ovl: do not encode lower fh with upper sb_writers held

Browse source

[ Upstream commit 5b02bfc1e7 ]

When lower fs is a nested overlayfs, calling encode_fh() on a lower
directory dentry may trigger copy up and take sb_writers on the upper fs
of the lower nested overlayfs.

The lower nested overlayfs may have the same upper fs as this overlayfs,
so nested sb_writers lock is illegal.

Move all the callers that encode lower fh to before ovl_want_write().

Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Stable-dep-of: c45beebfde ("ovl: support encoding fid from inode with no alias")
Signed-off-by: Sasha Levin <sashal@kernel.org>

...

This commit is contained in:

Amir Goldstein 2023-08-16 16:47:59 +03:00 • committed by Greg Kroah-Hartman

parent 1e92afe801

commit 26423e18cd

5 changed files with 104 additions and 42 deletions

Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL

Download patch file Download diff file Expand all files Collapse all files

53

fs/overlayfs/copy_up.c

View file

37

fs/overlayfs/namei.c

View file

26

fs/overlayfs/overlayfs.h

View file

20

fs/overlayfs/super.c

View file

10

fs/overlayfs/util.c

View file