[GIT PULL] overlayfs fixes for 7.3

[GIT PULL] overlayfs fixes for 7.3

[Amir Goldstein]

Hi Linus,

Please pull overlayfs fixes for 7.3.

- Was in linux-next overnight

- Gone through the usual overlayfs test routines

- Includes one change in vfs code, factor out helper
  try_take_dentry_name_snapshot() with RVB from Christian

- Merges cleanly with master branch of the moment

Note that commit 8457ca071faba ("selftests/ovl: fix detached layer
mountinfo expectations") was already merged via Christain's vfs.fixes
PR from earlier today is duplicate and also on my branch.

Standard maintainers race and miscommunication. No merge conflict.
Let me know if you want me to drop this patch from my branch.

Thanks,
Amir.

----------------------------------------------------------------
The following changes since commit 214897acc8c2e5d6b63189d23ccaed6fa2af45a9:

  Revert "namei: don't reveal overmounted entries in refwalk" (2026-10-16 10:50:57 +0200)

are available in the Git repository at:

  git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs.git ovl-fixes-7.3

for you to fetch changes up to 1d27da7de3f74405b1de85ad26c5ea90f826114b:

  ovl: check the casefold flag of directories only (2026-10-29 13:40:31 +0100)

----------------------------------------------------------------
overlayfs fixes for 7.3

- Fixes for bugs found by Chris Mason's AI review, several of them
  reachable by unprivileged users: an info leak, use-after-free and NULL
  deref bugs, an RCU walk stall with remote layers and data loss with
  nfs_export

- Fix copy up of files with an empty security.capability xattr, which
  any user could set to block copy up

- Fix a regression from v6.16 with the override_creds mount option

- Two casefold fixes

----------------------------------------------------------------
Amir Goldstein (6):
      ovl: fortify ovl_copy_xattr() against underlying layer modifications
      ovl: add assertions in dir cache code
      vfs: add try_take_dentry_name_snapshot()
      ovl: skip copy up of empty security.capability
      selftests/ovl: fix detached layer mountinfo expectations
      ovl: fix mount setup failing when override_creds drops CAP_SYS_ADMIN

Chris Mason (13):
      ovl: do not copy up an xattr value that was never read
      ovl: set OVL_WHITEOUTS before publishing the upper dir
      ovl: check that the parents of volatile/dirty are dirs
      ovl: take a snapshot of the name for copy up
      ovl: do not take a name snapshot in RCU walk
      ovl: use the pinned upper dir in ovl_fix_origin()
      ovl: hold a reference on the parent in readdir
      ovl: do not copy up a dentry that was removed
      ovl: fix a torn path in ovl_get_redirect()
      ovl: read the nlink xattr of every indexed non-dir
      ovl: always encode the origin fh when index is enabled
      ovl: set the revalidate flags after d_instantiate()
      ovl: check the casefold flag of directories only

Hungyu Lin (1):
      ovl: reserve space for the casefolded name terminator

 fs/dcache.c                                        |  29 +++++-
 fs/overlayfs/copy_up.c                             | 110 +++++++++++++--------
 fs/overlayfs/dir.c                                 |  22 ++++-
 fs/overlayfs/inode.c                               |  16 ++-
 fs/overlayfs/namei.c                               |  11 ++-
 fs/overlayfs/overlayfs.h                           |   8 +-
 fs/overlayfs/readdir.c                             |  65 +++++++++---
 fs/overlayfs/super.c                               |  39 ++++++--
 include/linux/dcache.h                             |   1 +
 .../filesystems/overlayfs/set_layers_via_fds.c     |  18 ++--
 10 files changed, 233 insertions(+), 86 deletions(-)