From 08e1b76ae399a010c0d0916b125d75aed6961d16 Mon Sep 17 00:00:00 2001 From: Mimi Zohar Date: Wed, 20 Jun 2012 09:32:55 -0400 Subject: [PATCH] ima: use full pathnames in measurement list The IMA measurement list contains filename hints, which can be ambigious without the full pathname. This patch replaces the filename hint with the full pathname, simplifying for userspace the correlating of file hash measurements with files. Change log v1: - Revert to short filenames, when full pathname is longer than IMA measurement buffer size. (Based on Dmitry's review) Signed-off-by: Mimi Zohar --- security/integrity/ima/ima_api.c | 4 ++- security/integrity/ima/ima_main.c | 42 ++++++++++++++++++++++++++----- 2 files changed, 39 insertions(+), 7 deletions(-) diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index 88a2788b981d..032ff03ad907 100644 --- a/security/integrity/ima/ima_api.c +++ b/security/integrity/ima/ima_api.c @@ -175,7 +175,9 @@ void ima_store_measurement(struct integrity_iint_cache *iint, } memset(&entry->template, 0, sizeof(entry->template)); memcpy(entry->template.digest, iint->digest, IMA_DIGEST_SIZE); - strncpy(entry->template.file_name, filename, IMA_EVENT_NAME_LEN_MAX); + strcpy(entry->template.file_name, + (strlen(filename) > IMA_EVENT_NAME_LEN_MAX) ? + file->f_dentry->d_name.name : filename); result = ima_store_template(entry, violation, inode); if (!result || result == -EEXIST) diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index b17be79b9cf2..a0e631a19058 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -54,6 +54,7 @@ static void ima_rdwr_violation_check(struct file *file) fmode_t mode = file->f_mode; int rc; bool send_tomtou = false, send_writers = false; + unsigned char *pathname = NULL, *pathbuf = NULL; if (!S_ISREG(inode->i_mode) || !ima_initialized) return; @@ -75,12 +76,27 @@ static void ima_rdwr_violation_check(struct file *file) out: mutex_unlock(&inode->i_mutex); + if (!send_tomtou && !send_writers) + return; + + /* We will allow 11 spaces for ' (deleted)' to be appended */ + pathbuf = kmalloc(PATH_MAX + 11, GFP_KERNEL); + if (pathbuf) { + pathname = d_path(&file->f_path, pathbuf, PATH_MAX + 11); + if (IS_ERR(pathname)) + pathname = NULL; + else if (strlen(pathname) > IMA_EVENT_NAME_LEN_MAX) + pathname = NULL; + } if (send_tomtou) - ima_add_violation(inode, dentry->d_name.name, "invalid_pcr", - "ToMToU"); + ima_add_violation(inode, + !pathname ? dentry->d_name.name : pathname, + "invalid_pcr", "ToMToU"); if (send_writers) - ima_add_violation(inode, dentry->d_name.name, "invalid_pcr", - "open_writers"); + ima_add_violation(inode, + !pathname ? dentry->d_name.name : pathname, + "invalid_pcr", "open_writers"); + kfree(pathbuf); } static void ima_check_last_writer(struct integrity_iint_cache *iint, @@ -123,6 +139,7 @@ static int process_measurement(struct file *file, const unsigned char *filename, { struct inode *inode = file->f_dentry->d_inode; struct integrity_iint_cache *iint; + unsigned char *pathname = NULL, *pathbuf = NULL; int rc = 0; if (!ima_initialized || !S_ISREG(inode->i_mode)) @@ -147,8 +164,21 @@ retry: goto out; rc = ima_collect_measurement(iint, file); - if (!rc) - ima_store_measurement(iint, file, filename); + if (rc != 0) + goto out; + + if (function != BPRM_CHECK) { + /* We will allow 11 spaces for ' (deleted)' to be appended */ + pathbuf = kmalloc(PATH_MAX + 11, GFP_KERNEL); + if (pathbuf) { + pathname = + d_path(&file->f_path, pathbuf, PATH_MAX + 11); + if (IS_ERR(pathname)) + pathname = NULL; + } + } + ima_store_measurement(iint, file, !pathname ? filename : pathname); + kfree(pathbuf); out: mutex_unlock(&iint->mutex); return rc; -- 2.30.2