[042/141] iscsi-target: fix heap buffer overflow on error

Steven Rostedt
2013-07-03T18:51:55Z

[-- Attachment #1: 0042-iscsi-target-fix-heap-buffer-overflow-on-error.patch --]
[-- Type: text/plain, Size: 2415 bytes --]

3.6.11.6 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Kees Cook <keescook@chromium.org>

[ Upstream commit cea4dcfdad926a27a18e188720efe0f2c9403456 ]

If a key was larger than 64 bytes, as checked by iscsi_check_key(), the
error response packet, generated by iscsi_add_notunderstood_response(),
would still attempt to copy the entire key into the packet, overflowing
the structure on the heap.

Remote preauthentication kernel memory corruption was possible if a
target was configured and listening on the network.

CVE-2013-2850

Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: stable@vger.kernel.org
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
drivers/target/iscsi/iscsi_target_parameters.c | 8 +++-----
drivers/target/iscsi/iscsi_target_parameters.h | 4 +++-
2 files changed, 6 insertions(+), 6 deletions(-)

diff --git a/drivers/target/iscsi/iscsi_target_parameters.c b/drivers/target/iscsi/iscsi_target_parameters.c
index 0c4760f..3282c8f 100644
--- a/drivers/target/iscsi/iscsi_target_parameters.c
+++ b/drivers/target/iscsi/iscsi_target_parameters.c
@@ -713,9 +713,9 @@ static int iscsi_add_notunderstood_response(
}
INIT_LIST_HEAD(&extra_response->er_list);

- strncpy(extra_response->key, key, strlen(key) + 1);
- strncpy(extra_response->value, NOTUNDERSTOOD,
- strlen(NOTUNDERSTOOD) + 1);
+ strlcpy(extra_response->key, key, sizeof(extra_response->key));
+ strlcpy(extra_response->value, NOTUNDERSTOOD,
+ sizeof(extra_response->value));

list_add_tail(&extra_response->er_list,
&param_list->extra_response_list);
@@ -1554,8 +1554,6 @@ int iscsi_decode_text_input(

if (phase & PHASE_SECURITY) {
if (iscsi_check_for_auth_key(key) > 0) {
- char *tmpptr = key + strlen(key);
- *tmpptr = '=';
kfree(tmpbuf);
return 1;
}
diff --git a/drivers/target/iscsi/iscsi_target_parameters.h b/drivers/target/iscsi/iscsi_target_parameters.h
index 6a37fd6..83eed65 100644
--- a/drivers/target/iscsi/iscsi_target_parameters.h
+++ b/drivers/target/iscsi/iscsi_target_parameters.h
@@ -1,8 +1,10 @@
#ifndef ISCSI_PARAMETERS_H
#define ISCSI_PARAMETERS_H

+#include <scsi/iscsi_proto.h>
+
struct iscsi_extra_response {
- char key[64];
+ char key[KEY_MAXLEN];
char value[32];
struct list_head er_list;
} ____cacheline_aligned;
--
1.7.10.4