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gnu: glibc: Add fixes for CVE-2014-7817 and CVE-2012-3406.

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* 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.
This commit is contained in:
Mark H Weaver 2014-12-30 13:57:40 -05:00
parent 8cbb67e045
commit 26804e1351
4 changed files with 458 additions and 1 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

2
gnu-system.am
View file

@ -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 \

4
gnu/packages/base.scm
View file

@ -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

282
gnu/packages/patches/glibc-CVE-2012-3406.patch Normal file
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@ -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))

171
gnu/packages/patches/glibc-CVE-2014-7817.patch Normal file
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@ -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,