[git pull] d_revalidate pile (v2)

Al Viro
2025-01-30T04:37:09Z

->d_revalidate() series, along with ->d_iname preliminary work.
One trivial conflict in fs/afs/dir.c - afs_do_lookup_one() has lost
one argument in mainline and switched another from dentry to qstr
in this series.

Change since the previous variant: made external_name.name word-aligned
and explicitly documented the layout constraints for struct external_name.

The following changes since commit 40384c840ea1944d7c5a392e8975ed088ecf0b37:

Linux 6.13-rc1 (2024-12-01 14:28:56 -0800)

are available in the Git repository at:

git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs.git tags/pull-revalidate

for you to fetch changes up to 30d61efe118cad1a73ad2ad66a3298e4abdf9f41:

9p: fix ->rename_sem exclusion (2025-01-27 19:25:24 -0500)

----------------------------------------------------------------
Provide stable parent and name to ->d_revalidate() instances

Most of the filesystem methods where we care about dentry name
and parent have their stability guaranteed by the callers;
->d_revalidate() is the major exception.

It's easy enough for callers to supply stable values for
expected name and expected parent of the dentry being
validated. That kills quite a bit of boilerplate in
->d_revalidate() instances, along with a bunch of races
where they used to access ->d_name without sufficient
precautions.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

----------------------------------------------------------------
Al Viro (20):
make sure that DNAME_INLINE_LEN is a multiple of word size
dcache: back inline names with a struct-wrapped array of unsigned long
make take_dentry_name_snapshot() lockless
dissolve external_name.u into separate members
ext4 fast_commit: make use of name_snapshot primitives
generic_ci_d_compare(): use shortname_storage
Pass parent directory inode and expected name to ->d_revalidate()
afs_d_revalidate(): use stable name and parent inode passed by caller
ceph_d_revalidate(): use stable parent inode passed by caller
ceph_d_revalidate(): propagate stable name down into request encoding
fscrypt_d_revalidate(): use stable parent inode passed by caller
exfat_d_revalidate(): use stable parent inode passed by caller
vfat_revalidate{,_ci}(): use stable parent inode passed by caller
fuse_dentry_revalidate(): use stable parent inode and name passed by caller
gfs2_drevalidate(): use stable parent inode and name passed by caller
nfs{,4}_lookup_validate(): use stable parent inode passed by caller
nfs: fix ->d_revalidate() UAF on ->d_name accesses
ocfs2_dentry_revalidate(): use stable parent inode and name passed by caller
orangefs_d_revalidate(): use stable parent inode and name passed by caller
9p: fix ->rename_sem exclusion

Documentation/filesystems/locking.rst | 7 +-
Documentation/filesystems/porting.rst | 16 +++++
Documentation/filesystems/vfs.rst | 24 ++++++-
fs/9p/v9fs.h | 2 +-
fs/9p/vfs_dentry.c | 26 ++++++-
fs/afs/dir.c | 40 ++++-------
fs/ceph/dir.c | 25 ++-----
fs/ceph/mds_client.c | 9 ++-
fs/ceph/mds_client.h | 2 +
fs/coda/dir.c | 3 +-
fs/crypto/fname.c | 22 ++----
fs/dcache.c | 103 ++++++++++++++++-----------
fs/ecryptfs/dentry.c | 18 +++--
fs/exfat/namei.c | 11 +--
fs/ext4/fast_commit.c | 29 ++------
fs/ext4/fast_commit.h | 3 +-
fs/fat/namei_vfat.c | 19 +++--
fs/fuse/dir.c | 20 +++---
fs/gfs2/dentry.c | 31 ++++----
fs/hfs/sysdep.c | 3 +-
fs/jfs/namei.c | 3 +-
fs/kernfs/dir.c | 3 +-
fs/libfs.c | 15 ++--
fs/namei.c | 18 ++---
fs/nfs/dir.c | 62 +++++++---------
fs/nfs/namespace.c | 2 +-
fs/nfs/nfs3proc.c | 5 +-
fs/nfs/nfs4proc.c | 20 +++---
fs/nfs/proc.c | 6 +-
fs/ocfs2/dcache.c | 14 ++--
fs/orangefs/dcache.c | 22 +++---
fs/overlayfs/super.c | 22 +++++-
fs/proc/base.c | 6 +-
fs/proc/fd.c | 3 +-
fs/proc/generic.c | 6 +-
fs/proc/proc_sysctl.c | 3 +-
fs/smb/client/dir.c | 3 +-
fs/tracefs/inode.c | 3 +-
fs/vboxsf/dir.c | 3 +-
include/linux/dcache.h | 23 ++++--
include/linux/fscrypt.h | 7 +-
include/linux/nfs_xdr.h | 2 +-
tools/testing/selftests/bpf/progs/find_vma.c | 2 +-
43 files changed, 359 insertions(+), 307 deletions(-)