3.18-stable patches

added patches:
	fs-cache-fix-dereference-of-null-user_key_payload.patch

diff --git a/queue-3.18/fs-cache-fix-dereference-of-null-user_key_payload.patch b/queue-3.18/fs-cache-fix-dereference-of-null-user_key_payload.patch
new file mode 100644 (file)
index 0000000..f62452f
--- /dev/null
+++ b/queue-3.18/fs-cache-fix-dereference-of-null-user_key_payload.patch
@@ -0,0 +1,45 @@
+From d124b2c53c7bee6569d2a2d0b18b4a1afde00134 Mon Sep 17 00:00:00 2001
+From: Eric Biggers <ebiggers@google.com>
+Date: Mon, 9 Oct 2017 12:40:00 -0700
+Subject: FS-Cache: fix dereference of NULL user_key_payload
+
+From: Eric Biggers <ebiggers@google.com>
+
+commit d124b2c53c7bee6569d2a2d0b18b4a1afde00134 upstream.
+
+When the file /proc/fs/fscache/objects (available with
+CONFIG_FSCACHE_OBJECT_LIST=y) is opened, we request a user key with
+description "fscache:objlist", then access its payload.  However, a
+revoked key has a NULL payload, and we failed to check for this.
+request_key() *does* skip revoked keys, but there is still a window
+where the key can be revoked before we access its payload.
+
+Fix it by checking for a NULL payload, treating it like a key which was
+already revoked at the time it was requested.
+
+Fixes: 4fbf4291aa15 ("FS-Cache: Allow the current state of all objects to be dumped")
+Reviewed-by: James Morris <james.l.morris@oracle.com>
+Signed-off-by: Eric Biggers <ebiggers@google.com>
+Signed-off-by: David Howells <dhowells@redhat.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+
+---
+ fs/fscache/object-list.c |    7 +++++++
+ 1 file changed, 7 insertions(+)
+
+--- a/fs/fscache/object-list.c
++++ b/fs/fscache/object-list.c
+@@ -330,6 +330,13 @@ static void fscache_objlist_config(struc
+       rcu_read_lock();
+ 
+       confkey = key->payload.data;
++      if (!confkey) {
++              /* key was revoked */
++              rcu_read_unlock();
++              key_put(key);
++              goto no_config;
++      }
++
+       buf = confkey->data;
+ 
+       for (len = confkey->datalen - 1; len >= 0; len--) {

diff --git a/queue-3.18/series b/queue-3.18/series
index 10377a76fbaeb93547baf5ae17d4d2fb9992bdfe..e402baa67c91c507ac960a294b4ead48f2e49ea6 100644 (file)
--- a/queue-3.18/series
+++ b/queue-3.18/series
@@ -18,3 +18,4 @@ cls_api.c-fix-dumping-of-non-existing-actions-stats.patch
 parisc-avoid-trashing-sr2-and-sr3-in-lws-code.patch
 parisc-fix-double-word-compare-and-exchange-in-lws-code-on-32-bit-kernels.patch
 af_packet-don-t-pass-empty-blocks-for-packet_v3.patch
+fs-cache-fix-dereference-of-null-user_key_payload.patch