sys-libs/glibc: avoid use-after-free in pthread

This takes a patch from upstream Bugzilla by Alexey Makhalov.
2025-08-23 07:21:14 +02:00 · 2017-01-04 18:27:48 -08:00 · 2017-01-04 18:27:48 -08:00 · 14c1461247
commit 14c1461247
parent c2e3259b65
2 changed files with 133 additions and 0 deletions
--- a/sdk_container/src/third_party/coreos-overlay/sys-libs/glibc/files/2.23/glibc-2.23-pthread-use-after-free.patch
+++ b/sdk_container/src/third_party/coreos-overlay/sys-libs/glibc/files/2.23/glibc-2.23-pthread-use-after-free.patch
@ -0,0 +1,132 @@
+diff -Naur glibc-2.22_orig/nptl/createthread.c glibc-2.22/nptl/createthread.c
+--- glibc-2.22_orig/nptl/createthread.c	2015-08-04 23:42:21.000000000 -0700
+++ glibc-2.22/nptl/createthread.c	2016-09-28 11:27:50.831206703 -0700
+@@ -25,13 +25,13 @@
+ 
+ static int
+ create_thread (struct pthread *pd, const struct pthread_attr *attr,
+-	       bool stopped_start, STACK_VARIABLES_PARMS, bool *thread_ran)
+	       bool *stopped_start, STACK_VARIABLES_PARMS, bool *thread_ran)
+ {
+   /* If the implementation needs to do some tweaks to the thread after
+      it has been created at the OS level, it can set STOPPED_START here.  */
+ 
+-  pd->stopped_start = stopped_start;
+-  if (__glibc_unlikely (stopped_start))
+  pd->stopped_start = *stopped_start;
+  if (__glibc_unlikely (*stopped_start))
+     /* We make sure the thread does not run far by forcing it to get a
+        lock.  We lock it here too so that the new thread cannot continue
+        until we tell it to.  */
+diff -Naur glibc-2.22_orig/nptl/pthread_create.c glibc-2.22/nptl/pthread_create.c
+--- glibc-2.22_orig/nptl/pthread_create.c	2015-08-04 23:42:21.000000000 -0700
+++ glibc-2.22/nptl/pthread_create.c	2016-09-28 11:31:20.839209223 -0700
+@@ -72,7 +72,7 @@
+    case it is responsible for doing its own cleanup.  */
+ 
+ static int create_thread (struct pthread *pd, const struct pthread_attr *attr,
+-			  bool stopped_start, STACK_VARIABLES_PARMS,
+			  bool *stopped_start, STACK_VARIABLES_PARMS,
+ 			  bool *thread_ran);
+ 
+ #include <createthread.c>
+@@ -633,14 +633,16 @@
+      that cares whether the thread count is correct.  */
+   atomic_increment (&__nptl_nthreads);
+ 
+  bool stopped_start = false;
+   bool thread_ran = false;
+ 
+   /* Start the thread.  */
+   if (__glibc_unlikely (report_thread_creation (pd)))
+     {
+      stopped_start = true;
+       /* Create the thread.  We always create the thread stopped
+ 	 so that it does not get far before we tell the debugger.  */
+-      retval = create_thread (pd, iattr, true, STACK_VARIABLES_ARGS,
+      retval = create_thread (pd, iattr, &stopped_start, STACK_VARIABLES_ARGS,
+ 			      &thread_ran);
+       if (retval == 0)
+ 	{
+@@ -667,7 +669,7 @@
+ 	}
+     }
+   else
+-    retval = create_thread (pd, iattr, false, STACK_VARIABLES_ARGS,
+    retval = create_thread (pd, iattr, &stopped_start, STACK_VARIABLES_ARGS,
+ 			    &thread_ran);
+ 
+   if (__glibc_unlikely (retval != 0))
+@@ -701,7 +703,8 @@
+     }
+   else
+     {
+-      if (pd->stopped_start)
+      /* do not use pd->stopped_start to avoid use after free */
+      if (stopped_start)
+ 	/* The thread blocked on this lock either because we're doing TD_CREATE
+ 	   event reporting, or for some other reason that create_thread chose.
+ 	   Now let it run free.  */
+diff -Naur glibc-2.22_orig/sysdeps/nacl/createthread.c glibc-2.22/sysdeps/nacl/createthread.c
+--- glibc-2.22_orig/sysdeps/nacl/createthread.c	2015-08-04 23:42:21.000000000 -0700
+++ glibc-2.22/sysdeps/nacl/createthread.c	2016-09-28 11:27:34.983206513 -0700
+@@ -32,12 +32,12 @@
+ 
+ static int
+ create_thread (struct pthread *pd, const struct pthread_attr *attr,
+-	       bool stopped_start, STACK_VARIABLES_PARMS, bool *thread_ran)
+	       bool *stopped_start, STACK_VARIABLES_PARMS, bool *thread_ran)
+ {
+   pd->tid = __nacl_get_tid (pd);
+ 
+-  pd->stopped_start = stopped_start;
+-  if (__glibc_unlikely (stopped_start))
+  pd->stopped_start = *stopped_start;
+  if (__glibc_unlikely (*stopped_start))
+     /* We make sure the thread does not run far by forcing it to get a
+        lock.  We lock it here too so that the new thread cannot continue
+        until we tell it to.  */
+diff -Naur glibc-2.22_orig/sysdeps/unix/sysv/linux/createthread.c glibc-2.22/sysdeps/unix/sysv/linux/createthread.c
+--- glibc-2.22_orig/sysdeps/unix/sysv/linux/createthread.c	2015-08-04 23:42:21.000000000 -0700
+++ glibc-2.22/sysdeps/unix/sysv/linux/createthread.c	2016-09-28 11:27:18.275206312 -0700
+@@ -46,7 +46,7 @@
+ 
+ static int
+ create_thread (struct pthread *pd, const struct pthread_attr *attr,
+-	       bool stopped_start, STACK_VARIABLES_PARMS, bool *thread_ran)
+	       bool *stopped_start, STACK_VARIABLES_PARMS, bool *thread_ran)
+ {
+   /* Determine whether the newly created threads has to be started
+      stopped since we have to set the scheduling parameters or set the
+@@ -54,10 +54,10 @@
+   if (attr != NULL
+       && (__glibc_unlikely (attr->cpuset != NULL)
+ 	  || __glibc_unlikely ((attr->flags & ATTR_FLAG_NOTINHERITSCHED) != 0)))
+-    stopped_start = true;
+    *stopped_start = true;
+ 
+-  pd->stopped_start = stopped_start;
+-  if (__glibc_unlikely (stopped_start))
+  pd->stopped_start = *stopped_start;
+  if (__glibc_unlikely (*stopped_start))
+     /* We make sure the thread does not run far by forcing it to get a
+        lock.  We lock it here too so that the new thread cannot continue
+        until we tell it to.  */
+@@ -117,7 +117,7 @@
+       /* Set the affinity mask if necessary.  */
+       if (attr->cpuset != NULL)
+ 	{
+-	  assert (stopped_start);
+	  assert (*stopped_start);
+ 
+ 	  res = INTERNAL_SYSCALL (sched_setaffinity, err, 3, pd->tid,
+ 				  attr->cpusetsize, attr->cpuset);
+@@ -140,7 +140,7 @@
+       /* Set the scheduling parameters.  */
+       if ((attr->flags & ATTR_FLAG_NOTINHERITSCHED) != 0)
+ 	{
+-	  assert (stopped_start);
+	  assert (*stopped_start);
+ 
+ 	  res = INTERNAL_SYSCALL (sched_setscheduler, err, 3, pd->tid,
+ 				  pd->schedpolicy, &pd->schedparam);
--- a/sdk_container/src/third_party/coreos-overlay/sys-libs/glibc/glibc-2.22-r5.ebuild
+++ b/sdk_container/src/third_party/coreos-overlay/sys-libs/glibc/glibc-2.22-r5.ebuild
@ -167,6 +167,7 @@ eblit-src_prepare-post() {
 	## COREOS: features and bug fixes missing from the Gentoo patch set.
 	epatch "${FILESDIR}"/2.23/glibc-2.23-gshadow-handle-erange.patch
 	epatch "${FILESDIR}"/2.23/glibc-2.23-c-utf8-locale.patch
+	epatch "${FILESDIR}"/2.23/glibc-2.23-pthread-use-after-free.patch

 	if use hardened ; then
 		# We don't enable these for non-hardened as the output is very terse --