summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLennart Poettering <lennart@poettering.net>2012-01-14 03:37:32 +0100
committerLennart Poettering <lennart@poettering.net>2012-01-14 03:37:32 +0100
commitfee80f695687ab3bfb0590e73d6d97a8a19787cd (patch)
tree89de74a7529e8432440b6402d9cd419c71cded35
parente6acda19b26e5a8e490b48b15e2ba33d9103b3bd (diff)
journal: drop privileges when storing coredump
-rw-r--r--src/journal/coredump.c57
1 files changed, 41 insertions, 16 deletions
diff --git a/src/journal/coredump.c b/src/journal/coredump.c
index bbec550784..6b8809972d 100644
--- a/src/journal/coredump.c
+++ b/src/journal/coredump.c
@@ -45,6 +45,8 @@ int main(int argc, char* argv[]) {
char *p = NULL;
ssize_t n;
pid_t pid;
+ uid_t uid;
+ gid_t gid;
struct iovec iovec[14];
char *core_pid = NULL, *core_uid = NULL, *core_gid = NULL, *core_signal = NULL,
*core_timestamp = NULL, *core_comm = NULL, *core_exe = NULL, *core_unit = NULL,
@@ -63,31 +65,21 @@ int main(int argc, char* argv[]) {
r = parse_pid(argv[ARG_PID], &pid);
if (r < 0) {
log_error("Failed to parse PID.");
- r = -EINVAL;
goto finish;
}
- p = malloc(9 + COREDUMP_MAX);
- if (!p) {
- log_error("Out of memory");
- r = -ENOMEM;
+ r = parse_uid(argv[ARG_UID], &uid);
+ if (r < 0) {
+ log_error("Failed to parse UID.");
goto finish;
}
- memcpy(p, "COREDUMP=", 9);
-
- n = loop_read(STDIN_FILENO, p + 9, COREDUMP_MAX, false);
- if (n < 0) {
- log_error("Failed to read core dump data: %s", strerror(-n));
- r = (int) n;
+ r = parse_gid(argv[ARG_GID], &gid);
+ if (r < 0) {
+ log_error("Failed to parse GID.");
goto finish;
}
- zero(iovec);
- iovec[j].iov_base = p;
- iovec[j].iov_len = 9 + n;
- j++;
-
core_pid = strappend("COREDUMP_PID=", argv[ARG_PID]);
if (core_pid)
IOVEC_SET_STRING(iovec[j++], core_pid);
@@ -151,6 +143,39 @@ int main(int argc, char* argv[]) {
if (core_message)
IOVEC_SET_STRING(iovec[j++], core_message);
+ /* Now, let's drop privileges to become the user who owns the
+ * segfaulted process and allocate the coredump memory under
+ * his uid. This also ensures that the credentials journald
+ * will see are the ones of the coredumping user, thus making
+ * sure the user himself gets access to the core dump. */
+
+ if (setresgid(gid, gid, gid) < 0 ||
+ setresuid(uid, uid, uid) < 0) {
+ log_error("Failed to drop privileges: %m");
+ r = -errno;
+ goto finish;
+ }
+
+ p = malloc(9 + COREDUMP_MAX);
+ if (!p) {
+ log_error("Out of memory");
+ r = -ENOMEM;
+ goto finish;
+ }
+
+ memcpy(p, "COREDUMP=", 9);
+
+ n = loop_read(STDIN_FILENO, p + 9, COREDUMP_MAX, false);
+ if (n < 0) {
+ log_error("Failed to read core dump data: %s", strerror(-n));
+ r = (int) n;
+ goto finish;
+ }
+
+ iovec[j].iov_base = p;
+ iovec[j].iov_len = 9 + n;
+ j++;
+
r = sd_journal_sendv(iovec, j);
if (r < 0)
log_error("Failed to send coredump: %s", strerror(-r));