From: Karel Zak <kzak@redhat.com>
Date: Tue, 10 Jan 2023 11:40:47 +0000 (+0100)
Subject: libmount: use MNT_ERR_APPLYFLAGS for failed mount_setattr()
X-Git-Tag: v2.39-rc1~171
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=987d844cdbc0f91ca81de3c1e5d0628a60eb458f;p=thirdparty%2Futil-linux.git

libmount: use MNT_ERR_APPLYFLAGS for failed mount_setattr()

The classic mount(2) based version uses MNT_ERR_APPLYFLAGS when not
able to set flags and errno is EINVAL. This is expected by
mnt_context_get_mount_excode() where libmount generates error messages
for mount(8).

Expected is:

 # mount --make-private /mnt/test
 mount: /mnt/test: not mount point or bad option.

rather than generic error:

 mount: /mnt/test: wrong fs type, bad option, bad superblock on none ...

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/libmount/src/hook_mount.c b/libmount/src/hook_mount.c
index 6f3dfca0bc..1c5fcc8e79 100644
--- a/libmount/src/hook_mount.c
+++ b/libmount/src/hook_mount.c
@@ -348,6 +348,9 @@ static int hook_set_vfsflags(struct libmnt_context *cxt,
 
 	rc = mount_setattr(api->fd_tree, "", callflags, &attr, sizeof(attr));
 	set_syscall_status(cxt, "move_setattr", rc == 0);
+
+	if (rc && errno == EINVAL)
+		return -MNT_ERR_APPLYFLAGS;
 done:
 	return rc == 0 ? 0 : -errno;
 }
@@ -405,6 +408,9 @@ static int hook_set_propagation(struct libmnt_context *cxt,
 
 		rc = mount_setattr(api->fd_tree, "", flgs, &attr, sizeof(attr));
 		set_syscall_status(cxt, "move_setattr", rc == 0);
+
+		if (rc && errno == EINVAL)
+			return -MNT_ERR_APPLYFLAGS;
 		if (rc != 0)
 			break;
 	}