perf/ftrace: Fix paranoid level for enabling function tracer (CVE-2013-2930)

svn path=/dists/trunk/linux/; revision=20800

debian/changelog

@@ -12,6 +12,8 @@ linux (3.12-1~exp1) UNRELEASED; urgency=low
     size
   * [arm,x86,s390,s390x] Introduce linux-compiler meta-packages to allow use
     of foreign linux-headers packages with a native multilib compiler
+  * perf/ftrace: Fix paranoid level for enabling function tracer
+    (CVE-2013-2930)
 
   [ Thorsten Glaser ]
   * Update m68k config (Closes: #728392):

debian/patches/bugfix/all/perf-ftrace-Fix-paranoid-level-for-enabling-function.patch

@@ -0,0 +1,42 @@
+From: Steven Rostedt <rostedt@goodmis.org>
+Date: Tue, 5 Nov 2013 12:51:11 -0500
+Subject: perf/ftrace: Fix paranoid level for enabling function tracer
+Origin: https://git.kernel.org/cgit/linux/kernel/git/rostedt/linux-trace.git/commit?id=d1356abac98cce8e7765186f8093da1442d74d1d
+
+The current default perf paranoid level is "1" which has
+"perf_paranoid_kernel()" return false, and giving any operations that
+use it, access to normal users. Unfortunately, this includes function
+tracing and normal users should not be allowed to enable function
+tracing by default.
+
+The proper level is defined at "-1" (full perf access), which
+"perf_paranoid_tracepoint_raw()" will only give access to. Use that
+check instead for enabling function tracing.
+
+Reported-by: Dave Jones <davej@redhat.com>
+Reported-by: Vince Weaver <vincent.weaver@maine.edu>
+Cc: Peter Zijlstra <peterz@infradead.org>
+Cc: Ingo Molnar <mingo@kernel.org>
+Cc: Jiri Olsa <jolsa@redhat.com>
+Cc: Frederic Weisbecker <fweisbec@gmail.com>
+Cc: stable@vger.kernel.org # 3.4+
+CVE: CVE-2013-2930
+Fixes: ced39002f5ea ("ftrace, perf: Add support to use function tracepoint in perf")
+Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
+---
+ kernel/trace/trace_event_perf.c | 2 +-
+ 1 file changed, 1 insertion(+), 1 deletion(-)
+
+diff --git a/kernel/trace/trace_event_perf.c b/kernel/trace/trace_event_perf.c
+index 80c36bc..78e27e3 100644
+--- a/kernel/trace/trace_event_perf.c
++++ b/kernel/trace/trace_event_perf.c
+@@ -26,7 +26,7 @@ static int perf_trace_event_perm(struct ftrace_event_call *tp_event,
+ {
+ 	/* The ftrace function trace is allowed only for root. */
+ 	if (ftrace_event_is_function(tp_event) &&
+-	    perf_paranoid_kernel() && !capable(CAP_SYS_ADMIN))
++	    perf_paranoid_tracepoint_raw() && !capable(CAP_SYS_ADMIN))
+ 		return -EPERM;
+ 
+ 	/* No tracing, just counting, so no obvious leak */

debian/patches/series

@@ -76,3 +76,4 @@ bugfix/all/kbuild-use-nostdinc-in-compile-tests.patch
 debian/add-sysctl-to-disallow-unprivileged-CLONE_NEWUSER-by-default.patch
 bugfix/all/UAPI-include-asm-byteorder.h-in-linux-raid-md_p.h.patch
 bugfix/all/CVE-2013-4348.patch
+bugfix/all/perf-ftrace-Fix-paranoid-level-for-enabling-function.patch