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. ./<dir>/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 <d.kasatkin@samsung.com>
Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com>
This commit is contained in:
Dmitry Kasatkin 2014-08-19 16:48:39 +03:00 committed by Mimi Zohar
parent 86f2bc0249
commit 17f4bad3ab
2 changed files with 10 additions and 14 deletions

View file

@ -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;

View file

@ -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 @@ static int process_measurement(struct file *file, const char *filename,
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)