~ruther/guix-local

26804e1351a86bfcde1b8bebeb984b9c79e6fe6f — Mark H Weaver 11 years ago 8cbb67e
gnu: glibc: Add fixes for CVE-2014-7817 and CVE-2012-3406.

* gnu/packages/patches/glibc-CVE-2012-3406.patch,
  gnu/packages/patches/glibc-CVE-2014-7817.patch: New files.
* gnu-system.am (dist_patch_DATA): Add them.
* gnu/packages/base.scm (glibc): Add patches.
M gnu-system.am => gnu-system.am +2 -0
@@ 362,6 362,8 @@ dist_patch_DATA =						\
  gnu/packages/patches/glib-tests-prlimit.patch			\
  gnu/packages/patches/glib-tests-timer.patch			\
  gnu/packages/patches/glib-tests-gapplication.patch		\
  gnu/packages/patches/glibc-CVE-2012-3406.patch		\
  gnu/packages/patches/glibc-CVE-2014-7817.patch		\
  gnu/packages/patches/glibc-bootstrap-system.patch		\
  gnu/packages/patches/glibc-ldd-x86_64.patch			\
  gnu/packages/patches/gnunet-fix-scheduler.patch		\

M gnu/packages/base.scm => gnu/packages/base.scm +3 -1
@@ 375,7 375,9 @@ included.")
                (("use_ldconfig=yes")
                 "use_ldconfig=no")))
            (modules '((guix build utils)))
            (patches (list (search-patch "glibc-ldd-x86_64.patch")))))
            (patches (list (search-patch "glibc-CVE-2014-7817.patch")
                           (search-patch "glibc-CVE-2012-3406.patch")
                           (search-patch "glibc-ldd-x86_64.patch")))))
   (build-system gnu-build-system)

   ;; Glibc's <limits.h> refers to <linux/limit.h>, for instance, so glibc

A gnu/packages/patches/glibc-CVE-2012-3406.patch => gnu/packages/patches/glibc-CVE-2012-3406.patch +282 -0
@@ 0,0 1,282 @@
Fix CVE-2012-3406: Stack overflow in vfprintf [BZ #16617]

Note: Here the ChangeLog and NEWS updates are removed from Jeff's
      patch, since they depend on other earlier commits.

From: Jeff Law <law@redhat.com>
Date: Mon, 15 Dec 2014 09:09:32 +0000 (+0100)
Subject: CVE-2012-3406: Stack overflow in vfprintf [BZ #16617]
X-Git-Url: https://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff_plain;h=a3a1f4163c4d0f9a36056c8640661a88674ae8a2

CVE-2012-3406: Stack overflow in vfprintf [BZ #16617]

A larger number of format specifiers coudld cause a stack overflow,
potentially allowing to bypass _FORTIFY_SOURCE format string
protection.

(cherry picked from commit a5357b7ce2a2982c5778435704bcdb55ce3667a0)
(cherry picked from commit ae61fc7b33d9d99d2763c16de8275227dc9748ba)

Conflicts:
	NEWS
---

diff --git a/stdio-common/Makefile b/stdio-common/Makefile
index 5f8e534..e5e45b6 100644
--- a/stdio-common/Makefile
+++ b/stdio-common/Makefile
@@ -57,7 +57,7 @@ tests := tstscanf test_rdwr test-popen tstgetln test-fseek \
 	 bug19 bug19a tst-popen2 scanf13 scanf14 scanf15 bug20 bug21 bug22 \
 	 scanf16 scanf17 tst-setvbuf1 tst-grouping bug23 bug24 \
 	 bug-vfprintf-nargs tst-long-dbl-fphex tst-fphex-wide tst-sprintf3 \
-	 bug25 tst-printf-round bug26
+	 bug25 tst-printf-round bug23-2 bug23-3 bug23-4 bug26
 
 test-srcs = tst-unbputc tst-printf
 
diff --git a/stdio-common/bug23-2.c b/stdio-common/bug23-2.c
new file mode 100644
index 0000000..9e0cfe6
--- /dev/null
+++ b/stdio-common/bug23-2.c
@@ -0,0 +1,70 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+static const char expected[] = "\
+\n\
+a\n\
+abbcd55\
+\n\
+a\n\
+abbcd55\
+\n\
+a\n\
+abbcd55\
+\n\
+a\n\
+abbcd55\
+\n\
+a\n\
+abbcd55\
+\n\
+a\n\
+abbcd55\
+\n\
+a\n\
+abbcd55\
+\n\
+a\n\
+abbcd55\
+\n\
+a\n\
+abbcd55\
+\n\
+a\n\
+abbcd55\
+\n\
+a\n\
+abbcd55\
+\n\
+a\n\
+abbcd55\
+\n\
+a\n\
+abbcd55%%%%%%%%%%%%%%%%%%%%%%%%%%\n";
+
+static int
+do_test (void)
+{
+  char *buf = malloc (strlen (expected) + 1);
+  snprintf (buf, strlen (expected) + 1,
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+	    "%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%\n",
+	    "a", "b", "c", "d", 5);
+  return strcmp (buf, expected) != 0;
+}
+
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
diff --git a/stdio-common/bug23-3.c b/stdio-common/bug23-3.c
new file mode 100644
index 0000000..57c8cef
--- /dev/null
+++ b/stdio-common/bug23-3.c
@@ -0,0 +1,50 @@
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+int
+do_test (void)
+{
+  size_t instances = 16384;
+#define X0 "\n%1$s\n" "%1$s" "%2$s" "%2$s" "%3$s" "%4$s" "%5$d" "%5$d"
+  const char *item = "\na\nabbcd55";
+#define X3 X0 X0 X0 X0 X0 X0 X0 X0
+#define X6 X3 X3 X3 X3 X3 X3 X3 X3
+#define X9 X6 X6 X6 X6 X6 X6 X6 X6
+#define X12 X9 X9 X9 X9 X9 X9 X9 X9
+#define X14 X12 X12 X12 X12
+#define TRAILER "%%%%%%%%%%%%%%%%%%%%%%%%%%"
+#define TRAILER2 TRAILER TRAILER
+  size_t length = instances * strlen (item) + strlen (TRAILER) + 1;
+
+  char *buf = malloc (length + 1);
+  snprintf (buf, length + 1,
+	    X14 TRAILER2 "\n",
+	    "a", "b", "c", "d", 5);
+
+  const char *p = buf;
+  size_t i;
+  for (i = 0; i < instances; ++i)
+    {
+      const char *expected;
+      for (expected = item; *expected; ++expected)
+	{
+	  if (*p != *expected)
+	    {
+	      printf ("mismatch at offset %zu (%zu): expected %d, got %d\n",
+		      (size_t) (p - buf), i, *expected & 0xFF, *p & 0xFF);
+	      return 1;
+	    }
+	  ++p;
+	}
+    }
+  if (strcmp (p, TRAILER "\n") != 0)
+    {
+      printf ("mismatch at trailer: [%s]\n", p);
+      return 1;
+    }
+  free (buf);
+  return 0;
+}
+#define TEST_FUNCTION do_test ()
+#include "../test-skeleton.c"
diff --git a/stdio-common/bug23-4.c b/stdio-common/bug23-4.c
new file mode 100644
index 0000000..a478564
--- /dev/null
+++ b/stdio-common/bug23-4.c
@@ -0,0 +1,31 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/resource.h>
+
+#define LIMIT 1000000
+
+int
+main (void)
+{
+  struct rlimit lim;
+  getrlimit (RLIMIT_STACK, &lim);
+  lim.rlim_cur = 1048576;
+  setrlimit (RLIMIT_STACK, &lim);
+  char *fmtstr = malloc (4 * LIMIT + 1);
+  if (fmtstr == NULL)
+    abort ();
+  char *output = malloc (LIMIT + 1);
+  if (output == NULL)
+    abort ();
+  for (size_t i = 0; i < LIMIT; i++)
+    memcpy (fmtstr + 4 * i, "%1$d", 4);
+  fmtstr[4 * LIMIT] = '\0';
+  int ret = snprintf (output, LIMIT + 1, fmtstr, 0);
+  if (ret != LIMIT)
+    abort ();
+  for (size_t i = 0; i < LIMIT; i++)
+    if (output[i] != '0')
+      abort ();
+  return 0;
+}
diff --git a/stdio-common/vfprintf.c b/stdio-common/vfprintf.c
index c4ff833..429a3d1 100644
--- a/stdio-common/vfprintf.c
+++ b/stdio-common/vfprintf.c
@@ -263,6 +263,12 @@ vfprintf (FILE *s, const CHAR_T *format, va_list ap)
   /* For the argument descriptions, which may be allocated on the heap.  */
   void *args_malloced = NULL;
 
+  /* For positional argument handling.  */
+  struct printf_spec *specs;
+
+  /* Track if we malloced the SPECS array and thus must free it.  */
+  bool specs_malloced = false;
+
   /* This table maps a character into a number representing a
      class.  In each step there is a destination label for each
      class.  */
@@ -1679,8 +1685,8 @@ do_positional:
     size_t nspecs = 0;
     /* A more or less arbitrary start value.  */
     size_t nspecs_size = 32 * sizeof (struct printf_spec);
-    struct printf_spec *specs = alloca (nspecs_size);
 
+    specs = alloca (nspecs_size);
     /* The number of arguments the format string requests.  This will
        determine the size of the array needed to store the argument
        attributes.  */
@@ -1721,11 +1727,39 @@ do_positional:
 	if (nspecs * sizeof (*specs) >= nspecs_size)
 	  {
 	    /* Extend the array of format specifiers.  */
+	    if (nspecs_size * 2 < nspecs_size)
+	      {
+		__set_errno (ENOMEM);
+		done = -1;
+		goto all_done;
+	      }
 	    struct printf_spec *old = specs;
-	    specs = extend_alloca (specs, nspecs_size, 2 * nspecs_size);
+	    if (__libc_use_alloca (2 * nspecs_size))
+	      specs = extend_alloca (specs, nspecs_size, 2 * nspecs_size);
+	    else
+	      {
+		nspecs_size *= 2;
+		specs = malloc (nspecs_size);
+		if (specs == NULL)
+		  {
+		    __set_errno (ENOMEM);
+		    specs = old;
+		    done = -1;
+		    goto all_done;
+		  }
+	      }
 
 	    /* Copy the old array's elements to the new space.  */
 	    memmove (specs, old, nspecs * sizeof (*specs));
+
+	    /* If we had previously malloc'd space for SPECS, then
+	       release it after the copy is complete.  */
+	    if (specs_malloced)
+	      free (old);
+
+	    /* Now set SPECS_MALLOCED if needed.  */
+	    if (!__libc_use_alloca (nspecs_size))
+	      specs_malloced = true;
 	  }
 
 	/* Parse the format specifier.  */
@@ -2046,6 +2080,8 @@ do_positional:
   }
 
 all_done:
+  if (specs_malloced)
+    free (specs);
   if (__glibc_unlikely (args_malloced != NULL))
     free (args_malloced);
   if (__glibc_unlikely (workstart != NULL))

A gnu/packages/patches/glibc-CVE-2014-7817.patch => gnu/packages/patches/glibc-CVE-2014-7817.patch +171 -0
@@ 0,0 1,171 @@
Fix CVE-2014-7817: wordexp fails to honour WRDE_NOCMD.

Note: Here the ChangeLog and NEWS updates are removed from Carlos's
      patch, since they depend on other earlier commits.

From: Carlos O'Donell <carlos@redhat.com>
Date: Wed, 19 Nov 2014 16:44:12 +0000 (-0500)
Subject: CVE-2014-7817: wordexp fails to honour WRDE_NOCMD.
X-Git-Url: https://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff_plain;h=33ceaf6187b31ea15284ac65131749e1cb68d2ae

CVE-2014-7817: wordexp fails to honour WRDE_NOCMD.

The function wordexp() fails to properly handle the WRDE_NOCMD
flag when processing arithmetic inputs in the form of "$((... ``))"
where "..." can be anything valid. The backticks in the arithmetic
epxression are evaluated by in a shell even if WRDE_NOCMD forbade
command substitution. This allows an attacker to attempt to pass
dangerous commands via constructs of the above form, and bypass
the WRDE_NOCMD flag. This patch fixes this by checking for WRDE_NOCMD
in exec_comm(), the only place that can execute a shell. All other
checks for WRDE_NOCMD are superfluous and removed.

We expand the testsuite and add 3 new regression tests of roughly
the same form but with a couple of nested levels.

On top of the 3 new tests we add fork validation to the WRDE_NOCMD
testing. If any forks are detected during the execution of a wordexp()
call with WRDE_NOCMD, the test is marked as failed. This is slightly
heuristic since vfork might be used in the future, but it provides a
higher level of assurance that no shells were executed as part of
command substitution with WRDE_NOCMD in effect. In addition it doesn't
require libpthread or libdl, instead we use the public implementation
namespace function __register_atfork (already part of the public ABI
for libpthread).

Tested on x86_64 with no regressions.

(cherry picked from commit a39208bd7fb76c1b01c127b4c61f9bfd915bfe7c)
---

diff --git a/posix/wordexp-test.c b/posix/wordexp-test.c
index 4957006..bdd65e4 100644
--- a/posix/wordexp-test.c
+++ b/posix/wordexp-test.c
@@ -27,6 +27,25 @@
 
 #define IFS " \n\t"
 
+extern void *__dso_handle __attribute__ ((__weak__, __visibility__ ("hidden")));
+extern int __register_atfork (void (*) (void), void (*) (void), void (*) (void), void *);
+
+static int __app_register_atfork (void (*prepare) (void), void (*parent) (void), void (*child) (void))
+{
+  return __register_atfork (prepare, parent, child,
+			    &__dso_handle == NULL ? NULL : __dso_handle);
+}
+
+/* Number of forks seen.  */
+static int registered_forks;
+
+/* For each fork increment the fork count.  */
+static void
+register_fork (void)
+{
+  registered_forks++;
+}
+
 struct test_case_struct
 {
   int retval;
@@ -206,6 +225,12 @@ struct test_case_struct
     { WRDE_SYNTAX, NULL, "$((2+))", 0, 0, { NULL, }, IFS },
     { WRDE_SYNTAX, NULL, "`", 0, 0, { NULL, }, IFS },
     { WRDE_SYNTAX, NULL, "$((010+4+))", 0, 0, { NULL }, IFS },
+    /* Test for CVE-2014-7817. We test 3 combinations of command
+       substitution inside an arithmetic expression to make sure that
+       no commands are executed and error is returned.  */
+    { WRDE_CMDSUB, NULL, "$((`echo 1`))", WRDE_NOCMD, 0, { NULL, }, IFS },
+    { WRDE_CMDSUB, NULL, "$((1+`echo 1`))", WRDE_NOCMD, 0, { NULL, }, IFS },
+    { WRDE_CMDSUB, NULL, "$((1+$((`echo 1`))))", WRDE_NOCMD, 0, { NULL, }, IFS },
 
     { -1, NULL, NULL, 0, 0, { NULL, }, IFS },
   };
@@ -258,6 +283,15 @@ main (int argc, char *argv[])
 	  return -1;
     }
 
+  /* If we are not allowed to do command substitution, we install
+     fork handlers to verify that no forks happened.  No forks should
+     happen at all if command substitution is disabled.  */
+  if (__app_register_atfork (register_fork, NULL, NULL) != 0)
+    {
+      printf ("Failed to register fork handler.\n");
+      return -1;
+    }
+
   for (test = 0; test_case[test].retval != -1; test++)
     if (testit (&test_case[test]))
       ++fail;
@@ -367,6 +401,9 @@ testit (struct test_case_struct *tc)
 
   printf ("Test %d (%s): ", ++tests, tc->words);
 
+  if (tc->flags & WRDE_NOCMD)
+    registered_forks = 0;
+
   if (tc->flags & WRDE_APPEND)
     {
       /* initial wordexp() call, to be appended to */
@@ -378,6 +415,13 @@ testit (struct test_case_struct *tc)
     }
   retval = wordexp (tc->words, &we, tc->flags);
 
+  if ((tc->flags & WRDE_NOCMD)
+      && (registered_forks > 0))
+    {
+	  printf ("FAILED fork called for WRDE_NOCMD\n");
+	  return 1;
+    }
+
   if (tc->flags & WRDE_DOOFFS)
       start_offs = sav_we.we_offs;
 
diff --git a/posix/wordexp.c b/posix/wordexp.c
index b6b65dd..26f3a26 100644
--- a/posix/wordexp.c
+++ b/posix/wordexp.c
@@ -893,6 +893,10 @@ exec_comm (char *comm, char **word, size_t *word_length, size_t *max_length,
   pid_t pid;
   int noexec = 0;
 
+  /* Do nothing if command substitution should not succeed.  */
+  if (flags & WRDE_NOCMD)
+    return WRDE_CMDSUB;
+
   /* Don't fork() unless necessary */
   if (!comm || !*comm)
     return 0;
@@ -2082,9 +2086,6 @@ parse_dollars (char **word, size_t *word_length, size_t *max_length,
 	    }
 	}
 
-      if (flags & WRDE_NOCMD)
-	return WRDE_CMDSUB;
-
       (*offset) += 2;
       return parse_comm (word, word_length, max_length, words, offset, flags,
 			 quoted? NULL : pwordexp, ifs, ifs_white);
@@ -2196,9 +2197,6 @@ parse_dquote (char **word, size_t *word_length, size_t *max_length,
 	  break;
 
 	case '`':
-	  if (flags & WRDE_NOCMD)
-	    return WRDE_CMDSUB;
-
 	  ++(*offset);
 	  error = parse_backtick (word, word_length, max_length, words,
 				  offset, flags, NULL, NULL, NULL);
@@ -2357,12 +2355,6 @@ wordexp (const char *words, wordexp_t *pwordexp, int flags)
 	break;
 
       case '`':
-	if (flags & WRDE_NOCMD)
-	  {
-	    error = WRDE_CMDSUB;
-	    goto do_error;
-	  }
-
 	++words_offset;
 	error = parse_backtick (&word, &word_length, &max_length, words,
 				&words_offset, flags, pwordexp, ifs,