diff --git a/man/systemd.service.xml b/man/systemd.service.xml
index b68d351dff..e89cfe3f0e 100644
--- a/man/systemd.service.xml
+++ b/man/systemd.service.xml
@@ -301,8 +301,9 @@
ExecStop= line set. (Services lacking both ExecStart= and
ExecStop= are not valid.)
- For each of the specified commands, the first argument must be an absolute path to an
- executable. Optionally, this filename may be prefixed with a number of special characters:
+ For each of the specified commands, the first argument must be either an absolute path to an executable
+ or a simple file name without any slashes. Optionally, this filename may be prefixed with a number of special
+ characters:
Special executable prefixes
@@ -1004,11 +1005,9 @@
&, and other elements of shell
syntax are not supported.
- The command to execute must be an absolute path name. It may
- contain spaces, but control characters are not allowed.
+ The command to execute may contain spaces, but control characters are not allowed.
- The command line accepts % specifiers as
- described in
+ The command line accepts % specifiers as described in
systemd.unit5.
Basic environment variable substitution is supported. Use
@@ -1022,10 +1021,20 @@
For this type of expansion, quotes are respected when splitting
into words, and afterwards removed.
+ If the command is not a full (absolute) path, it will be resolved to a full path using a
+ fixed search path determinted at compilation time. Searched directories include
+ /usr/local/bin/, /usr/bin/, /bin/
+ on systems using split /usr/bin/ and /bin/
+ directories, and their sbin/ counterparts on systems using split
+ bin/ and sbin/. It is thus safe to use just the
+ executable name in case of executables located in any of the "standard" directories, and an
+ absolute path must be used in other cases. Using an absolute path is recommended to avoid
+ ambiguity.
+
Example:
Environment="ONE=one" 'TWO=two two'
-ExecStart=/bin/echo $ONE $TWO ${TWO}
+ExecStart=echo $ONE $TWO ${TWO}
This will execute /bin/echo with four
arguments: one, two,
@@ -1035,7 +1044,7 @@ ExecStart=/bin/echo $ONE $TWO ${TWO}
Environment=ONE='one' "TWO='two two' too" THREE=
ExecStart=/bin/echo ${ONE} ${TWO} ${THREE}
ExecStart=/bin/echo $ONE $TWO $THREE
- This results in echo being
+ This results in /bin/echo being
called twice, the first time with arguments
'one',
'two two' too, ,
@@ -1061,27 +1070,27 @@ ExecStart=/bin/echo $ONE $TWO $THREE
Note that shell command lines are not directly supported. If
shell command lines are to be used, they need to be passed
explicitly to a shell implementation of some kind. Example:
- ExecStart=/bin/sh -c 'dmesg | tac'
+ ExecStart=sh -c 'dmesg | tac'
Example:
- ExecStart=/bin/echo one ; /bin/echo "two two"
+ ExecStart=echo one ; echo "two two"
- This will execute /bin/echo two times,
+ This will execute echo two times,
each time with one argument: one and
two two, respectively. Because two commands are
specified, Type=oneshot must be used.
Example:
- ExecStart=/bin/echo / >/dev/null & \; \
-/bin/ls
+ ExecStart=echo / >/dev/null & \; \
+ls
- This will execute /bin/echo
+ This will execute echo
with five arguments: /,
>/dev/null,
&, ;, and
- /bin/ls.
+ ls.
C escapes supported in command lines and environment variables
diff --git a/src/basic/path-util.h b/src/basic/path-util.h
index 73f1769fd9..d5b62e295e 100644
--- a/src/basic/path-util.h
+++ b/src/basic/path-util.h
@@ -30,17 +30,23 @@
#if HAVE_SPLIT_BIN
# define PATH_SBIN_BIN(x) x "sbin:" x "bin"
+# define PATH0_SBIN_BIN(x) x "sbin\0" x "bin"
#else
+# define PATH0_SBIN_BIN(x) x "bin"
# define PATH_SBIN_BIN(x) x "bin"
#endif
#define DEFAULT_PATH_NORMAL PATH_SBIN_BIN("/usr/local/") ":" PATH_SBIN_BIN("/usr/")
+#define DEFAULT_PATH0_NORMAL PATH0_SBIN_BIN("/usr/local/") "\0" PATH0_SBIN_BIN("/usr/")
#define DEFAULT_PATH_SPLIT_USR DEFAULT_PATH_NORMAL ":" PATH_SBIN_BIN("/")
+#define DEFAULT_PATH0_SPLIT_USR DEFAULT_PATH0_NORMAL "\0" PATH0_SBIN_BIN("/")
#if HAVE_SPLIT_USR
# define DEFAULT_PATH DEFAULT_PATH_SPLIT_USR
+# define DEFAULT_PATH_NULSTR DEFAULT_PATH0_SPLIT_USR
#else
# define DEFAULT_PATH DEFAULT_PATH_NORMAL
+# define DEFAULT_PATH_NULSTR DEFAULT_PATH0_NORMAL
#endif
bool is_path(const char *p) _pure_;
diff --git a/src/core/load-fragment.c b/src/core/load-fragment.c
index 887eb1cf49..f9d340df23 100644
--- a/src/core/load-fragment.c
+++ b/src/core/load-fragment.c
@@ -652,23 +652,51 @@ int config_parse_exec(
}
if (!string_is_safe(path)) {
log_syntax(unit, LOG_ERR, filename, line, 0,
- "Executable path contains special characters%s: %s",
- ignore ? ", ignoring" : "", rvalue);
- return ignore ? 0 : -ENOEXEC;
- }
- if (!path_is_absolute(path)) {
- log_syntax(unit, LOG_ERR, filename, line, 0,
- "Executable path is not absolute%s: %s",
- ignore ? ", ignoring" : "", rvalue);
+ "Executable name contains special characters%s: %s",
+ ignore ? ", ignoring" : "", path);
return ignore ? 0 : -ENOEXEC;
}
if (endswith(path, "/")) {
log_syntax(unit, LOG_ERR, filename, line, 0,
"Executable path specifies a directory%s: %s",
- ignore ? ", ignoring" : "", rvalue);
+ ignore ? ", ignoring" : "", path);
return ignore ? 0 : -ENOEXEC;
}
+ if (!path_is_absolute(path)) {
+ const char *prefix;
+ bool found = false;
+
+ if (!filename_is_valid(path)) {
+ log_syntax(unit, LOG_ERR, filename, line, 0,
+ "Neither a valid executable name nor an absolute path%s: %s",
+ ignore ? ", ignoring" : "", path);
+ return ignore ? 0 : -ENOEXEC;
+ }
+
+ /* Resolve a single-component name to a full path */
+ NULSTR_FOREACH(prefix, DEFAULT_PATH_NULSTR) {
+ _cleanup_free_ char *fullpath = NULL;
+
+ fullpath = strjoin(prefix, "/", path);
+ if (!fullpath)
+ return log_oom();
+
+ if (access(fullpath, F_OK) >= 0) {
+ free_and_replace(path, fullpath);
+ found = true;
+ break;
+ }
+ }
+
+ if (!found) {
+ log_syntax(unit, LOG_ERR, filename, line, 0,
+ "Executable \"%s\" not found in path \"%s\"%s",
+ path, DEFAULT_PATH, ignore ? ", ignoring" : "");
+ return ignore ? 0 : -ENOEXEC;
+ }
+ }
+
if (!separate_argv0) {
char *w = NULL;
diff --git a/src/test/test-execute.c b/src/test/test-execute.c
index 81f9b7c344..4c15f1acd5 100644
--- a/src/test/test-execute.c
+++ b/src/test/test-execute.c
@@ -549,6 +549,10 @@ static void test_exec_capabilityboundingset(Manager *m) {
test(m, "exec-capabilityboundingset-invert.service", 0, CLD_EXITED);
}
+static void test_exec_basic(Manager *m) {
+ test(m, "exec-basic.service", 0, CLD_EXITED);
+}
+
static void test_exec_ambientcapabilities(Manager *m) {
int r;
@@ -648,6 +652,7 @@ static int run_tests(UnitFileScope scope, const test_function_t *tests) {
int main(int argc, char *argv[]) {
_cleanup_(rm_rf_physical_and_freep) char *runtime_dir = NULL;
static const test_function_t user_tests[] = {
+ test_exec_basic,
test_exec_ambientcapabilities,
test_exec_bindpaths,
test_exec_capabilityboundingset,
diff --git a/test/meson.build b/test/meson.build
index 809bd44a93..fd4ac11a39 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -45,6 +45,7 @@ test_data_files = '''
sockets.target
son.service
sysinit.target
+ test-execute/exec-basic.service
test-execute/exec-ambientcapabilities-merge-nfsnobody.service
test-execute/exec-ambientcapabilities-merge-nobody.service
test-execute/exec-ambientcapabilities-merge.service
diff --git a/test/test-execute/exec-basic.service b/test/test-execute/exec-basic.service
new file mode 100644
index 0000000000..456f06951a
--- /dev/null
+++ b/test/test-execute/exec-basic.service
@@ -0,0 +1,13 @@
+[Unit]
+Description=Test for basic execution
+
+[Service]
+ExecStart=touch /tmp/a ; /bin/touch /tmp/b ; touch /tmp/c
+ExecStart=test -f /tmp/a
+ExecStart=!test -f /tmp/b
+ExecStart=!!test -f /tmp/c
+ExecStart=+test -f /tmp/c
+ExecStartPost=rm /tmp/a /tmp/b /tmp/c
+
+PrivateTmp=true
+Type=oneshot