Re: [PATCH v15 5/9] namei: LOOKUP_IN_ROOT: chroot-like scoped resolution
From: Al Viro <viro@zeniv.linux.org.uk>
Date: 2019-11-13 02:03:45
Also in:
linux-alpha, linux-api, linux-arch, linux-arm-kernel, linux-fsdevel, linux-kselftest, linux-mips, linux-s390, linux-sh, lkml, sparclinux
On Tue, Nov 05, 2019 at 08:05:49PM +1100, Aleksa Sarai wrote:
quoted hunk ↗ jump to hunk
@@ -2277,12 +2277,20 @@ static const char *path_init(struct nameidata *nd, unsigned flags) nd->m_seq = read_seqbegin(&mount_lock); - /* Figure out the starting path and root (if needed). */ - if (*s == '/') { + /* Absolute pathname -- fetch the root. */ + if (flags & LOOKUP_IN_ROOT) { + /* With LOOKUP_IN_ROOT, act as a relative path. */ + while (*s == '/') + s++;
Er... Why bother skipping slashes? I mean, not only link_path_walk()
will skip them just fine, you are actually risking breakage in this:
if (*s && unlikely(!d_can_lookup(dentry))) {
fdput(f);
return ERR_PTR(-ENOTDIR);
}
which is downstream from there with you patch, AFAICS.