lkml.org 
[lkml]   [2017]   [Oct]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 14/15] KEYS: load key flags and expiry time atomically in keyring_search_iterator()
Date
From: Eric Biggers <ebiggers@google.com>

Similar to the case for key_validate(), we should load the key ->flags
and ->expiry once atomically in keyring_search_iterator(), since they
can be changed concurrently whenever the key semaphore isn't held.

Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: David Howells <dhowells@redhat.com>
---

security/keys/keyring.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/security/keys/keyring.c b/security/keys/keyring.c
index 816948abff89..1ef5c7caf15c 100644
--- a/security/keys/keyring.c
+++ b/security/keys/keyring.c
@@ -566,6 +566,8 @@ static int keyring_search_iterator(const void *object, void *iterator_data)

/* skip invalidated, revoked and expired keys */
if (ctx->flags & KEYRING_SEARCH_DO_STATE_CHECK) {
+ time_t expiry = READ_ONCE(key->expiry);
+
if (kflags & ((1 << KEY_FLAG_INVALIDATED) |
(1 << KEY_FLAG_REVOKED))) {
ctx->result = ERR_PTR(-EKEYREVOKED);
@@ -573,7 +575,7 @@ static int keyring_search_iterator(const void *object, void *iterator_data)
goto skipped;
}

- if (key->expiry && ctx->now.tv_sec >= key->expiry) {
+ if (expiry && ctx->now.tv_sec >= expiry) {
if (!(ctx->flags & KEYRING_SEARCH_SKIP_EXPIRED))
ctx->result = ERR_PTR(-EKEYEXPIRED);
kleave(" = %d [expire]", ctx->skipped_ret);
\
 
 \ /
  Last update: 2017-10-12 22:18    [W:0.107 / U:0.128 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site