| Message ID | 1524064686-65246-1-git-send-email-cofyc.jackson@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Wed, Apr 18, 2018 at 11:18:06PM +0800, Yecheng Fu wrote: > `libmount` from util-linux and many softwares in userspace (e.g. > kubelet) did not expect empty string as mount source: > > ``` > $ mount -t tmpfs "" /mnt/tmpfs > $ findmnt /mnt/tmpfs > findmnt: /proc/self/mountinfo: parse error at line 51 > $ cat /proc/self/mountinfo | grep -P '\/mnt\/tmpfs' > 74 25 0:59 / /mnt/tmpfs rw,relatime shared:38 - tmpfs rw > $ cat /proc/self/mounts | grep -P '\/mnt\/tmpfs' > /mnt/tmpfs tmpfs rw,relatime 0 0 > ``` > > `source` field in mounts/mountinfo is empty, which breaks a lot of > mounts/mountinfo parsers when user use empty string as mount source. > > This fixes issues in parsing when user use empty string as mount > source. > > Cc: Karel Zak <kzak@redhat.com> > Signed-off-by: Yecheng Fu <cofyc.jackson@gmail.com> What about show_vfsstat()? Doesn't it need: +++ b/fs/proc_namespace.c @@ -205,7 +205,7 @@ static int show_vfsstat(struct seq_file *m, struct vfsmount *mnt) if (err) goto out; } else { - if (r->mnt_devname) { + if (r->mnt_devname && r->mnt_devname[0] != '\0') { seq_puts(m, "device "); mangle(m, r->mnt_devname); } else
diff --git a/fs/proc_namespace.c b/fs/proc_namespace.c index 3f1190d..0aa16a0 100644 --- a/fs/proc_namespace.c +++ b/fs/proc_namespace.c @@ -104,7 +104,7 @@ static int show_vfsmnt(struct seq_file *m, struct vfsmount *mnt) if (err) goto out; } else { - mangle(m, r->mnt_devname ? r->mnt_devname : "none"); + mangle(m, (r->mnt_devname && r->mnt_devname[0] != '\0') ? r->mnt_devname : "none"); } seq_putc(m, ' '); /* mountpoints outside of chroot jail will give SEQ_SKIP on this */ @@ -174,7 +174,7 @@ static int show_mountinfo(struct seq_file *m, struct vfsmount *mnt) if (err) goto out; } else { - mangle(m, r->mnt_devname ? r->mnt_devname : "none"); + mangle(m, (r->mnt_devname && r->mnt_devname[0] != '\0') ? r->mnt_devname : "none"); } seq_puts(m, sb->s_flags & MS_RDONLY ? " ro" : " rw"); err = show_sb_opts(m, sb);
`libmount` from util-linux and many softwares in userspace (e.g. kubelet) did not expect empty string as mount source: ``` $ mount -t tmpfs "" /mnt/tmpfs $ findmnt /mnt/tmpfs findmnt: /proc/self/mountinfo: parse error at line 51 $ cat /proc/self/mountinfo | grep -P '\/mnt\/tmpfs' 74 25 0:59 / /mnt/tmpfs rw,relatime shared:38 - tmpfs rw $ cat /proc/self/mounts | grep -P '\/mnt\/tmpfs' /mnt/tmpfs tmpfs rw,relatime 0 0 ``` `source` field in mounts/mountinfo is empty, which breaks a lot of mounts/mountinfo parsers when user use empty string as mount source. This fixes issues in parsing when user use empty string as mount source. Cc: Karel Zak <kzak@redhat.com> Signed-off-by: Yecheng Fu <cofyc.jackson@gmail.com> --- fs/proc_namespace.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)