6.13-stable review patch. If anyone has any objections, please let me know.
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From: Mimi Zohar zohar@linux.ibm.com
commit 5b3cd801155f0b34b0b95942a5b057c9b8cad33e upstream.
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 Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- security/integrity/ima/ima.h | 1 + security/integrity/ima/ima_main.c | 11 +++++++++-- 2 files changed, 10 insertions(+), 2 deletions(-)
--- 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 { --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -137,8 +137,13 @@ static void ima_rdwr_violation_check(str } 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 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) ||