shaba/systemd
1
0
Fork 0
mirror of https://github.com/systemd/systemd.git synced 2025-03-31 14:50:15 +03:00
Code

sd-dameon: also sent ucred when our UID differs from EUID

Browse Source 
Let's be explicit, and always send the messages from our UID and never
our EUID. Previously this behaviour was conditionalized only on whether
the PID was specified, which made this non-obvious.
This commit is contained in:
Lennart Poettering 2018-01-05 13:24:58 +01:00
parent 15e23e8cdf
commit 9e1d021ee3
1 changed files with 19 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

29
src/libsystemd/sd-daemon/sd-daemon.c
View File

@ -455,7 +455,13 @@ _public_ int sd_is_mq(int fd, const char *path) {
return 1;
}
_public_ int sd_pid_notify_with_fds(pid_t pid, int unset_environment, const char *state, const int *fds, unsigned n_fds) {
_public_ int sd_pid_notify_with_fds(
pid_t pid,
int unset_environment,
const char *state,
const int *fds,
unsigned n_fds) {
union sockaddr_union sockaddr = {
.sa.sa_family = AF_UNIX,
};
@ -470,7 +476,7 @@ _public_ int sd_pid_notify_with_fds(pid_t pid, int unset_environment, const char
_cleanup_close_ int fd = -1;
struct cmsghdr *cmsg = NULL;
const char *e;
bool have_pid;
bool send_ucred;
int r;
if (!state) {
@ -504,7 +510,7 @@ _public_ int sd_pid_notify_with_fds(pid_t pid, int unset_environment, const char
goto finish;
}
fd_inc_sndbuf(fd, SNDBUF_SIZE);
(void) fd_inc_sndbuf(fd, SNDBUF_SIZE);
iovec.iov_len = strlen(state);
@ -514,13 +520,16 @@ _public_ int sd_pid_notify_with_fds(pid_t pid, int unset_environment, const char
msghdr.msg_namelen = SOCKADDR_UN_LEN(sockaddr.un);
have_pid = pid != 0 && pid != getpid_cached();
send_ucred =
(pid != 0 && pid != getpid_cached()) ||
getuid() != geteuid() ||
getgid() != getegid();
if (n_fds > 0 || have_pid) {
if (n_fds > 0 || send_ucred) {
/* CMSG_SPACE(0) may return value different than zero, which results in miscalculated controllen. */
msghdr.msg_controllen =
(n_fds > 0 ? CMSG_SPACE(sizeof(int) * n_fds) : 0) +
(have_pid ? CMSG_SPACE(sizeof(struct ucred)) : 0);
(send_ucred ? CMSG_SPACE(sizeof(struct ucred)) : 0);
msghdr.msg_control = alloca0(msghdr.msg_controllen);
@ -532,11 +541,11 @@ _public_ int sd_pid_notify_with_fds(pid_t pid, int unset_environment, const char
memcpy(CMSG_DATA(cmsg), fds, sizeof(int) * n_fds);
if (have_pid)
if (send_ucred)
assert_se(cmsg = CMSG_NXTHDR(&msghdr, cmsg));
}
if (have_pid) {
if (send_ucred) {
struct ucred *ucred;
cmsg->cmsg_level = SOL_SOCKET;
@ -544,7 +553,7 @@ _public_ int sd_pid_notify_with_fds(pid_t pid, int unset_environment, const char
cmsg->cmsg_len = CMSG_LEN(sizeof(struct ucred));
ucred = (struct ucred*) CMSG_DATA(cmsg);
ucred->pid = pid;
ucred->pid = pid != 0 ? pid : getpid_cached();
ucred->uid = getuid();
ucred->gid = getgid();
}
@ -557,7 +566,7 @@ _public_ int sd_pid_notify_with_fds(pid_t pid, int unset_environment, const char
}
/* If that failed, try with our own ucred instead */
if (have_pid) {
if (send_ucred) {
msghdr.msg_controllen -= CMSG_SPACE(sizeof(struct ucred));
if (msghdr.msg_controllen == 0)
msghdr.msg_control = NULL;