From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Petr Matousek <pmatouse@redhat.com>,
David Howells <dhowells@redhat.com>
Subject: [PATCH 3.10 32/35] KEYS: Fix race between key destruction and finding a keyring by name
Date: Wed, 20 Jan 2016 14:01:02 -0800 [thread overview]
Message-ID: <20160120211955.240868791@linuxfoundation.org> (raw)
In-Reply-To: <20160120211951.234493363@linuxfoundation.org>
3.10-stable review patch. If anyone has any objections, please let me know.
------------------
From: David Howells <dhowells@redhat.com>
commit 94c4554ba07adbdde396748ee7ae01e86cf2d8d7 upstream.
There appears to be a race between:
(1) key_gc_unused_keys() which frees key->security and then calls
keyring_destroy() to unlink the name from the name list
(2) find_keyring_by_name() which calls key_permission(), thus accessing
key->security, on a key before checking to see whether the key usage is 0
(ie. the key is dead and might be cleaned up).
Fix this by calling ->destroy() before cleaning up the core key data -
including key->security.
Reported-by: Petr Matousek <pmatouse@redhat.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
security/keys/gc.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
--- a/security/keys/gc.c
+++ b/security/keys/gc.c
@@ -187,6 +187,10 @@ static noinline void key_gc_unused_keys(
kdebug("- %u", key->serial);
key_check(key);
+ /* Throw away the key data */
+ if (key->type->destroy)
+ key->type->destroy(key);
+
security_key_free(key);
/* deal with the user's key tracking and quota */
@@ -201,10 +205,6 @@ static noinline void key_gc_unused_keys(
if (test_bit(KEY_FLAG_INSTANTIATED, &key->flags))
atomic_dec(&key->user->nikeys);
- /* now throw away the key memory */
- if (key->type->destroy)
- key->type->destroy(key);
-
key_user_put(key->user);
kfree(key->description);
next prev parent reply other threads:[~2016-01-20 22:01 UTC|newest]
Thread overview: 39+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-01-20 22:00 [PATCH 3.10 00/35] 3.10.95-stable review Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 01/35] unix: avoid use-after-free in ep_remove_wait_queue Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 02/35] sctp: translate host order to network order when setting a hmacid Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 03/35] snmp: Remove duplicate OUTMCAST stat increment Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 05/35] tcp: md5: fix lockdep annotation Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 06/35] tcp: initialize tp->copied_seq in case of cross SYN connection Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 07/35] net, scm: fix PaX detected msg_controllen overflow in scm_detach_fds Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 08/35] net: ipmr: fix static mfc/dev leaks on table destruction Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 09/35] net: ip6mr: " Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 10/35] broadcom: fix PHY_ID_BCM5481 entry in the id table Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 11/35] ipv6: distinguish frag queues by device for multicast and link-local packets Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 12/35] ipv6: sctp: implement sctp_v6_destroy_sock() Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 13/35] Btrfs: fix race leading to BUG_ON when running delalloc for nodatacow Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 14/35] ext4, jbd2: ensure entering into panic after recording an error in superblock Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 15/35] firewire: ohci: fix JMicron JMB38x IT context discovery Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 16/35] nfs4: start callback_ident at idr 1 Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 17/35] nfs: if we have no valid attrs, then dont declare the attribute cache valid Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 18/35] USB: cdc_acm: Ignore Infineon Flash Loader utility Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 19/35] USB: cp210x: Remove CP2110 ID from compatibility list Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 20/35] USB: add quirk for devices with broken LPM Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 21/35] USB: whci-hcd: add check for dma mapping error Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 22/35] usb: Use the USB_SS_MULT() macro to decode burst multiplier for log message Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 23/35] gre6: allow to update all parameters via rtnl Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 24/35] atl1c: Improve driver not to do order 4 GFP_ATOMIC allocation Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 25/35] sctp: update the netstamp_needed counter when copying sockets Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 26/35] ipv6: sctp: clone options to avoid use after free Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 28/35] sh_eth: fix kernel oops in skb_put() Greg Kroah-Hartman
2016-01-20 22:00 ` [PATCH 3.10 29/35] pptp: verify sockaddr_len in pptp_bind() and pptp_connect() Greg Kroah-Hartman
2016-01-20 22:01 ` [PATCH 3.10 30/35] bluetooth: Validate socket address length in sco_sock_bind() Greg Kroah-Hartman
2016-01-20 22:01 ` [PATCH 3.10 31/35] af_unix: Revert lock_interruptible in stream receive code Greg Kroah-Hartman
2016-01-20 22:01 ` Greg Kroah-Hartman [this message]
2016-01-20 22:01 ` [PATCH 3.10 33/35] KEYS: Fix crash when attempt to garbage collect an uninstantiated keyring Greg Kroah-Hartman
2016-01-20 22:01 ` [PATCH 3.10 34/35] KEYS: Fix race between read and revoke Greg Kroah-Hartman
2016-01-20 22:01 ` [PATCH 3.10 35/35] KEYS: Fix keyring ref leak in join_session_keyring() Greg Kroah-Hartman
2016-01-20 23:14 ` [PATCH 3.10 00/35] 3.10.95-stable review Shuah Khan
2016-01-21 7:06 ` Willy Tarreau
2016-01-22 7:52 ` Greg Kroah-Hartman
2016-01-22 8:30 ` Willy Tarreau
2016-01-21 12:20 ` Guenter Roeck
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