rpms/kernel
3
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

CVE-2015-7099 RDS: race condition on unbound socket null deref (rhbz 1276437 1276438)

Browse Source
This commit is contained in:
Josh Boyer 2015-10-29 13:45:31 -04:00
parent 22faa3a329
commit fec1f7de1f
2 changed files with 83 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

77
RDS-fix-race-condition-when-sending-a-message-on-unb.patch Normal file
View File

@ -0,0 +1,77 @@
From 8e92c2b0cb50a31e2956760498bc8cdb72993fb3 Mon Sep 17 00:00:00 2001
From: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Date: Fri, 16 Oct 2015 17:11:42 +0200
Subject: [PATCH] RDS: fix race condition when sending a message on unbound
socket.
Sasha's found a NULL pointer dereference in the RDS connection code when
sending a message to an apparently unbound socket. The problem is caused
by the code checking if the socket is bound in rds_sendmsg(), which checks
the rs_bound_addr field without taking a lock on the socket. This opens a
race where rs_bound_addr is temporarily set but where the transport is not
in rds_bind(), leading to a NULL pointer dereference when trying to
dereference 'trans' in __rds_conn_create().
Vegard wrote a reproducer for this issue, so kindly ask him to share if
you're interested.
I cannot reproduce the NULL pointer dereference using Vegard's reproducer
with this patch, whereas I could without.
Complete earlier incomplete fix to CVE-2015-6937:
74e98eb08588 ("RDS: verify the underlying transport exists before creating a connection")
Signed-off-by: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Reviewed-by: Vegard Nossum <vegard.nossum@oracle.com>
Reviewed-by: Sasha Levin <sasha.levin@oracle.com>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Sasha Levin <sasha.levin@oracle.com>
Cc: Chien Yen <chien.yen@oracle.com>
Cc: Santosh Shilimkar <santosh.shilimkar@oracle.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: stable@vger.kernel.org
---
net/rds/connection.c | 6 ------
net/rds/send.c | 4 +++-
2 files changed, 3 insertions(+), 7 deletions(-)
diff --git a/net/rds/connection.c b/net/rds/connection.c
index 49adeef8090c..9b2de5e67d79 100644
--- a/net/rds/connection.c
+++ b/net/rds/connection.c
@@ -190,12 +190,6 @@ new_conn:
}
}
- if (trans == NULL) {
- kmem_cache_free(rds_conn_slab, conn);
- conn = ERR_PTR(-ENODEV);
- goto out;
- }
-
conn->c_trans = trans;
ret = trans->conn_alloc(conn, gfp);
diff --git a/net/rds/send.c b/net/rds/send.c
index 4df61a515b83..859de6f32521 100644
--- a/net/rds/send.c
+++ b/net/rds/send.c
@@ -1009,11 +1009,13 @@ int rds_sendmsg(struct socket *sock, struct msghdr *msg, size_t payload_len)
release_sock(sk);
}
- /* racing with another thread binding seems ok here */
+ lock_sock(sk);
if (daddr == 0 || rs->rs_bound_addr == 0) {
+ release_sock(sk);
ret = -ENOTCONN; /* XXX not a great errno */
goto out;
}
+ release_sock(sk);
if (payload_len > rds_sk_sndbuf(rs)) {
ret = -EMSGSIZE;
--
2.4.3

6
kernel.spec
View File

@ -590,6 +590,9 @@ Patch509: ideapad-laptop-Add-Lenovo-Yoga-3-14-to-no_hw_rfkill-.patch
#rhbz 1275490
Patch510: 0001-iwlwifi-Add-new-PCI-IDs-for-the-8260-series.patch
#CVE-2015-7990 rhbz 1276437 1276438
Patch511: RDS-fix-race-condition-when-sending-a-message-on-unb.patch
Patch904: kdbus.patch
# END OF PATCH DEFINITIONS
@ -2035,6 +2038,9 @@ fi
#
#
%changelog
* Thu Oct 29 2015 Josh Boyer <jwboyer@fedoraproject.org>
- CVE-2015-7099 RDS: race condition on unbound socket null deref (rhbz 1276437 1276438)
* Thu Oct 29 2015 Josh Boyer <jwboyer@fedoraproject.org>
- Move iscsi_tcp and related modules to kernel-core (rhbz 1249424)