diff mbox series

[13/13] security/integrity/ima: converts stats to seqnum_ops

Message ID cbc346bbeb306db3effefac0d27c93e143ac0442.1605027593.git.skhan@linuxfoundation.org (mailing list archive)
State New
Headers show
Series Introduce seqnum_ops | expand

Commit Message

Shuah Khan Nov. 10, 2020, 7:53 p.m. UTC
seqnum_ops api is introduced to be used when a variable is used as
a sequence/stat counter and doesn't guard object lifetimes. This
clearly differentiates atomic_t usages that guard object lifetimes.

seqnum32 variables wrap around to INT_MIN when it overflows and
should not be used to guard resource lifetimes, device usage and
open counts that control state changes, and pm states.

atomic_t variables used for eima_htable.violations and number of stored
measurements and ios_threshold are atomic counters, and violations is
only an idicator and can overflow. No chane to the behavior with this
change.

Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
---
 security/integrity/ima/ima.h       | 5 +++--
 security/integrity/ima/ima_api.c   | 2 +-
 security/integrity/ima/ima_fs.c    | 4 ++--
 security/integrity/ima/ima_queue.c | 7 ++++---
 4 files changed, 10 insertions(+), 8 deletions(-)

Comments

kernel test robot Nov. 11, 2020, 8:51 a.m. UTC | #1
Hi Shuah,

I love your patch! Perhaps something to improve:

[auto build test WARNING on staging/staging-testing]
[also build test WARNING on integrity/next-integrity char-misc/char-misc-testing usb/usb-testing linus/master v5.10-rc3 next-20201110]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Shuah-Khan/Introduce-seqnum_ops/20201111-035753
base:   https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/staging.git f4acd33c446b2ba97f1552a4da90050109d01ca7
config: sh-allmodconfig (attached as .config)
compiler: sh4-linux-gcc (GCC) 9.3.0
reproduce (this is a W=1 build):
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # https://github.com/0day-ci/linux/commit/4124aef613b0e30b7da08aaec750983854e1ca5a
        git remote add linux-review https://github.com/0day-ci/linux
        git fetch --no-tags linux-review Shuah-Khan/Introduce-seqnum_ops/20201111-035753
        git checkout 4124aef613b0e30b7da08aaec750983854e1ca5a
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=sh 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

   In file included from security/integrity/ima/ima_fs.c:25:
   security/integrity/ima/ima.h:178:18: error: field 'len' has incomplete type
     178 |  struct seqnum64 len; /* number of stored measurements in the list */
         |                  ^~~
   security/integrity/ima/ima.h:179:18: error: field 'violations' has incomplete type
     179 |  struct seqnum64 violations;
         |                  ^~~~~~~~~~
   security/integrity/ima/ima_fs.c: In function 'ima_show_htable_value':
   security/integrity/ima/ima_fs.c:47:52: error: implicit declaration of function 'seqnum64_read'; did you mean 'seqnum32_read'? [-Werror=implicit-function-declaration]
      47 |  len = scnprintf(tmpbuf, sizeof(tmpbuf), "%lli\n", seqnum64_read(val));
         |                                                    ^~~~~~~~~~~~~
         |                                                    seqnum32_read
>> security/integrity/ima/ima_fs.c:47:46: warning: format '%lli' expects argument of type 'long long int', but argument 4 has type 'int' [-Wformat=]
      47 |  len = scnprintf(tmpbuf, sizeof(tmpbuf), "%lli\n", seqnum64_read(val));
         |                                           ~~~^     ~~~~~~~~~~~~~~~~~~
         |                                              |     |
         |                                              |     int
         |                                              long long int
         |                                           %i
   security/integrity/ima/ima_fs.c: In function 'ima_show_htable_violations':
   security/integrity/ima/ima_fs.c:56:1: error: control reaches end of non-void function [-Werror=return-type]
      56 | }
         | ^
   security/integrity/ima/ima_fs.c: In function 'ima_show_measurements_count':
   security/integrity/ima/ima_fs.c:69:1: error: control reaches end of non-void function [-Werror=return-type]
      69 | }
         | ^
   cc1: some warnings being treated as errors

vim +47 security/integrity/ima/ima_fs.c

    40	
    41	static ssize_t ima_show_htable_value(char __user *buf, size_t count,
    42					     loff_t *ppos, struct seqnum64 *val)
    43	{
    44		char tmpbuf[32];	/* greater than largest 'long' string value */
    45		ssize_t len;
    46	
  > 47		len = scnprintf(tmpbuf, sizeof(tmpbuf), "%lli\n", seqnum64_read(val));
    48		return simple_read_from_buffer(buf, count, ppos, tmpbuf, len);
    49	}
    50	

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org
diff mbox series

Patch

diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
index 6ebefec616e4..55fe1d14c67a 100644
--- a/security/integrity/ima/ima.h
+++ b/security/integrity/ima/ima.h
@@ -21,6 +21,7 @@ 
 #include <linux/tpm.h>
 #include <linux/audit.h>
 #include <crypto/hash_info.h>
+#include <linux/seqnum_ops.h>
 
 #include "../integrity.h"
 
@@ -174,8 +175,8 @@  int ima_lsm_policy_change(struct notifier_block *nb, unsigned long event,
 extern spinlock_t ima_queue_lock;
 
 struct ima_h_table {
-	atomic_long_t len;	/* number of stored measurements in the list */
-	atomic_long_t violations;
+	struct seqnum64 len;	/* number of stored measurements in the list */
+	struct seqnum64 violations;
 	struct hlist_head queue[IMA_MEASURE_HTABLE_SIZE];
 };
 extern struct ima_h_table ima_htable;
diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c
index 4f39fb93f278..b1a203435698 100644
--- a/security/integrity/ima/ima_api.c
+++ b/security/integrity/ima/ima_api.c
@@ -144,7 +144,7 @@  void ima_add_violation(struct file *file, const unsigned char *filename,
 	int result;
 
 	/* can overflow, only indicator */
-	atomic_long_inc(&ima_htable.violations);
+	seqnum64_inc(&ima_htable.violations);
 
 	result = ima_alloc_init_template(&event_data, &entry, NULL);
 	if (result < 0) {
diff --git a/security/integrity/ima/ima_fs.c b/security/integrity/ima/ima_fs.c
index ea8ff8a07b36..03a78b445052 100644
--- a/security/integrity/ima/ima_fs.c
+++ b/security/integrity/ima/ima_fs.c
@@ -39,12 +39,12 @@  __setup("ima_canonical_fmt", default_canonical_fmt_setup);
 static int valid_policy = 1;
 
 static ssize_t ima_show_htable_value(char __user *buf, size_t count,
-				     loff_t *ppos, atomic_long_t *val)
+				     loff_t *ppos, struct seqnum64 *val)
 {
 	char tmpbuf[32];	/* greater than largest 'long' string value */
 	ssize_t len;
 
-	len = scnprintf(tmpbuf, sizeof(tmpbuf), "%li\n", atomic_long_read(val));
+	len = scnprintf(tmpbuf, sizeof(tmpbuf), "%lli\n", seqnum64_read(val));
 	return simple_read_from_buffer(buf, count, ppos, tmpbuf, len);
 }
 
diff --git a/security/integrity/ima/ima_queue.c b/security/integrity/ima/ima_queue.c
index c096ef8945c7..87db50dd1721 100644
--- a/security/integrity/ima/ima_queue.c
+++ b/security/integrity/ima/ima_queue.c
@@ -17,6 +17,7 @@ 
 
 #include <linux/rculist.h>
 #include <linux/slab.h>
+#include <linux/seqnum_ops.h>
 #include "ima.h"
 
 #define AUDIT_CAUSE_LEN_MAX 32
@@ -33,8 +34,8 @@  static unsigned long binary_runtime_size = ULONG_MAX;
 
 /* key: inode (before secure-hashing a file) */
 struct ima_h_table ima_htable = {
-	.len = ATOMIC_LONG_INIT(0),
-	.violations = ATOMIC_LONG_INIT(0),
+	.len = SEQNUM_INIT(0),
+	.violations = SEQNUM_INIT(0),
 	.queue[0 ... IMA_MEASURE_HTABLE_SIZE - 1] = HLIST_HEAD_INIT
 };
 
@@ -106,7 +107,7 @@  static int ima_add_digest_entry(struct ima_template_entry *entry,
 	INIT_LIST_HEAD(&qe->later);
 	list_add_tail_rcu(&qe->later, &ima_measurements);
 
-	atomic_long_inc(&ima_htable.len);
+	seqnum64_inc(&ima_htable.len);
 	if (update_htable) {
 		key = ima_hash_key(entry->digests[ima_hash_algo_idx].digest);
 		hlist_add_head_rcu(&qe->hnext, &ima_htable.queue[key]);