lkml.org 
[lkml]   [2020]   [Jun]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH 4.14 066/190] Smack: slab-out-of-bounds in vsscanf
Date
From: Casey Schaufler <casey@schaufler-ca.com>

commit 84e99e58e8d1e26f04c097f4266e431a33987f36 upstream.

Add barrier to soob. Return -EOVERFLOW if the buffer
is exceeded.

Suggested-by: Hillf Danton <hdanton@sina.com>
Reported-by: syzbot+bfdd4a2f07be52351350@syzkaller.appspotmail.com
Signed-off-by: Casey Schaufler <casey@schaufler-ca.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
security/smack/smackfs.c | 10 ++++++++++
1 file changed, 10 insertions(+)

--- a/security/smack/smackfs.c
+++ b/security/smack/smackfs.c
@@ -906,11 +906,21 @@ static ssize_t smk_set_cipso(struct file
else
rule += strlen(skp->smk_known) + 1;

+ if (rule > data + count) {
+ rc = -EOVERFLOW;
+ goto out;
+ }
+
ret = sscanf(rule, "%d", &maplevel);
if (ret != 1 || maplevel > SMACK_CIPSO_MAXLEVEL)
goto out;

rule += SMK_DIGITLEN;
+ if (rule > data + count) {
+ rc = -EOVERFLOW;
+ goto out;
+ }
+
ret = sscanf(rule, "%d", &catlen);
if (ret != 1 || catlen > SMACK_CIPSO_MAXCATNUM)
goto out;

\
 
 \ /
  Last update: 2020-06-19 16:49    [W:0.535 / U:0.456 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site