By calling mount(2) with MS_REMOUNT | MS_BIND on a non-bind readonly mountpoint, it is possible to have a readonly mount without MNT_READONLY in its mnt_flags. Currently, /proc/<pid>/mountinfo will report such a mount as r/w in the 4th column, even though for all intents and purposes it is still readonly.
This patch makes show_mountinfo use __mnt_is_readonly to check if a mount is readonly, which checks both for MNT_READONLY in mnt_flags and for MS_RDONLY in mnt_sb->s_flags. Signed-off-by: Shea Levy <[email protected]> --- fs/proc_namespace.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/proc_namespace.c b/fs/proc_namespace.c index 5fe34c3..cf8963c 100644 --- a/fs/proc_namespace.c +++ b/fs/proc_namespace.c @@ -143,7 +143,7 @@ static int show_mountinfo(struct seq_file *m, struct vfsmount *mnt) if (err) goto out; - seq_puts(m, mnt->mnt_flags & MNT_READONLY ? " ro" : " rw"); + seq_puts(m, __mnt_is_readonly(mnt) ? " ro" : " rw"); show_mnt_opts(m, mnt); /* Tagged fields ("foo:X" or "bar") */ -- 1.8.1.3 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
