+/* SPDX-License-Identifier: LGPL-2.1+ */
/***
This file is part of systemd.
#include <sys/wait.h>
#include <syslog.h>
#include <unistd.h>
-#ifdef HAVE_VALGRIND_VALGRIND_H
+#if HAVE_VALGRIND_VALGRIND_H
#include <valgrind/valgrind.h>
#endif
/* Third step, completely replace the argv[] array the kernel maintains for us. This requires privileges, but
* has the advantage that the argv[] array is exactly what we want it to be, and not filled up with zeros at
* the end. This is the best option for changing /proc/self/cmdline. */
- if (mm_size < l+1) {
+
+ /* Let's not bother with this if we don't have euid == 0. Strictly speaking we should check for the
+ * CAP_SYS_RESOURCE capability which is independent of the euid. In our own code the capability generally is
+ * present only for euid == 0, hence let's use this as quick bypass check, to avoid calling mmap() if
+ * PR_SET_MM_ARG_{START,END} fails with EPERM later on anyway. After all geteuid() is dead cheap to call, but
+ * mmap() is not. */
+ if (geteuid() != 0)
+ log_debug("Skipping PR_SET_MM, as we don't have privileges.");
+ else if (mm_size < l+1) {
size_t nn_size;
char *nn;
- /* Let's not bother with this if we don't have euid == 0. Strictly speaking if people do weird stuff
- * with capabilities this could work even for euid != 0, but our own code generally doesn't do that,
- * hence let's use this as quick bypass check, to avoid calling mmap() if PR_SET_MM_ARG_START fails
- * with EPERM later on anyway. After all geteuid() is dead cheap to call, but mmap() is not. */
- if (geteuid() != 0) {
- log_debug("Skipping PR_SET_MM_ARG_START, as we don't have privileges.");
- goto use_saved_argv;
- }
-
nn_size = PAGE_ALIGN(l+1);
nn = mmap(NULL, nn_size, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0);
if (nn == MAP_FAILED) {
mm = nn;
mm_size = nn_size;
- } else
+ } else {
strncpy(mm, name, mm_size);
+ /* Update the end pointer, continuing regardless of any failure. */
+ if (prctl(PR_SET_MM, PR_SET_MM_ARG_END, (unsigned long) mm + l + 1, 0, 0) < 0)
+ log_debug_errno(errno, "PR_SET_MM_ARG_END failed, proceeding without: %m");
+ }
+
use_saved_argv:
/* Fourth step: in all cases we'll also update the original argv[], so that our own code gets it right too if
* it still looks here */
bool eof;
FILE *f;
- if (pid == 0 || pid == 1 || pid == getpid_cached()) /* pid 1, and we ourselves certainly aren't a kernel thread */
+ if (IN_SET(pid, 0, 1) || pid == getpid_cached()) /* pid 1, and we ourselves certainly aren't a kernel thread */
return 0;
assert(pid > 1);
log_debug("%s succeeded.", name);
return status.si_status;
- } else if (status.si_code == CLD_KILLED ||
- status.si_code == CLD_DUMPED) {
+ } else if (IN_SET(status.si_code, CLD_KILLED, CLD_DUMPED)) {
log_warning("%s terminated by signal %s.", name, signal_to_string(status.si_status));
return -EPROTO;
return true;
r = get_process_state(pid);
- if (r == -ESRCH || r == 'Z')
+ if (IN_SET(r, -ESRCH, 'Z'))
return false;
return true;
return architecture_to_string(architecture);
}
+int safe_personality(unsigned long p) {
+ int ret;
+
+ /* So here's the deal, personality() is weirdly defined by glibc. In some cases it returns a failure via errno,
+ * and in others as negative return value containing an errno-like value. Let's work around this: this is a
+ * wrapper that uses errno if it is set, and uses the return value otherwise. And then it sets both errno and
+ * the return value indicating the same issue, so that we are definitely on the safe side.
+ *
+ * See https://github.com/systemd/systemd/issues/6737 */
+
+ errno = 0;
+ ret = personality(p);
+ if (ret < 0) {
+ if (errno != 0)
+ return -errno;
+
+ errno = -ret;
+ }
+
+ return ret;
+}
+
+int opinionated_personality(unsigned long *ret) {
+ int current;
+
+ /* Returns the current personality, or PERSONALITY_INVALID if we can't determine it. This function is a bit
+ * opinionated though, and ignores all the finer-grained bits and exotic personalities, only distinguishing the
+ * two most relevant personalities: PER_LINUX and PER_LINUX32. */
+
+ current = safe_personality(PERSONALITY_INVALID);
+ if (current < 0)
+ return current;
+
+ if (((unsigned long) current & 0xffff) == PER_LINUX32)
+ *ret = PER_LINUX32;
+ else
+ *ret = PER_LINUX;
+
+ return 0;
+}
+
void valgrind_summary_hack(void) {
-#ifdef HAVE_VALGRIND_VALGRIND_H
+#if HAVE_VALGRIND_VALGRIND_H
if (getpid_cached() == 1 && RUNNING_ON_VALGRIND) {
pid_t pid;
pid = raw_clone(SIGCHLD);
* objects were used across fork()s. With this caching the old behaviour is somewhat restored.
*
* https://bugzilla.redhat.com/show_bug.cgi?id=1443976
- * https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=1d2bc2eae969543b89850e35e532f3144122d80a
+ * https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=c579f48edba88380635ab98cb612030e3ed8691e
*/
current_value = __sync_val_compare_and_swap(&cached_pid, CACHED_PID_UNSET, CACHED_PID_BUSY);