This is a note to let you know that I've just added the patch titled
509: fix printing uninitialized stack memory when OID is empty
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
509-fix-printing-uninitialized-stack-memory-when-oid-is-empty.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Fri Feb 23 11:48:40 CET 2018
From: Eric Biggers <ebiggers3@xxxxxxxxx>
Date: Fri, 8 Dec 2017 15:13:28 +0000
Subject: 509: fix printing uninitialized stack memory when OID is empty
From: Eric Biggers <ebiggers3@xxxxxxxxx>
[ Upstream commit 8dfd2f22d3bf3ab7714f7495ad5d897b8845e8c1 ]
Callers of sprint_oid() do not check its return value before printing
the result. In the case where the OID is zero-length, -EBADMSG was
being returned without anything being written to the buffer, resulting
in uninitialized stack memory being printed. Fix this by writing
"(bad)" to the buffer in the cases where -EBADMSG is returned.
Fixes: 4f73175d0375 ("X.509: Add utility functions to render OIDs as strings")
Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
lib/oid_registry.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
--- a/lib/oid_registry.c
+++ b/lib/oid_registry.c
@@ -116,7 +116,7 @@ int sprint_oid(const void *data, size_t
int count;
if (v >= end)
- return -EBADMSG;
+ goto bad;
n = *v++;
ret = count = snprintf(buffer, bufsize, "%u.%u", n / 40, n % 40);
@@ -134,7 +134,7 @@ int sprint_oid(const void *data, size_t
num = n & 0x7f;
do {
if (v >= end)
- return -EBADMSG;
+ goto bad;
n = *v++;
num <<= 7;
num |= n & 0x7f;
@@ -148,6 +148,10 @@ int sprint_oid(const void *data, size_t
}
return ret;
+
+bad:
+ snprintf(buffer, bufsize, "(bad)");
+ return -EBADMSG;
}
EXPORT_SYMBOL_GPL(sprint_oid);
Patches currently in stable-queue which might be from ebiggers3@xxxxxxxxx are
queue-4.9/509-fix-printing-uninitialized-stack-memory-when-oid-is-empty.patch