From: Ben Hutchings <ben@decadent.org.uk>
Date: Tue, 26 Aug 2014 07:34:44 +0000 (-0700)
Subject: drivers/base: Fix length checks in create_syslog_header()/dev_vprintk_emit()
X-Git-Tag: fixes-for-v3.18-merge-window~13^2~9
X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=655e5b7c031e84cf8c07cfd6a5944ce53cba1add;p=pandora-kernel.git

drivers/base: Fix length checks in create_syslog_header()/dev_vprintk_emit()

snprintf() returns the number of bytes that could have been written
(excluding the null), not the actual number of bytes written.  Given a
long enough subsystem or device name, these functions will advance
beyond the end of the on-stack buffer in dev_vprintk_exit(), resulting
in an information leak or stack corruption.  I don't know whether such
a long name is currently possible.

In case snprintf() returns a value >= the buffer size, do not add
structured logging information.  Also WARN if this happens, so we can
fix the driver or increase the buffer size.

Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

Reading git-diff-tree failed