summary refs log tree commit diff
path: root/security
diff options
context:
space:
mode:
authorEric Biggers <ebiggers@google.com>2019-02-14 16:20:01 +0000
committerJames Morris <james.morris@microsoft.com>2019-02-15 14:12:08 -0800
commita08bf91ce28ed3ae7b6fef35d843fef8dc8c2cd9 (patch)
tree55aeebf54986fb1923cbee1d7f202e853b8f609b /security
parent5ded5871030eb75017639148da0a58931dfbfc25 (diff)
downloadlinux-a08bf91ce28ed3ae7b6fef35d843fef8dc8c2cd9.tar.gz
KEYS: allow reaching the keys quotas exactly
If the sysctl 'kernel.keys.maxkeys' is set to some number n, then
actually users can only add up to 'n - 1' keys.  Likewise for
'kernel.keys.maxbytes' and the root_* versions of these sysctls.  But
these sysctls are apparently supposed to be *maximums*, as per their
names and all documentation I could find -- the keyrings(7) man page,
Documentation/security/keys/core.rst, and all the mentions of EDQUOT
meaning that the key quota was *exceeded* (as opposed to reached).

Thus, fix the code to allow reaching the quotas exactly.

Fixes: 0b77f5bfb45c ("keys: make the keyring quotas controllable through /proc/sys")
Cc: stable@vger.kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: James Morris <james.morris@microsoft.com>
Diffstat (limited to 'security')
-rw-r--r--security/keys/key.c4
1 files changed, 2 insertions, 2 deletions
diff --git a/security/keys/key.c b/security/keys/key.c
index 44a80d6741a1..0ec9322af4f9 100644
--- a/security/keys/key.c
+++ b/security/keys/key.c
@@ -265,8 +265,8 @@ struct key *key_alloc(struct key_type *type, const char *desc,
 
 		spin_lock(&user->lock);
 		if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) {
-			if (user->qnkeys + 1 >= maxkeys ||
-			    user->qnbytes + quotalen >= maxbytes ||
+			if (user->qnkeys + 1 > maxkeys ||
+			    user->qnbytes + quotalen > maxbytes ||
 			    user->qnbytes + quotalen < user->qnbytes)
 				goto no_quota;
 		}