2.1.132

 fs

diff -u --recursive --new-file v2.1.131/linux/fs/ChangeLog linux/fs/ChangeLog
--- v2.1.131/linux/fs/ChangeLog   Tue Oct 25 09:10:14 1994
+++ linux/fs/ChangeLog   Fri Dec 18 07:09:35 1998
@@ -8,3 +8,169 @@
    * fcntl.c (sys_fcntl): Add more of a security check to the
       F_SETOWN fcntl().
 
+[Tons of changes missed, indeed. This list is worth restarting since
+at least some fixes WILL break third-party filesystems. Sorry, but
+there was no other way to fix rmdir/rename deadlock, for one.]
+
+Wed Dec  2 (Linus, fill the rest, please)
+
+   * namei.c (do_rmdir) and rmdir method in filesystems:
+      Locking of directory we remove was taken to VFS.
+      See comments in do_rmdir(). Unfixed filesystems
+      will bloody likely deadlock in rmdir().
+
+Thu Dec  3 17:25:31 1998  Al Viro (viro@math.psu.edu)
+
+   * namei.c (do_rmdir):
+      Reject non-directories here.
+      Two (probably) obsolete checks moved here too: we fail if
+      the directory we remove is the same as parent (BUG: we
+      serve mountpoints later) or if it lives on a different
+      device.
+   * sysv/namei.c (sysv_rmdir):   See sysv/CHANGES
+
+Fri Dec  4 00:54:12 1998  AV
+
+   * namei.c (check_sticky): New function check_sticky(dir, inode).
+      If dir is sticky check whether we can unlink/rmdir/rename
+      the inode. Returns 1 if we can't. If dir isn't sticky -
+      return 0 (i.e. no objections). Some filesystems require
+      suser() here; some are fine with CAP_FOWNER. The later
+      seems more reasonable.
+   * namei.c (do_rmdir):
+      Moved the check for sticky bit here.
+   * affs/{inode,namei}.c:
+      All AFFS directories have sticky semantics (i.e. non-owner
+      having write permisssions on directory can unlink/rmdir/rename
+      only the files he owns), but AFFS didn't set S_ISVTX on them.
+      Fixed. NB: maybe this behaviour should be controlled by mount
+      option. Obvious values being 'sticky' (current behaviour),
+      'nonsticky' (normal behaviour) and maybe some play on 'D'
+      permissions bit. FIXME.
+   * qnx4/namei.c (qnx4_rmdir):
+      Plugged inode leak.
+   * ufs/namei.c (ufs_rmdir):
+      Changed handling of busy directory to new scheme.
+
+Fri Dec  4 10:30:58 1998  AV
+
+   * namei.c (VFS_rmdir): New function. It gets inode of the parent and
+      dentry of the victim, does all checks and applies fs-specific
+      rmdir() method. It should be called with semaphores down
+      on both the victim and its parent and with bumped d_count on
+      victim (see comments in do_rmdir).
+   * include/linux/fs.h: Added VFS_rmdir
+   * kernel/ksyms.c: Added VFS_rmdir to export list (for NFSD).
+   * nfsd/vfs.c: Fixed rmdir handling.
+
+Tue Dec  8 05:55:08 1998  AV
+   * vfat/namei.c: Fixed the bug in vfat_rename() introduced in the
+      first round of rmdir fixes.
+
+Wed Dec  9 03:06:10 1998  AV
+   * namei.c (do_rename): part of fs-independent checks had been moved
+      here (sticky bit handling, type mismatches). Cases of
+      the source or target being append-only or immutable also went
+      here - if we check it for parent we could as well do it for
+      children.
+   * {affs,ext2,minix,sysv,ufs}/namei.c (do_*_rename):
+      Removed tests that went to VFS, it simplified the code big way.
+      Fixed a race in check for empty target - we should check for
+      extra owners _before_ checking for emptiness, not after it.
+   * {ext2,ufs}/namei.c (do_*_rename):
+      VERY nasty bug shot: if somebody mkdired /tmp/cca01234, went
+      there, rmdired '.', waited till somebody created a file with
+      the same name and said mv . /tmp/goodbye_sticky_bit... Well,
+      goodbye sticky bit. Down, not across!
+   * {minix,sysv}/namei.c (do_*_rename):
+      Incorrect check for other owners (i_count instead of d_count).
+      Fixed.
+   * vfat: Looks like the changes above fixed a bug in VFAT - this beast
+      used to allow renaming file over directory and vice versa.
+
+Wed Dec  9 08:00:27 1998  AV
+   * namei.c (VFS_rename): New function. It gets the same arguments as
+      ->rename() method, does all checks and applies fs-specific
+      rmdir() method. It should be called with semaphores down
+      on both parents.
+   * include/linux/fs.h: Added VFS_rename
+   * kernel/ksyms.c: Added VFS_rename to export list (for NFSD).
+   * nfsd/vfs.c: Changed rename handling (switched to VFS_rename).
+
+Wed Dec  9 18:16:27 1998  AV
+   * namei.c (do_unlink): handling of sticky bit went here.
+   * {affs,ext2,minix,qnx4,sysv,ufs}/namei.c (*_unlink):
+      removed handling of sticky bit.
+   * qnx4/namei.c (qnx4_unlink):
+      Yet another inode leak. Fixed.
+
+Thu Dec 10 04:55:26 1998  AV
+   * {ext2,minix,sysv,ufs}/namei.c (*_mknod):
+      removed meaningless code handling attempts to mknod symlinks
+      and directories. VFS protects us from _that_ and if this code
+      would ever be called we'ld get a filesystem corruption.
+
+Thu Dec 10 16:58:50 1998  AV
+   * namei.c (do_rename): Fixed dentry leak that had been introduced by
+      the first round of rmdir fixes.
+
+Fri Dec 11 14:57:17 1998  AV
+   * msdos/namei.c (msdos_rmdir): Fixed race in emptiness check.
+
+Sat Dec 12 19:59:57 1998  AV
+   * msdos/namei.c (msdos_mkdir): Fixed the evil breakage introduced by
+      the changes of rmdir locking scheme. We shouldn't call
+      msdos_rmdir from there.
+
+Sun Dec 13 02:05:16 1998  AV
+   * namei.c (do_unlink):
+      Added new function: vfs_unlink, with the same arguments as
+      ->unlink() method.
+   * kernel/ksyms.c: Made it exported.
+   * include/linux/fs.h: Added prototype.
+   * nfsd/vfs.c: Changed handling of unlink (switched to vfs_unlink)
+   * {ext2,ufs}/namei.c (*_unlink): moved handling of imm./append-only to
+      VFS.
+
+Wed Dec 16 06:10:04 1998  AV
+   * namei.c (may_create, may_delete): New inline functions.
+      They check whether creation/deletion is permitted.
+      Checks from other places of namei.c went there.
+      Looks like originally I misread permission-related stuff
+      both here and in nfsd. In particular, checks for
+      immutable are done in permission(). D'oh.
+   * unlink on directory should return -EISDIR, not -EPERM as it used to
+      do. Fixed.
+   * rmdir of immutable/append-only directory shouldn't be allowed. Fixed.
+
+Remains unfixed:
+   * UMSDOS_rename is broken. Call it with the dest. existing and being an
+      empty directory and you've got EBUSY. At least it doesn't do
+      any harm, so that will wait several days till rename cleanup.
+      Sigh... It will wait a bit more. Problems with fat-derived
+      filesystems are much worse than I thought. Idea of changing
+      inode under dentry is broken by design - guess where the
+      semaphore sits, for one.
+   * umsdos: weird. rename() shouldn't return -EEXIST. BTW, manpage
+      for rename(2) is obviously bogus - it mentions EEXIST and
+      on the next line (correctly) says that EINVAL should be
+      returned. Under the same conditions.
+   * rename's handling of races is, erm, not optimal. Looks like I know
+      what to do, but this thing needs some more cleanup - we can
+      take care of almost all races in VFS and be much more graceful
+      wrt locking. Moreover, it would give strong lookup atomicity.
+      But it's a lot of changes to lookup and dcache code, so it will
+      go after the fs drivers' cleanup.
+   * hfs allows mknod. Only for regular files ;-/ IMHO it's bogus.
+   * affs allows HARD links to directories. VFS is, to put it politely,
+      not too ready to cope with _that_. And I'm not sure it should
+      be - looks like they are pretty much similar to symlinks.
+   * truncate doesn't give a damn about IO errors and disk overflows (on
+      braindead filesystems). I've submitted a patch to Linus, but
+      looks like it wasn't applied.
+   * msdos: shouldn't we treat SYS as IMMUTABLE? Makes sense, IMHO.
+   * minix, qnx and sysv do NOT allow to mkdir sticky directories.
+   * {minix,sysv}/namei.c (do_{minix,syv}_{rename,unlink}):
+      Stuff related to retries still needs cleanup/fixing.
+      Looks like I've found an extremely low-probability race
+      there...