keys: allow the callout data to be passed as a blob rather than a string

Allow the callout data to be passed as a blob rather than a string for
internal kernel services that call any request_key_*() interface other than
request_key().  request_key() itself still takes a NUL-terminated string.

The functions that change are:

	request_key_with_auxdata()
	request_key_async()
	request_key_async_with_auxdata()

Signed-off-by: David Howells <dhowells@redhat.com>
Cc: Paul Moore <paul.moore@hp.com>
Cc: Chris Wright <chrisw@sous-sol.org>
Cc: Stephen Smalley <sds@tycho.nsa.gov>
Cc: James Morris <jmorris@namei.org>
Cc: Kevin Coffman <kwc@citi.umich.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 7 insertions, 5 deletions

diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c
index e42b5252486f..c615d473ce7c 100644
--- a/security/keys/request_key_auth.c
+++ b/security/keys/request_key_auth.c
@@ -61,7 +61,7 @@ static void request_key_auth_describe(const struct key *key,
 
         seq_puts(m, "key:");
         seq_puts(m, key->description);
-        seq_printf(m, " pid:%d ci:%zu", rka->pid, strlen(rka->callout_info));
+        seq_printf(m, " pid:%d ci:%zu", rka->pid, rka->callout_len);
 
 } /* end request_key_auth_describe() */
 
@@ -77,7 +77,7 @@ static long request_key_auth_read(const struct key *key,
         size_t datalen;
         long ret;
 
-        datalen = strlen(rka->callout_info);
+        datalen = rka->callout_len;
         ret = datalen;
 
         /* we can return the data as is */
@@ -137,7 +137,8 @@ static void request_key_auth_destroy(struct key *key)
  * create an authorisation token for /sbin/request-key or whoever to gain
  * access to the caller's security data
  */
-struct key *request_key_auth_new(struct key *target, const char *callout_info)
+struct key *request_key_auth_new(struct key *target, const void *callout_info,
+                                 size_t callout_len)
 {
         struct request_key_auth *rka, *irka;
         struct key *authkey = NULL;
@@ -152,7 +153,7 @@ struct key *request_key_auth_new(struct key *target, const char *callout_info)
                 kleave(" = -ENOMEM");
                 return ERR_PTR(-ENOMEM);
         }
-        rka->callout_info = kmalloc(strlen(callout_info) + 1, GFP_KERNEL);
+        rka->callout_info = kmalloc(callout_len, GFP_KERNEL);
         if (!rka->callout_info) {
                 kleave(" = -ENOMEM");
                 kfree(rka);
@@ -186,7 +187,8 @@ struct key *request_key_auth_new(struct key *target, const char *callout_info)
         }
 
         rka->target_key = key_get(target);
-        strcpy(rka->callout_info, callout_info);
+        memcpy(rka->callout_info, callout_info, callout_len);
+        rka->callout_len = callout_len;
 
         /* allocate the auth key */
         sprintf(desc, "%x", target->serial);