netdev - [PATCH net 1/2] vxlan: use the correct nlattr array in NL_SET_ERR_MSG

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Wed, 22 Apr 2020 17:29:50 +0200
From:   Sabrina Dubroca <sd@...asysnail.net>
To:     netdev@...r.kernel.org
Cc:     Xin Long <lucien.xin@...il.com>,
        Stefano Brivio <sbrivio@...hat.com>,
        Girish Moodalbail <girish.moodalbail@...cle.com>,
        Matthias Schiffer <mschiffer@...verse-factory.net>,
        Sabrina Dubroca <sd@...asysnail.net>
Subject: [PATCH net 1/2] vxlan: use the correct nlattr array in NL_SET_ERR_MSG_ATTR

IFLA_VXLAN_* attributes are in the data array, which is correctly
used when fetching the value, but not when setting the extended
ack. Because IFLA_VXLAN_MAX < IFLA_MAX, we avoid out of bounds
array accesses, but we don't provide a pointer to the invalid
attribute to userspace.

Fixes: 653ef6a3e4af ("vxlan: change vxlan_[config_]validate() to use netlink_ext_ack for error reporting")
Fixes: b4d3069783bc ("vxlan: Allow configuration of DF behaviour")
Signed-off-by: Sabrina Dubroca <sd@...asysnail.net>
---
 drivers/net/vxlan.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index 45308b3350cf..a5b415fed11e 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -3144,7 +3144,7 @@ static int vxlan_validate(struct nlattr *tb[], struct nlattr *data[],
 		u32 id = nla_get_u32(data[IFLA_VXLAN_ID]);
 
 		if (id >= VXLAN_N_VID) {
-			NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_VXLAN_ID],
+			NL_SET_ERR_MSG_ATTR(extack, data[IFLA_VXLAN_ID],
 					    "VXLAN ID must be lower than 16777216");
 			return -ERANGE;
 		}
@@ -3155,7 +3155,7 @@ static int vxlan_validate(struct nlattr *tb[], struct nlattr *data[],
 			= nla_data(data[IFLA_VXLAN_PORT_RANGE]);
 
 		if (ntohs(p->high) < ntohs(p->low)) {
-			NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_VXLAN_PORT_RANGE],
+			NL_SET_ERR_MSG_ATTR(extack, data[IFLA_VXLAN_PORT_RANGE],
 					    "Invalid source port range");
 			return -EINVAL;
 		}
@@ -3165,7 +3165,7 @@ static int vxlan_validate(struct nlattr *tb[], struct nlattr *data[],
 		enum ifla_vxlan_df df = nla_get_u8(data[IFLA_VXLAN_DF]);
 
 		if (df < 0 || df > VXLAN_DF_MAX) {
-			NL_SET_ERR_MSG_ATTR(extack, tb[IFLA_VXLAN_DF],
+			NL_SET_ERR_MSG_ATTR(extack, data[IFLA_VXLAN_DF],
 					    "Invalid DF attribute");
 			return -EINVAL;
 		}
-- 
2.26.1