From 17f4bad3abc7c09f42987d89ccccab02c03455a9 Mon Sep 17 00:00:00 2001 From: Dmitry Kasatkin Date: Tue, 19 Aug 2014 16:48:39 +0300 Subject: [PATCH] ima: remove usage of filename parameter In all cases except ima_bprm_check() the filename was not defined and ima_d_path() was used to find the full path. Unfortunately, the bprm filename is a relative pathname (eg. .//filename). ima_bprm_check() selects between bprm->interp and bprm->filename. The following dump demonstrates the differences between using filename and interp. bprm->filename filename: ./foo.sh, pathname: /root/bin/foo.sh filename: ./foo.sh, pathname: /bin/dash bprm->interp filename: ./foo.sh, pathname: /root/bin/foo.sh filename: /bin/sh, pathname: /bin/dash In both cases the pathnames are currently the same. This patch removes usage of filename and interp in favor of d_absolute_path. Changes v3: - 11 extra bytes for "deleted" not needed (Mimi) - purpose "replace relative bprm filename with full pathname" (Mimi) Changes v2: - use d_absolute_path() instead of d_path to work in chroot environments. Signed-off-by: Dmitry Kasatkin Signed-off-by: Mimi Zohar --- security/integrity/ima/ima_api.c | 5 ++--- security/integrity/ima/ima_main.c | 19 ++++++++----------- 2 files changed, 10 insertions(+), 14 deletions(-) diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c index d9cd5ce14d2b..65c41a968cc1 100644 --- a/security/integrity/ima/ima_api.c +++ b/security/integrity/ima/ima_api.c @@ -330,10 +330,9 @@ const char *ima_d_path(struct path *path, char **pathbuf) { char *pathname = NULL; - /* We will allow 11 spaces for ' (deleted)' to be appended */ - *pathbuf = kmalloc(PATH_MAX + 11, GFP_KERNEL); + *pathbuf = kmalloc(PATH_MAX, GFP_KERNEL); if (*pathbuf) { - pathname = d_path(path, *pathbuf, PATH_MAX + 11); + pathname = d_absolute_path(path, *pathbuf, PATH_MAX); if (IS_ERR(pathname)) { kfree(*pathbuf); *pathbuf = NULL; diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c index aaf5552e808d..673a37e92ba3 100644 --- a/security/integrity/ima/ima_main.c +++ b/security/integrity/ima/ima_main.c @@ -156,8 +156,8 @@ void ima_file_free(struct file *file) ima_check_last_writer(iint, inode, file); } -static int process_measurement(struct file *file, const char *filename, - int mask, int function, int opened) +static int process_measurement(struct file *file, int mask, int function, + int opened) { struct inode *inode = file_inode(file); struct integrity_iint_cache *iint; @@ -218,7 +218,7 @@ static int process_measurement(struct file *file, const char *filename, goto out_digsig; } - pathname = filename ?: ima_d_path(&file->f_path, &pathbuf); + pathname = ima_d_path(&file->f_path, &pathbuf); if (action & IMA_MEASURE) ima_store_measurement(iint, file, pathname, @@ -254,7 +254,7 @@ out: int ima_file_mmap(struct file *file, unsigned long prot) { if (file && (prot & PROT_EXEC)) - return process_measurement(file, NULL, MAY_EXEC, MMAP_CHECK, 0); + return process_measurement(file, MAY_EXEC, MMAP_CHECK, 0); return 0; } @@ -273,10 +273,7 @@ int ima_file_mmap(struct file *file, unsigned long prot) */ int ima_bprm_check(struct linux_binprm *bprm) { - return process_measurement(bprm->file, - (strcmp(bprm->filename, bprm->interp) == 0) ? - bprm->filename : bprm->interp, - MAY_EXEC, BPRM_CHECK, 0); + return process_measurement(bprm->file, MAY_EXEC, BPRM_CHECK, 0); } /** @@ -292,7 +289,7 @@ int ima_bprm_check(struct linux_binprm *bprm) int ima_file_check(struct file *file, int mask, int opened) { ima_rdwr_violation_check(file); - return process_measurement(file, NULL, + return process_measurement(file, mask & (MAY_READ | MAY_WRITE | MAY_EXEC), FILE_CHECK, opened); } @@ -317,7 +314,7 @@ int ima_module_check(struct file *file) #endif return 0; /* We rely on module signature checking */ } - return process_measurement(file, NULL, MAY_EXEC, MODULE_CHECK, 0); + return process_measurement(file, MAY_EXEC, MODULE_CHECK, 0); } int ima_fw_from_file(struct file *file, char *buf, size_t size) @@ -328,7 +325,7 @@ int ima_fw_from_file(struct file *file, char *buf, size_t size) return -EACCES; /* INTEGRITY_UNKNOWN */ return 0; } - return process_measurement(file, NULL, MAY_EXEC, FIRMWARE_CHECK, 0); + return process_measurement(file, MAY_EXEC, FIRMWARE_CHECK, 0); } static int __init init_ima(void) -- 2.39.5