ahp/busybox
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

hush: fix "type ./cat" and "command -v ./cat" to not scan PATH

Browse source 
function                                             old     new   delta
find_executable_in_PATH                                -      67     +67
if_command_vV_print_and_exit                         114     116      +2
.rodata                                           105712  105710      -2
builtin_type                                         137     128      -9
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 1/2 up/down: 69/-11)             Total: 58 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2024-10-07 22:00:16 +02:00
parent baa49bdc1b
commit 8c4bccb83e
1 changed files with 33 additions and 13 deletions
Download patch file Download diff file Expand all files Collapse all files

46
shell/hush.c
View file

@ -8201,27 +8201,29 @@ static int setup_redirects(struct command *prog, struct squirrel **sqp)
return 0; return 0;
} }
/* Find a file in PATH, not necessarily executable */ /* Find a file in PATH, not necessarily executable
* Name is known to not contain '/'.
*/
//TODO: shares code with find_executable() in libbb, factor out? //TODO: shares code with find_executable() in libbb, factor out?
static char *find_in_path(const char *arg) static char *find_in_PATH(const char *name)
{ {
char *ret = NULL; char *ret;
const char *PATH = get_local_var_value("PATH"); const char *PATH = get_local_var_value("PATH");
if (!PATH) if (!PATH)
return NULL; return NULL;
ret = NULL;
while (1) { while (1) {
const char *end = strchrnul(PATH, ':'); const char *end = strchrnul(PATH, ':');
int sz = end - PATH; /* must be int! */ int sz = end - PATH; /* must be int! */
free(ret); free(ret);
if (sz != 0) { if (sz != 0) {
ret = xasprintf("%.*s/%s", sz, PATH, arg); ret = xasprintf("%.*s/%s", sz, PATH, name);
} else { } else {
/* We have xxx::yyyy in $PATH, /* We have xxx::yyyy in $PATH,
* it means "use current dir" */ * it means "use current dir" */
ret = xstrdup(arg); ret = xstrdup(name);
} }
if (access(ret, F_OK) == 0) if (access(ret, F_OK) == 0)
break; break;
@ -8236,6 +8238,24 @@ static char *find_in_path(const char *arg)
return ret; return ret;
} }
#if ENABLE_HUSH_TYPE || ENABLE_HUSH_COMMAND
static char *find_executable_in_PATH(const char *name)
{
char *PATH;
if (strchr(name, '/')) {
/* Name with '/' is tested verbatim, with no PATH traversal:
* "cd /bin; type ./cat" should print "./cat is ./cat",
* NOT "./cat is /bin/./cat"
*/
if (file_is_executable(name))
return xstrdup(name);
return NULL;
}
PATH = (char*)get_local_var_value("PATH");
return find_executable(name, &PATH); /* path == NULL is ok */
}
#endif
static const struct built_in_command *find_builtin_helper(const char *name, static const struct built_in_command *find_builtin_helper(const char *name,
const struct built_in_command *x, const struct built_in_command *x,
const struct built_in_command *end) const struct built_in_command *end)
@ -8645,10 +8665,11 @@ static void if_command_vV_print_and_exit(char opt_vV, char *cmd, const char *exp
to_free = NULL; to_free = NULL;
if (!explanation) { if (!explanation) {
char *path = (char*)get_local_var_value("PATH"); explanation = to_free = find_executable_in_PATH(cmd);
explanation = to_free = find_executable(cmd, &path); /* path == NULL is ok */ if (!explanation) {
if (!explanation) bb_error_msg("%s: %s: not found", "command", cmd);
_exit(1); /* PROG was not found */ _exit(1); /* PROG was not found */
}
if (opt_vV != 'V') if (opt_vV != 'V')
cmd = to_free; /* -v PROG prints "/path/to/PROG" */ cmd = to_free; /* -v PROG prints "/path/to/PROG" */
} }
@ -11075,12 +11096,11 @@ static int FAST_FUNC builtin_type(char **argv)
else if (find_builtin(*argv)) else if (find_builtin(*argv))
type = "a shell builtin"; type = "a shell builtin";
else { else {
char *pathvar = (char*)get_local_var_value("PATH"); path = find_executable_in_PATH(*argv);
path = find_executable(*argv, &pathvar);
if (path) if (path)
type = path; type = path;
else { else {
bb_error_msg("type: %s: not found", *argv); bb_error_msg("%s: %s: not found", "type", *argv);
ret = EXIT_FAILURE; ret = EXIT_FAILURE;
continue; continue;
} }
@ -11710,7 +11730,7 @@ static int FAST_FUNC builtin_source(char **argv)
} }
arg_path = NULL; arg_path = NULL;
if (!strchr(filename, '/')) { if (!strchr(filename, '/')) {
arg_path = find_in_path(filename); arg_path = find_in_PATH(filename);
if (arg_path) if (arg_path)
filename = arg_path; filename = arg_path;
else if (!ENABLE_HUSH_BASH_SOURCE_CURDIR) { else if (!ENABLE_HUSH_BASH_SOURCE_CURDIR) {