775.zip |
ima: provide flag to identify new empty files
commit b151d6b00bbb798c58f2f21305e7d43fa763f34f upstream.
On ima_file_free(), newly created empty files are not labeled with
an initial security.ima value, because the iversion did not change.
Commit dff6efc "fs: fix iversion handling" introduced a change in
iversion behavior. To verify this change use the shell command:
$ (exec >foo)
$ getfattr -h -e hex -d -m security foo
This patch defines the IMA_NEW_FILE flag. The flag is initially
set, when IMA detects that a new file is created, and subsequently
checked on the ima_file_free() hook to set the initial security.ima
value.
Signed-off-by: Dmitry Kasatkin <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'security')
-rw-r--r-- | security/integrity/ima/ima_appraise.c | 7 | ||||
-rw-r--r-- | security/integrity/ima/ima_main.c | 12 | ||||
-rw-r--r-- | security/integrity/integrity.h | 1 |
3 files changed, 13 insertions, 7 deletions
diff --git a/security/integrity/ima/ima_appraise.c b/security/integrity/ima/ima_appraise.c index 734e9468aca0..6df1b2527d02 100644 --- a/security/integrity/ima/ima_appraise.c +++ b/security/integrity/ima/ima_appraise.c @@ -194,8 +194,11 @@ int ima_appraise_measurement(int func, struct integrity_iint_cache *iint, goto out; cause = "missing-hash"; - status = - (inode->i_size == 0) ? INTEGRITY_PASS : INTEGRITY_NOLABEL; + status = INTEGRITY_NOLABEL; + if (inode->i_size == 0) { + iint->flags |= IMA_NEW_FILE; + status = INTEGRITY_PASS; + } goto out; } diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 76d8aad146a8..9f70efd08058 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -131,11 +131,13 @@ static void ima_check_last_writer(struct integrity_iint_cache *iint, return; mutex_lock(&inode->i_mutex); - if (atomic_read(&inode->i_writecount) == 1 && - iint->version != inode->i_version) { - iint->flags &= ~IMA_DONE_MASK; - if (iint->flags & IMA_APPRAISE) - ima_update_xattr(iint, file); + if (atomic_read(&inode->i_writecount) == 1) { + if ((iint->version != inode->i_version) || + (iint->flags & IMA_NEW_FILE)) { + iint->flags &= ~(IMA_DONE_MASK | IMA_NEW_FILE); + if (iint->flags & IMA_APPRAISE) + ima_update_xattr(iint, file); + } } mutex_unlock(&inode->i_mutex); } diff --git a/security/integrity/integrity.h b/security/integrity/integrity.h index 33c0a70f6b15..2f8715d77a5a 100644 --- a/security/integrity/integrity.h +++ b/security/integrity/integrity.h @@ -31,6 +31,7 @@ #define IMA_DIGSIG 0x01000000 #define IMA_DIGSIG_REQUIRED 0x02000000 #define IMA_PERMIT_DIRECTIO 0x04000000 +#define IMA_NEW_FILE 0x08000000 #define IMA_DO_MASK (IMA_MEASURE | IMA_APPRAISE | IMA_AUDIT | \ IMA_APPRAISE_SUBMASK) |