public inbox for kernel-janitors@vger.kernel.org
 help / color / mirror / Atom feed
From: Colin King <colin.king@canonical.com>
To: Peter Huewe <peterhuewe@gmx.de>,
	Marcel Selhorst <tpmdd@selhorst.net>,
	Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
	Jason Gunthorpe <jgunthorpe@obsidianresearch.com>,
	tpmdd-devel@lists.sourceforge.net
Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH] tpm2: fix off-by-one comparison and out-of-bounds read error
Date: Mon, 20 Mar 2017 14:23:36 +0000	[thread overview]
Message-ID: <20170320142336.10997-1-colin.king@canonical.com> (raw)

From: Colin Ian King <colin.king@canonical.com>

The comparison of an out of range index into space->context_tbl is
off-by-one and should be using >= rather than > in the comparison.

Detected by CoverityScan, CID#1419694 ("Out-of-bounds read")

Fixes: 849246e7ce9ce ("tpm2: add session handle context saving and restoring to the space code")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 drivers/char/tpm/tpm2-space.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/char/tpm/tpm2-space.c b/drivers/char/tpm/tpm2-space.c
index d36d81e07076..009934269514 100644
--- a/drivers/char/tpm/tpm2-space.c
+++ b/drivers/char/tpm/tpm2-space.c
@@ -229,7 +229,7 @@ static bool tpm2_map_to_phandle(struct tpm_space *space, void *handle)
 	int i;
 
 	i = 0xFFFFFF - (vhandle & 0xFFFFFF);
-	if (i > ARRAY_SIZE(space->context_tbl) || !space->context_tbl[i])
+	if (i >= ARRAY_SIZE(space->context_tbl) || !space->context_tbl[i])
 		return false;
 
 	phandle = space->context_tbl[i];
-- 
2.11.0


             reply	other threads:[~2017-03-20 14:23 UTC|newest]

Thread overview: 9+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-03-20 14:23 Colin King [this message]
2017-03-22 11:42 ` [PATCH] tpm2: fix off-by-one comparison and out-of-bounds read error Jarkko Sakkinen
2017-03-22 11:45   ` Colin Ian King
2017-03-22 13:12     ` Dan Carpenter
2017-03-23 15:53       ` Jarkko Sakkinen
2017-03-23 16:23         ` Jarkko Sakkinen
2017-03-23 16:42         ` Dan Carpenter
2017-03-23 18:12           ` Jarkko Sakkinen
2017-03-23 15:51     ` Jarkko Sakkinen

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20170320142336.10997-1-colin.king@canonical.com \
    --to=colin.king@canonical.com \
    --cc=jarkko.sakkinen@linux.intel.com \
    --cc=jgunthorpe@obsidianresearch.com \
    --cc=kernel-janitors@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=peterhuewe@gmx.de \
    --cc=tpmdd-devel@lists.sourceforge.net \
    --cc=tpmdd@selhorst.net \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox