From: Masatake YAMATO <yamato@redhat.com>
Date: Sat, 13 Apr 2024 16:40:14 +0000 (+0900)
Subject: lsns: tolerate lsns_ioctl(fd, NS_GET_{PARENT,USERNS}) failing with ENOSYS
X-Git-Tag: v2.40.1-rc1~33
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=476e88eacd9a6f9d45ca4ef61ab134645e5044c5;p=thirdparty%2Futil-linux.git

lsns: tolerate lsns_ioctl(fd, NS_GET_{PARENT,USERNS}) failing with ENOSYS

With the original code, "lsns/filedesc" test case failed on
"build (qemu-user, s390x)" and "build (qemu-user, riscv64)".

On the platforms, lsns_ioctl(fd, NS_GET_{PARENT,USERNS}) failed
with ENOSYS. The error stoped the iteration for gathering
information from /proc/[0-9]+. As a result, lsns printed
nothing. We don't expect this behavior.

Signed-off-by: Masatake YAMATO <yamato@redhat.com>
(cherry picked from commit f2a8b20d9c63f771d1fddd639ea1ec3fe034dc6d)
---

diff --git a/sys-utils/lsns.c b/sys-utils/lsns.c
index 1f3574f99..4ea01d237 100644
--- a/sys-utils/lsns.c
+++ b/sys-utils/lsns.c
@@ -308,7 +308,11 @@ static int get_ns_ino(int dir, const char *nsname, ino_t *ino, ino_t *pino, ino_
 		return -errno;
 	if (strcmp(nsname, "pid") == 0 || strcmp(nsname, "user") == 0) {
 		if ((pfd = lsns_ioctl(fd, NS_GET_PARENT)) < 0) {
-			if (errno == EPERM)
+			if (errno == EPERM
+			    /* On the test platforms, "build (qemu-user, s390x)" and
+			     * "build (qemu-user, riscv64)", the ioctl reported ENOSYS.
+			     */
+			    || errno == ENOSYS)
 				goto user;
 			close(fd);
 			return -errno;
@@ -323,7 +327,11 @@ static int get_ns_ino(int dir, const char *nsname, ino_t *ino, ino_t *pino, ino_
 	}
  user:
 	if ((ofd = lsns_ioctl(fd, NS_GET_USERNS)) < 0) {
-		if (errno == EPERM)
+		if (errno == EPERM
+		    /* On the test platforms, "build (qemu-user, s390x)" and
+		     * "build (qemu-user, riscv64)", the ioctl reported ENOSYS.
+		     */
+		    || errno == ENOSYS)
 			goto out;
 		close(fd);
 		return -errno;