On Sun, Apr 30, 2017 at 12:25:04AM +0100, Al Viro wrote: > On Sat, Apr 29, 2017 at 04:17:18PM -0700, Andy Lutomirski wrote: > > On Sat, Apr 29, 2017 at 3:04 PM, Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote: > > > New AT_... flag - AT_NO_JUMPS > > > > > > Semantics: pathname resolution must not involve > > > * traversals of absolute symlinks > > > * traversals of procfs-style symlinks > > > * traversals of mountpoints (including bindings, referrals, etc.) > > > * traversal of .. in the starting point of pathname resolution. > > > > Can you clarify this last one? I assume that ".." will be rejected, > > but what about "a/../.."? How about "b" if b is a symlink to ".."? > > How about "a/b" if a is a directory and b is a symlink to "../.."? > > All of those will be rejected - in each of those cases pathname traversal > leads back into the starting point with .. being the next component to > handle. It sounds more like AT_NO_ESCAPE ... or AT_BELOW, or something. Perhaps some example usages in the changelog? -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
