From: Paolo Bonzini <pbonz...@redhat.com>
There is a minor time of check/time of use race between statfs and chroot.
It can be fixed easily by stat-ing the root after it has been changed.
Signed-off-by: Paolo Bonzini <pbonz...@redhat.com>
Reviewed-by: Greg Kurz <gk...@linux.vnet.ibm.com>
Signed-off-by: Greg Kurz <gk...@linux.vnet.ibm.com>
---
fsdev/virtfs-proxy-helper.c | 20 ++++++++++----------
1 file changed, 10 insertions(+), 10 deletions(-)
diff --git a/fsdev/virtfs-proxy-helper.c b/fsdev/virtfs-proxy-helper.c
index 9097d15c989c..ad1da0d6f530 100644
--- a/fsdev/virtfs-proxy-helper.c
+++ b/fsdev/virtfs-proxy-helper.c
@@ -1128,10 +1128,19 @@ int main(int argc, char **argv)
}
}
+ if (chdir("/") < 0) {
+ do_perror("chdir");
+ goto error;
+ }
+ if (chroot(rpath) < 0) {
+ do_perror("chroot");
+ goto error;
+ }
+
get_version = false;
#ifdef FS_IOC_GETVERSION
/* check whether underlying FS support IOC_GETVERSION */
- retval = statfs(rpath, &st_fs);
+ retval = statfs("/", &st_fs);
if (!retval) {
switch (st_fs.f_type) {
case EXT2_SUPER_MAGIC:
@@ -1144,16 +1153,7 @@ int main(int argc, char **argv)
}
#endif
- if (chdir("/") < 0) {
- do_perror("chdir");
- goto error;
- }
- if (chroot(rpath) < 0) {
- do_perror("chroot");
- goto error;
- }
umask(0);
-
if (init_capabilities() < 0) {
goto error;
}
--
2.4.3
