From: Christian Goeschel Ndjomouo <cgoesc2@wgu.edu>
Date: Tue, 25 Nov 2025 04:54:39 +0000 (-0500)
Subject: kill: use ul_get_valid_pidfd_or_err() to validate user provided pidfd inodes
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=15225d77b822d05da2561ee874d5927f9d4eeb0b;p=thirdparty%2Futil-linux.git

kill: use ul_get_valid_pidfd_or_err() to validate user provided pidfd inodes

Signed-off-by: Christian Goeschel Ndjomouo <cgoesc2@wgu.edu>
---

diff --git a/misc-utils/kill.c b/misc-utils/kill.c
index 245c3b6b7..ff0dcae52 100644
--- a/misc-utils/kill.c
+++ b/misc-utils/kill.c
@@ -534,8 +534,7 @@ static int kill_with_timeout(const struct kill_control *ctl)
 	info.si_value.sival_int =
 	    ctl->use_sigval != 0 ? ctl->use_sigval : ctl->numsig;
 
-	if ((pfd = pidfd_open(ctl->pid, 0)) < 0)
-		err(EXIT_FAILURE, _("pidfd_open() failed: %d"), ctl->pid);
+	pfd = ul_get_valid_pidfd_or_err(ctl->pid, ctl->pidfd_ino);
 	p.fd = pfd;
 	p.events = POLLIN;
 
@@ -564,22 +563,6 @@ static int kill_with_timeout(const struct kill_control *ctl)
 }
 #endif
 
-#ifdef USE_KILL_WITH_PIDFDINO
-static int validate_pfd_ino(int pfd, ino_t pfd_ino)
-{
-	int rc;
-	struct stat f;
-
-	rc = fstat(pfd, &f);
-	if (rc != 0)
-		return -EINVAL;
-
-	if (f.st_ino != pfd_ino)
-		return -EINVAL;
-	return 0;
-}
-#endif
-
 static int kill_verbose(const struct kill_control *ctl)
 {
 	int rc = 0;
@@ -603,15 +586,7 @@ static int kill_verbose(const struct kill_control *ctl)
 #ifdef USE_KILL_WITH_PIDFDINO
 		if ((ctl->pidfd_ino > 0)) {
 			int pfd;
-			pfd = pidfd_open(ctl->pid, 0);
-			if (pfd < 0)
-				err(EXIT_FAILURE, _("pidfd_open() failed: %d"), ctl->pid);
-
-			rc = validate_pfd_ino(pfd, ctl->pidfd_ino);
-			if (rc < 0)
-				errx(EXIT_FAILURE, _("pidfd inode %"PRIu64" not found for pid %d: %s"),
-								ctl->pidfd_ino, ctl->pid, strerror(-rc));
-
+			pfd = ul_get_valid_pidfd_or_err(ctl->pid, ctl->pidfd_ino);
 			rc = pidfd_send_signal(pfd, ctl->numsig, 0, 0);
 			if (rc < 0)
 				err(EXIT_FAILURE, _("pidfd_send_signal() failed"));