mirror of
https://github.com/amadvance/snapraid.git
synced 2026-10-26 19:01:57 -04:00
Move user and group resolution before fork for async-signal safety
This commit is contained in:
Andrea Mazzoleni
parent
e946af060e
commit
3c1772d478
1 changed files with 100 additions and 50 deletions
150
os/unix.c
150
os/unix.c
|
|
@ -742,6 +742,74 @@ int os_validate_exec_input(const char* str)
|
|||
return 0;
|
||||
}
|
||||
|
||||
/****************************************************************************/
|
||||
/* user credential management */
|
||||
|
||||
#define GROUPS_MAX 64
|
||||
#define PASSWD_MAX 2048
|
||||
|
||||
struct os_user {
|
||||
int enabled;
|
||||
uid_t uid;
|
||||
gid_t gid;
|
||||
int ngroups;
|
||||
gid_t groups[GROUPS_MAX];
|
||||
};
|
||||
|
||||
#ifdef __APPLE__
|
||||
typedef int os_group_t;
|
||||
#else
|
||||
typedef gid_t os_group_t;
|
||||
#endif
|
||||
|
||||
static int os_user_lookup(const char* run_as_user, struct os_user* user)
|
||||
{
|
||||
memset(user, 0, sizeof(*user));
|
||||
|
||||
if (!run_as_user || run_as_user[0] == 0)
|
||||
return 0;
|
||||
|
||||
struct passwd pw;
|
||||
struct passwd* pw_res = 0;
|
||||
char pw_buf[PASSWD_MAX];
|
||||
int err = getpwnam_r(run_as_user, &pw, pw_buf, sizeof(pw_buf), &pw_res);
|
||||
if (err != 0 || !pw_res) {
|
||||
os_syslog(OS_LVL_INFO, "failed to get user info for %s, errno=%s(%d)", run_as_user, strerror(err ? err : ENOENT), err ? err : ENOENT);
|
||||
return -1;
|
||||
}
|
||||
|
||||
user->enabled = 1;
|
||||
user->uid = pw.pw_uid;
|
||||
user->gid = pw.pw_gid;
|
||||
|
||||
os_group_t groups_buf[GROUPS_MAX];
|
||||
int ngroups = sizeof(groups_buf) / sizeof(groups_buf[0]);
|
||||
|
||||
if (getgrouplist(pw.pw_name, (os_group_t)pw.pw_gid, groups_buf, &ngroups) < 0) {
|
||||
os_syslog(OS_LVL_INFO, "failed to get group list for %s, exceeds maximum of %d groups", run_as_user, GROUPS_MAX);
|
||||
return -1;
|
||||
}
|
||||
|
||||
user->ngroups = ngroups;
|
||||
for (int i = 0; i < ngroups; ++i) {
|
||||
user->groups[i] = (gid_t)groups_buf[i];
|
||||
}
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static void os_user_drop_privileges(const struct os_user* user)
|
||||
{
|
||||
if (user->enabled) {
|
||||
if (setgroups(user->ngroups, user->groups) != 0)
|
||||
_exit(126);
|
||||
if (setgid(user->gid) != 0)
|
||||
_exit(126);
|
||||
if (setuid(user->uid) != 0)
|
||||
_exit(126);
|
||||
}
|
||||
}
|
||||
|
||||
/**
|
||||
* Executes a script directly via its file descriptor.
|
||||
*/
|
||||
|
|
@ -752,6 +820,7 @@ int os_script(char** argv, char** envp, const char* run_as_user)
|
|||
int ret;
|
||||
int status;
|
||||
int64_t start, stop;
|
||||
struct os_user user;
|
||||
|
||||
int fd = verify_executable(argv[0], resolved_path, 1);
|
||||
if (fd < 0) {
|
||||
|
|
@ -763,6 +832,11 @@ int os_script(char** argv, char** envp, const char* run_as_user)
|
|||
return -1;
|
||||
}
|
||||
|
||||
if (os_user_lookup(run_as_user, &user) != 0) {
|
||||
close(fd);
|
||||
return -1;
|
||||
}
|
||||
|
||||
start = os_tick_sec();
|
||||
|
||||
#if defined(__linux__) && defined(PR_SET_PDEATHSIG)
|
||||
|
|
@ -788,23 +862,7 @@ int os_script(char** argv, char** envp, const char* run_as_user)
|
|||
setpgid(0, 0);
|
||||
|
||||
/* drop privileges first (if configured) */
|
||||
if (run_as_user && run_as_user[0] != 0) {
|
||||
errno = 0;
|
||||
struct passwd* pw = getpwnam(run_as_user);
|
||||
if (!pw) {
|
||||
/* if errno is 0, user simply wasn't found. Otherwise, it's a real error */
|
||||
if (errno == 0)
|
||||
_exit(127);
|
||||
else
|
||||
_exit(126);
|
||||
}
|
||||
if (initgroups(pw->pw_name, pw->pw_gid) != 0)
|
||||
_exit(126);
|
||||
if (setgid(pw->pw_gid) != 0)
|
||||
_exit(126);
|
||||
if (setuid(pw->pw_uid) != 0)
|
||||
_exit(126);
|
||||
}
|
||||
os_user_drop_privileges(&user);
|
||||
|
||||
#if defined(__linux__) && defined(PR_SET_PDEATHSIG)
|
||||
/* Send SIGKILL to child if parent daemon dies unexpectedly */
|
||||
|
|
@ -938,6 +996,7 @@ int os_command(const char* command, const char* run_as_user, const char* stdin_t
|
|||
int status;
|
||||
int pipe_fds[2] = { -1, -1 };
|
||||
int64_t start, stop;
|
||||
struct os_user user;
|
||||
|
||||
/* create pipe only if we have text to send */
|
||||
if (stdin_text != NULL) {
|
||||
|
|
@ -947,6 +1006,14 @@ int os_command(const char* command, const char* run_as_user, const char* stdin_t
|
|||
}
|
||||
}
|
||||
|
||||
if (os_user_lookup(run_as_user, &user) != 0) {
|
||||
if (pipe_fds[0] != -1) {
|
||||
close(pipe_fds[0]);
|
||||
close(pipe_fds[1]);
|
||||
}
|
||||
return -1;
|
||||
}
|
||||
|
||||
start = os_tick_sec();
|
||||
|
||||
#if defined(__linux__) && defined(PR_SET_PDEATHSIG)
|
||||
|
|
@ -978,23 +1045,7 @@ int os_command(const char* command, const char* run_as_user, const char* stdin_t
|
|||
close(pipe_fds[1]); /* Close unused write end */
|
||||
|
||||
/* drop privileges first (if configured) */
|
||||
if (run_as_user && run_as_user[0] != 0) {
|
||||
errno = 0;
|
||||
struct passwd* pw = getpwnam(run_as_user);
|
||||
if (!pw) {
|
||||
/* if errno is 0, user simply wasn't found. Otherwise, it's a real error */
|
||||
if (errno == 0)
|
||||
_exit(127);
|
||||
else
|
||||
_exit(126);
|
||||
}
|
||||
if (initgroups(pw->pw_name, pw->pw_gid) != 0)
|
||||
_exit(126);
|
||||
if (setgid(pw->pw_gid) != 0)
|
||||
_exit(126);
|
||||
if (setuid(pw->pw_uid) != 0)
|
||||
_exit(126);
|
||||
}
|
||||
os_user_drop_privileges(&user);
|
||||
|
||||
#if defined(__linux__) && defined(PR_SET_PDEATHSIG)
|
||||
/* Send SIGKILL to child if parent daemon dies unexpectedly */
|
||||
|
|
@ -1160,6 +1211,7 @@ pid_t os_spawn(char** argv, int* stdout_read_fd, int* stderr_read_fd, const char
|
|||
int has_out = (stdout_read_fd != NULL);
|
||||
int has_err = (stderr_read_fd != NULL);
|
||||
pid_t pid;
|
||||
struct os_user user;
|
||||
|
||||
int fd = verify_executable(argv[0], resolved_path, 0);
|
||||
if (fd < 0) {
|
||||
|
|
@ -1186,6 +1238,19 @@ pid_t os_spawn(char** argv, int* stdout_read_fd, int* stderr_read_fd, const char
|
|||
}
|
||||
}
|
||||
|
||||
if (os_user_lookup(run_as_user, &user) != 0) {
|
||||
if (has_out) {
|
||||
close(out_pipe[0]);
|
||||
close(out_pipe[1]);
|
||||
}
|
||||
if (has_err) {
|
||||
close(err_pipe[0]);
|
||||
close(err_pipe[1]);
|
||||
}
|
||||
close(fd);
|
||||
return -1;
|
||||
}
|
||||
|
||||
#if defined(__linux__) && defined(PR_SET_PDEATHSIG)
|
||||
pid_t ppid = getpid();
|
||||
#endif
|
||||
|
|
@ -1211,22 +1276,7 @@ pid_t os_spawn(char** argv, int* stdout_read_fd, int* stderr_read_fd, const char
|
|||
setpgid(0, 0);
|
||||
|
||||
/* drop privileges first (if configured) */
|
||||
if (run_as_user && run_as_user[0] != 0) {
|
||||
errno = 0;
|
||||
struct passwd* pw = getpwnam(run_as_user);
|
||||
if (!pw) {
|
||||
if (errno == 0)
|
||||
_exit(127);
|
||||
else
|
||||
_exit(126);
|
||||
}
|
||||
if (initgroups(pw->pw_name, pw->pw_gid) != 0)
|
||||
_exit(126);
|
||||
if (setgid(pw->pw_gid) != 0)
|
||||
_exit(126);
|
||||
if (setuid(pw->pw_uid) != 0)
|
||||
_exit(126);
|
||||
}
|
||||
os_user_drop_privileges(&user);
|
||||
|
||||
#if defined(__linux__) && defined(PR_SET_PDEATHSIG)
|
||||
/* Send SIGKILL to child if parent daemon dies unexpectedly */
|
||||
|
|
|
|||
Loading…
Add table
Add a link
Reference in a new issue