diff options
| author | Mimi Zohar <zohar@linux.ibm.com> | 2025-01-27 10:24:13 -0500 |
|---|---|---|
| committer | Mimi Zohar <zohar@linux.ibm.com> | 2025-03-27 12:35:51 -0400 |
| commit | 5b3cd801155f0b34b0b95942a5b057c9b8cad33e (patch) | |
| tree | a53bd26b496d35aef749282bb519e213c2b077d4 /security | |
| parent | 7eb172143d5508b4da468ed59ee857c6e5e01da6 (diff) | |
ima: limit the number of open-writers integrity violations
Each time a file in policy, that is already opened for write, is opened
for read, an open-writers integrity violation audit message is emitted
and a violation record is added to the IMA measurement list. This
occurs even if an open-writers violation has already been recorded.
Limit the number of open-writers integrity violations for an existing
file open for write to one. After the existing file open for write
closes (__fput), subsequent open-writers integrity violations may be
emitted.
Cc: stable@vger.kernel.org # applies cleanly up to linux-6.6
Tested-by: Stefan Berger <stefanb@linux.ibm.com>
Reviewed-by: Petr Vorel <pvorel@suse.cz>
Tested-by: Petr Vorel <pvorel@suse.cz>
Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Diffstat (limited to 'security')
| -rw-r--r-- | security/integrity/ima/ima.h | 1 | ||||
| -rw-r--r-- | security/integrity/ima/ima_main.c | 11 |
2 files changed, 10 insertions, 2 deletions
diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h index a4f284bd846c..3423b3088de5 100644 --- a/security/integrity/ima/ima.h +++ b/security/integrity/ima/ima.h @@ -182,6 +182,7 @@ struct ima_kexec_hdr { #define IMA_CHANGE_ATTR 2 #define IMA_DIGSIG 3 #define IMA_MUST_MEASURE 4 +#define IMA_EMITTED_OPENWRITERS 5 /* IMA integrity metadata associated with an inode */ struct ima_iint_cache { diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index 28b8b0db6f9b..95118c1887cb 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -137,8 +137,13 @@ static void ima_rdwr_violation_check(struct file *file, } else { if (must_measure) set_bit(IMA_MUST_MEASURE, &iint->atomic_flags); - if (inode_is_open_for_write(inode) && must_measure) - send_writers = true; + + /* Limit number of open_writers violations */ + if (inode_is_open_for_write(inode) && must_measure) { + if (!test_and_set_bit(IMA_EMITTED_OPENWRITERS, + &iint->atomic_flags)) + send_writers = true; + } } if (!send_tomtou && !send_writers) @@ -167,6 +172,8 @@ static void ima_check_last_writer(struct ima_iint_cache *iint, if (atomic_read(&inode->i_writecount) == 1) { struct kstat stat; + clear_bit(IMA_EMITTED_OPENWRITERS, &iint->atomic_flags); + update = test_and_clear_bit(IMA_UPDATE_XATTR, &iint->atomic_flags); if ((iint->flags & IMA_NEW_FILE) || |