diff options
Diffstat (limited to 'package/glibc/2.19/0001-CVE-2014-7817.patch')
| -rw-r--r-- | package/glibc/2.19/0001-CVE-2014-7817.patch | 173 |
1 files changed, 0 insertions, 173 deletions
diff --git a/package/glibc/2.19/0001-CVE-2014-7817.patch b/package/glibc/2.19/0001-CVE-2014-7817.patch deleted file mode 100644 index cd20c42c2..000000000 --- a/package/glibc/2.19/0001-CVE-2014-7817.patch +++ /dev/null @@ -1,173 +0,0 @@ -Patch from https://bugzilla.redhat.com/show_bug.cgi?id=1157689 - -Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar> - -WARNING !!! WARNING !!! WARNING !!! WARNING !!! WARNING !!! WARNING !!! -EMBARGOED !!! EMBARGOED !!! EMARGOED !!! EMBARGOED !!! EMBARGOED !!! -SECURITY !!! SECURITY !!! SECURITY !!! SECURITY !!! SECURITY !!! - -CVE-2014-7817: - -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 parse_arith(). The patch also hardens parse_backticks() and -parse_comm() to check for WRDE_NOCMD flag and return an error instead -of ever running a shell. - -We expand the testsuite and add 3 new regression tests of roughtly -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, 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. - -2014-10-27 Carlos O'Donell <carlos@redhat.com> - - * wordexp-test.c (__dso_handle): Add prototype. - (__register_atfork): Likewise. - (__app_register_atfork): New function. - (registered_forks): New global. - (register_fork): New function. - (test_case): Add 3 new tests for WRDE_CMDSUB. - (main): Call __app_register_atfork. - (testit): If WRDE_NOCMD set registered_forks to zero, run test, and - if fork count is non-zero fail the test. - * posix/wordexp.c (parse_arith): Return WRDE_NOCMD if WRDE_NOCMD flag - is set and parsing '`'. - (parse_comm): Return WRDE_NOCMD if WRDE_NOCMD flag is set. - (parse_backtick): Return WRDE_NOCMD if WRDE_NOCMD flag is set and - parsing '`'. - -diff --git a/posix/wordexp-test.c b/posix/wordexp-test.c -index 4957006..5ce2a1b 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..d6a158f 100644 ---- a/posix/wordexp.c -+++ b/posix/wordexp.c -@@ -693,6 +693,12 @@ parse_arith (char **word, size_t *word_length, size_t *max_length, - break; - - case '`': -+ if (flags & WRDE_NOCMD) -+ { -+ free (expr); -+ return WRDE_NOCMD; -+ } -+ - (*offset)++; - error = parse_backtick (&expr, &expr_length, &expr_maxlen, - words, offset, flags, NULL, NULL, NULL); -@@ -1144,6 +1150,10 @@ parse_comm (char **word, size_t *word_length, size_t *max_length, - size_t comm_maxlen; - char *comm = w_newword (&comm_length, &comm_maxlen); - -+ /* Do nothing if command substitution should not succeed. */ -+ if (flags & WRDE_NOCMD) -+ return WRDE_CMDSUB; -+ - for (; words[*offset]; ++(*offset)) - { - switch (words[*offset]) -@@ -2121,6 +2131,9 @@ parse_backtick (char **word, size_t *word_length, size_t *max_length, - switch (words[*offset]) - { - case '`': -+ if (flags & WRDE_NOCMD) -+ return WRDE_NOCMD; -+ - /* Go -- give the script to the shell */ - error = exec_comm (comm, word, word_length, max_length, flags, - pwordexp, ifs, ifs_white); |