Re: [PATCH] 2.5.50: unused code in link_path_walk()

[Olaf Dietsche <olaf.dietsche#list.linux-kernel@t-online.de>]

Matthew Wilcox <willy@debian.org> writes:

> @@ -700,7 +700,6 @@
>                                  if (this.name[1] != '.')
>                                          break;
>                                  follow_dotdot(&nd->mnt, &nd->dentry);
> -				inode = nd->dentry->d_inode;
>                                  /* fallthrough */
>                          case 1:
>                                  goto return_base;
>
> seems broken to me.  if follow_dotdot() changes nd->dentry (can happen!),
> inode needs to be changed.  look:
>
>         inode = nd->dentry->d_inode;
>         for(;;) {
>                 err = exec_permission_lite(inode);
>                 if (this.name[0] == '.') switch (this.len) {
>                         case 2: 
>                                 if (this.name[1] != '.')
>                                         break;
>                                 follow_dotdot(&nd->mnt, &nd->dentry);
>                                 inode = nd->dentry->d_inode;
>                                 /* fallthrough */
>                         case 1:
>                                 continue;
>                 }
>         }

You looked at the _first_ switch statement. You must go further down
to the _second_ switch. *There*, you don't need this assignment, AFAICS.

> btw, you should cc linux-fsdevel for patches to the VFS.

Thanks for this pointer, I'll spam linux-fsdevel in the future ;-).

Regards, Olaf.