main: free suid_config list after use

function                                             old     new   delta
run_applet_no_and_exit                               438     450     +12
ifupdown_main                                       2147    2149      +2
writeFileToTarball                                  1325    1326      +1
pidof_main                                           244     245      +1
last_main                                            896     897      +1
grep_main                                            779     780      +1
find_list_entry2                                     121     122      +1
tar_main                                             835     833      -2
llist_unlink                                          28      26      -2
llist_rev                                             23      21      -2
main                                                 791     782      -9
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 7/4 up/down: 19/-15)              Total: 4 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2011-05-16 12:21:31 +02:00
parent 9a296fbeab
commit 9be4702a30
3 changed files with 36 additions and 35 deletions

View File

@ -987,9 +987,13 @@ extern uint32_t option_mask32;
extern uint32_t getopt32(char **argv, const char *applet_opts, ...) FAST_FUNC;
/* Having next pointer as a first member allows easy creation
* of "llist-compatible" structs, and using llist_FOO functions
* on them.
*/
typedef struct llist_t {
char *data;
struct llist_t *link;
char *data;
} llist_t;
void llist_add_to(llist_t **old_head, void *data) FAST_FUNC;
void llist_add_to_end(llist_t **list_head, void *data) FAST_FUNC;

View File

@ -27,12 +27,13 @@
* FEATURE_INSTALLER or FEATURE_SUID will still link printf routines in. :(
*/
#include "busybox.h"
#include <assert.h>
#if !(defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__) \
|| defined(__APPLE__) \
)
# include <malloc.h> /* for mallopt */
#endif
/* Try to pull in PAGE_SIZE */
#ifdef __linux__
# include <sys/user.h>
@ -40,6 +41,9 @@
#ifdef __GNU__ /* Hurd */
# include <mach/vm_param.h>
#endif
#ifndef PAGE_SIZE
# define PAGE_SIZE (4*1024) /* guess */
#endif
/* Declare <applet>_main() */
@ -47,7 +51,6 @@
#include "applets.h"
#undef PROTOTYPES
/* Include generated applet names, pointers to <applet>_main, etc */
#include "applet_tables.h"
/* ...and if applet_tables generator says we have only one applet... */
@ -58,9 +61,9 @@
# define IF_FEATURE_INDIVIDUAL(...) __VA_ARGS__
#endif
#include "usage_compressed.h"
#if ENABLE_SHOW_USAGE && !ENABLE_FEATURE_COMPRESS_USAGE
static const char usage_messages[] ALIGN1 = UNPACKED_USAGE;
#else
@ -233,12 +236,12 @@ IF_FEATURE_SUID(static uid_t ruid;) /* real uid */
# if ENABLE_FEATURE_SUID_CONFIG
/* applets[] is const, so we have to define this "override" structure */
static struct BB_suid_config {
int m_applet;
static struct suid_config_t {
/* next ptr must be first: this struct needs to be llist-compatible */
struct suid_config_t *m_next;
struct bb_uidgid_t m_ugid;
int m_applet;
mode_t m_mode;
struct BB_suid_config *m_next;
} *suid_config;
static bool suid_cfg_readable;
@ -247,13 +250,10 @@ static bool suid_cfg_readable;
static int ingroup(uid_t u, gid_t g)
{
struct group *grp = getgrgid(g);
if (grp) {
char **mem;
for (mem = grp->gr_mem; *mem; mem++) {
struct passwd *pwd = getpwnam(*mem);
if (pwd && (pwd->pw_uid == u))
return 1;
}
@ -296,17 +296,12 @@ static const unsigned short mode_mask[] ALIGN2 = {
static void parse_config_file(void)
{
struct BB_suid_config *sct_head;
struct BB_suid_config *sct;
struct suid_config_t *sct_head;
int applet_no;
FILE *f;
const char *errmsg;
char *s;
char *e;
int i;
unsigned lc;
smallint section;
char buffer[256];
struct stat st;
ruid = getuid();
@ -327,9 +322,10 @@ static void parse_config_file(void)
section = lc = 0;
while (1) {
s = buffer;
char buffer[256];
char *s;
if (!fgets(s, sizeof(buffer), f)) { /* Are we done? */
if (!fgets(buffer, sizeof(buffer), f)) { /* Are we done? */
// Looks like bloat
//if (ferror(f)) { /* Make sure it wasn't a read error. */
// errmsg = "reading";
@ -340,6 +336,7 @@ static void parse_config_file(void)
return;
}
s = buffer;
lc++; /* Got a (partial) line. */
/* If a line is too long for our buffer, we consider it an error.
@ -368,7 +365,7 @@ static void parse_config_file(void)
/* Unlike the old code, we ignore leading and trailing
* whitespace for the section name. We also require that
* there are no stray characters after the closing bracket. */
e = strchr(s, ']');
char *e = strchr(s, ']');
if (!e /* Missing right bracket? */
|| e[1] /* Trailing characters? */
|| !*(s = get_trimmed_slice(s+1, e)) /* Missing name? */
@ -399,7 +396,7 @@ static void parse_config_file(void)
* where both key and value could contain inner whitespace. */
/* First get the key (an applet name in our case). */
e = strchr(s, '=');
char *e = strchr(s, '=');
if (e) {
s = get_trimmed_slice(s, e);
}
@ -414,6 +411,9 @@ static void parse_config_file(void)
* up when the busybox configuration is changed. */
applet_no = find_applet_by_name(s);
if (applet_no >= 0) {
int i;
struct suid_config_t *sct;
/* Note: We currently don't check for duplicates!
* The last config line for each applet will be the
* one used since we insert at the head of the list.
@ -453,7 +453,7 @@ static void parse_config_file(void)
goto pe_label;
}
*e++ = ':'; /* get_uidgid doesn't understand user.group */
*e = ':'; /* get_uidgid doesn't understand user.group */
if (get_uidgid(&sct->m_ugid, s, /*allow_numeric:*/ 1) == 0) {
errmsg = "unknown user/group";
goto pe_label;
@ -477,15 +477,11 @@ static void parse_config_file(void)
} /* while (1) */
pe_label:
fclose(f);
bb_error_msg("parse error in %s, line %u: %s", config_file, lc, errmsg);
fclose(f);
/* Release any allocated memory before returning. */
while (sct_head) {
sct = sct_head->m_next;
free(sct_head);
sct_head = sct;
}
llist_free((llist_t*)sct_head, NULL);
}
# else
static inline void parse_config_file(void)
@ -507,7 +503,7 @@ static void check_suid(int applet_no)
# if ENABLE_FEATURE_SUID_CONFIG
if (suid_cfg_readable) {
uid_t uid;
struct BB_suid_config *sct;
struct suid_config_t *sct;
mode_t m;
for (sct = suid_config; sct; sct = sct->m_next) {
@ -545,7 +541,7 @@ static void check_suid(int applet_no)
if (setresuid(-1, uid, uid))
bb_perror_msg_and_die("setresuid");
return;
goto ret;
}
# if !ENABLE_FEATURE_SUID_CONFIG_QUIET
{
@ -553,7 +549,7 @@ static void check_suid(int applet_no)
if (!onetime) {
onetime = 1;
fprintf(stderr, "Using fallback suid method\n");
bb_error_msg("using fallback suid method");
}
}
# endif
@ -568,6 +564,10 @@ static void check_suid(int applet_no)
xsetgid(rgid); /* drop all privileges */
xsetuid(ruid);
}
ret: ;
# if ENABLE_FEATURE_SUID_CONFIG
llist_free((llist_t*)suid_config, NULL);
# endif
}
# else
# define check_suid(x) ((void)0)
@ -784,9 +784,6 @@ int main(int argc UNUSED_PARAM, char **argv)
#endif
{
/* Tweak malloc for reduced memory consumption */
#ifndef PAGE_SIZE
# define PAGE_SIZE (4*1024) /* guess */
#endif
#ifdef M_TRIM_THRESHOLD
/* M_TRIM_THRESHOLD is the maximum amount of freed top-most memory
* to keep before releasing to the OS

View File

@ -62,7 +62,7 @@ void FAST_FUNC llist_unlink(llist_t **head, llist_t *elm)
/* Recursively free all elements in the linked list. If freeit != NULL
* call it on each datum in the list */
void FAST_FUNC llist_free(llist_t *elm, void (*freeit) (void *data))
void FAST_FUNC llist_free(llist_t *elm, void (*freeit)(void *data))
{
while (elm) {
void *data = llist_pop(&elm);