diff options
| -rw-r--r-- | ChangeLog | 13 | ||||
| -rw-r--r-- | elf/dl-tunables.c | 87 | ||||
| -rw-r--r-- | elf/dl-tunables.list | 1 |
3 files changed, 23 insertions, 78 deletions
@@ -1,3 +1,16 @@ +2016-01-10 Siddhesh Poyarekar <siddhesh@sourceware.org> + + * elf/dl-tunables.c (tunables_unsetenv): Remove function. + (min_strlen): Likewise. + (disable_tunable): Likewise. + (maybe_disable_malloc_check): Rename to + maybe_enable_malloc_check. + (maybe_enable_malloc_check): Enable glibc.malloc.check tunable + if /etc/suid-debug file exists. + (__tunables_init): Update caller. + * elf/dl-tunables.list (glibc.malloc.check): Don't mark as + secure. + 2016-01-10 Torvald Riegel <triegel@redhat.com> * nptl/DESIGN-rwlock.txt: Remove. diff --git a/elf/dl-tunables.c b/elf/dl-tunables.c index c20a477eae..e0119d17ed 100644 --- a/elf/dl-tunables.c +++ b/elf/dl-tunables.c @@ -100,34 +100,6 @@ get_next_env (char **envp, char **name, size_t *namelen, char **val) return NULL; } -static int -tunables_unsetenv (char **ep, const char *name) -{ - while (*ep != NULL) - { - size_t cnt = 0; - - while ((*ep)[cnt] == name[cnt] && name[cnt] != '\0') - ++cnt; - - if (name[cnt] == '\0' && (*ep)[cnt] == '=') - { - /* Found it. Remove this pointer by moving later ones to - the front. */ - char **dp = ep; - - do - dp[0] = dp[1]; - while (*dp++); - /* Continue the loop in case NAME appears again. */ - } - else - ++ep; - } - - return 0; -} - /* A stripped down strtoul-like implementation for very early use. It does not set errno if the result is outside bounds because it gets called before errno may have been set up. */ @@ -316,57 +288,18 @@ parse_tunables (char *tunestr) } #endif -static size_t -min_strlen (const char *s) -{ - size_t i = 0; - while (*s++ != '\0') - i++; - - return i; -} - -/* Disable a tunable if it is set. */ -static void -disable_tunable (tunable_id_t id, char **envp) -{ - const char *env_alias = tunable_list[id].env_alias; - - if (env_alias != NULL) - tunables_unsetenv (envp, tunable_list[id].env_alias); - -#if TUNABLES_FRONTEND == TUNABLES_FRONTEND_valstring - char *tunable = getenv (GLIBC_TUNABLES); - const char *cmp = tunable_list[id].name; - const size_t len = min_strlen (cmp); - - while (tunable && *tunable != '\0' && *tunable != ':') - { - if (is_name (tunable, cmp)) - { - tunable += len; - /* Overwrite the = and the value with colons. */ - while (*tunable != '\0' && *tunable != ':') - *tunable++ = ':'; - break; - } - tunable++; - } -#endif -} - -/* Disable the glibc.malloc.check tunable in SETUID/SETGID programs unless - the system administrator overrides it by creating the /etc/suid-debug - file. This is a special case where we want to conditionally enable/disable - a tunable even for setuid binaries. We use the special version of access() - to avoid setting ERRNO, which is a TLS variable since TLS has not yet been - set up. */ +/* Enable the glibc.malloc.check tunable in SETUID/SETGID programs only when + the system administrator has created the /etc/suid-debug file. This is a + special case where we want to conditionally enable/disable a tunable even + for setuid binaries. We use the special version of access() to avoid + setting ERRNO, which is a TLS variable since TLS has not yet been set + up. */ static inline void __always_inline -maybe_disable_malloc_check (void) +maybe_enable_malloc_check (void) { - if (__libc_enable_secure && __access_noerrno ("/etc/suid-debug", F_OK) != 0) - disable_tunable (TUNABLE_ENUM_NAME(glibc, malloc, check), __environ); + if (__access_noerrno ("/etc/suid-debug", F_OK) == 0) + tunable_list[TUNABLE_ENUM_NAME(glibc, malloc, check)].is_secure = true; } /* Initialize the tunables list from the environment. For now we only use the @@ -379,7 +312,7 @@ __tunables_init (char **envp) char *envval = NULL; size_t len = 0; - maybe_disable_malloc_check (); + maybe_enable_malloc_check (); while ((envp = get_next_env (envp, &envname, &len, &envval)) != NULL) { diff --git a/elf/dl-tunables.list b/elf/dl-tunables.list index cbd1f4fb4a..d8cd912559 100644 --- a/elf/dl-tunables.list +++ b/elf/dl-tunables.list @@ -31,7 +31,6 @@ glibc { minval: 0 maxval: 3 env_alias: MALLOC_CHECK_ - is_secure: true } top_pad { type: SIZE_T |