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@@ -1,174 +0,0 @@
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-From https://bugzilla.redhat.com/show_bug.cgi?id=1157689
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-Modified for eglibc.
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-
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-Signed-off-by: Gustavo Zacarias <gustavo@zacarias.com.ar>
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-
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-WARNING !!! WARNING !!! WARNING !!! WARNING !!! WARNING !!! WARNING !!!
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-EMBARGOED !!! EMBARGOED !!! EMARGOED !!! EMBARGOED !!! EMBARGOED !!!
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-SECURITY !!! SECURITY !!! SECURITY !!! SECURITY !!! SECURITY !!!
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-
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-CVE-2014-7817:
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-
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-The function wordexp() fails to properly handle the WRDE_NOCMD
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-flag when processing arithmetic inputs in the form of "$((... ``))"
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-where "..." can be anything valid. The backticks in the arithmetic
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-epxression are evaluated by in a shell even if WRDE_NOCMD forbade
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-command substitution. This allows an attacker to attempt to pass
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-dangerous commands via constructs of the above form, and bypass
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-the WRDE_NOCMD flag. This patch fixes this by checking for WRDE_NOCMD
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-in parse_arith(). The patch also hardens parse_backticks() and
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-parse_comm() to check for WRDE_NOCMD flag and return an error instead
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-of ever running a shell.
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-
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-We expand the testsuite and add 3 new regression tests of roughtly
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-the same form but with a couple of nested levels.
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-
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-On top of the 3 new tests we add fork validation to the WRDE_NOCMD
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-testing. If any forks are detected during the execution of a wordexp()
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-call with WRDE_NOCMD, the test is marked as failed. This is slightly
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-heuristic since vfork might be used, but it provides a higher level
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-of assurance that no shells were executed as part of command substitution
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-with WRDE_NOCMD in effect. In addition it doesn't require libpthread or
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-libdl, instead we use the public implementation namespace function
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-__register_atfork (already part of the public ABI for libpthread).
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-
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-Tested on x86_64 with no regressions.
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-
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-2014-10-27 Carlos O'Donell <carlos@redhat.com>
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-
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- * wordexp-test.c (__dso_handle): Add prototype.
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- (__register_atfork): Likewise.
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- (__app_register_atfork): New function.
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- (registered_forks): New global.
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- (register_fork): New function.
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- (test_case): Add 3 new tests for WRDE_CMDSUB.
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- (main): Call __app_register_atfork.
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- (testit): If WRDE_NOCMD set registered_forks to zero, run test, and
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- if fork count is non-zero fail the test.
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- * posix/wordexp.c (parse_arith): Return WRDE_NOCMD if WRDE_NOCMD flag
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- is set and parsing '`'.
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- (parse_comm): Return WRDE_NOCMD if WRDE_NOCMD flag is set.
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- (parse_backtick): Return WRDE_NOCMD if WRDE_NOCMD flag is set and
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- parsing '`'.
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-
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-diff --git a/posix/wordexp-test.c b/posix/wordexp-test.c
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-index 4957006..5ce2a1b 100644
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---- a/libc/posix/wordexp-test.c
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-+++ b/libc/posix/wordexp-test.c
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-@@ -27,6 +27,25 @@
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-
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- #define IFS " \n\t"
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-
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-+extern void *__dso_handle __attribute__ ((__weak__, __visibility__ ("hidden")));
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-+extern int __register_atfork (void (*) (void), void (*) (void), void (*) (void), void *);
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-+
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-+static int __app_register_atfork (void (*prepare) (void), void (*parent) (void), void (*child) (void))
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-+{
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-+ return __register_atfork (prepare, parent, child,
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-+ &__dso_handle == NULL ? NULL : __dso_handle);
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-+}
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-+
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-+/* Number of forks seen. */
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-+static int registered_forks;
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-+
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-+/* For each fork increment the fork count. */
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-+static void
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-+register_fork (void)
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-+{
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-+ registered_forks++;
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-+}
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-+
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- struct test_case_struct
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- {
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- int retval;
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-@@ -206,6 +225,12 @@ struct test_case_struct
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- { WRDE_SYNTAX, NULL, "$((2+))", 0, 0, { NULL, }, IFS },
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- { WRDE_SYNTAX, NULL, "`", 0, 0, { NULL, }, IFS },
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- { WRDE_SYNTAX, NULL, "$((010+4+))", 0, 0, { NULL }, IFS },
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-+ /* Test for CVE-2014-7817. We test 3 combinations of command
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-+ substitution inside an arithmetic expression to make sure that
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-+ no commands are executed and error is returned. */
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-+ { WRDE_CMDSUB, NULL, "$((`echo 1`))", WRDE_NOCMD, 0, { NULL, }, IFS },
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-+ { WRDE_CMDSUB, NULL, "$((1+`echo 1`))", WRDE_NOCMD, 0, { NULL, }, IFS },
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-+ { WRDE_CMDSUB, NULL, "$((1+$((`echo 1`))))", WRDE_NOCMD, 0, { NULL, }, IFS },
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-
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- { -1, NULL, NULL, 0, 0, { NULL, }, IFS },
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- };
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-@@ -258,6 +283,15 @@ main (int argc, char *argv[])
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- return -1;
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- }
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-
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-+ /* If we are not allowed to do command substitution, we install
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-+ fork handlers to verify that no forks happened. No forks should
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-+ happen at all if command substitution is disabled. */
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-+ if (__app_register_atfork (register_fork, NULL, NULL) != 0)
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-+ {
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-+ printf ("Failed to register fork handler.\n");
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-+ return -1;
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-+ }
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-+
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- for (test = 0; test_case[test].retval != -1; test++)
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- if (testit (&test_case[test]))
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- ++fail;
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-@@ -367,6 +401,9 @@ testit (struct test_case_struct *tc)
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-
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- printf ("Test %d (%s): ", ++tests, tc->words);
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-
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-+ if (tc->flags & WRDE_NOCMD)
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-+ registered_forks = 0;
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-+
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- if (tc->flags & WRDE_APPEND)
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- {
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- /* initial wordexp() call, to be appended to */
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-@@ -378,6 +415,13 @@ testit (struct test_case_struct *tc)
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- }
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- retval = wordexp (tc->words, &we, tc->flags);
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-
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-+ if ((tc->flags & WRDE_NOCMD)
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-+ && (registered_forks > 0))
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-+ {
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-+ printf ("FAILED fork called for WRDE_NOCMD\n");
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-+ return 1;
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-+ }
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-+
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- if (tc->flags & WRDE_DOOFFS)
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- start_offs = sav_we.we_offs;
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-
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-diff --git a/posix/wordexp.c b/posix/wordexp.c
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-index b6b65dd..d6a158f 100644
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---- a/libc/posix/wordexp.c
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-+++ b/libc/posix/wordexp.c
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-@@ -693,6 +693,12 @@ parse_arith (char **word, size_t *word_length, size_t *max_length,
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- break;
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-
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- case '`':
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-+ if (flags & WRDE_NOCMD)
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-+ {
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-+ free (expr);
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-+ return WRDE_NOCMD;
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-+ }
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-+
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- (*offset)++;
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- error = parse_backtick (&expr, &expr_length, &expr_maxlen,
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- words, offset, flags, NULL, NULL, NULL);
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-@@ -1144,6 +1150,10 @@ parse_comm (char **word, size_t *word_length, size_t *max_length,
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- size_t comm_maxlen;
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- char *comm = w_newword (&comm_length, &comm_maxlen);
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-
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-+ /* Do nothing if command substitution should not succeed. */
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-+ if (flags & WRDE_NOCMD)
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-+ return WRDE_CMDSUB;
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-+
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- for (; words[*offset]; ++(*offset))
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- {
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- switch (words[*offset])
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-@@ -2121,6 +2131,9 @@ parse_backtick (char **word, size_t *word_length, size_t *max_length,
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- switch (words[*offset])
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- {
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- case '`':
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-+ if (flags & WRDE_NOCMD)
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-+ return WRDE_NOCMD;
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-+
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- /* Go -- give the script to the shell */
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- error = exec_comm (comm, word, word_length, max_length, flags,
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- pwordexp, ifs, ifs_white);
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