linux-stable.git/fs/overlayfs, branch linux-6.11.y

fs: pass offset and result to backing_file end_write() callback

2024-11-01T01:02:38+00:00

[ Upstream commit f03b296e8b516dbd63f57fc9056c1b0da1b9a0ff ]

This is needed for extending fuse inode size after fuse passthrough write.

Suggested-by: Miklos Szeredi 
Link: https://lore.kernel.org/linux-fsdevel/CAJfpegs=cvZ_NYy6Q_D42XhYS=Sjj5poM1b5TzXzOVvX=R36aA@mail.gmail.com/
Signed-off-by: Amir Goldstein 
Signed-off-by: Miklos Szeredi 
Stable-dep-of: 20121d3f58f0 ("fuse: update inode size after extending passthrough write")
Signed-off-by: Sasha Levin

ovl: fail if trusted xattrs are needed but caller lacks permission

2024-10-10T10:03:47+00:00

commit 6c4a5f96450415735c31ed70ff354f0ee5cbf67b upstream.

Some overlayfs features require permission to read/write trusted.*
xattrs. These include redirect_dir, verity, metacopy, and data-only
layers. This patch adds additional validations at mount time to stop
overlays from mounting in certain cases where the resulting mount would
not function according to the user's expectations because they lack
permission to access trusted.* xattrs (for example, not global root.)

Similar checks in ovl_make_workdir() that disable features instead of
failing are still relevant and used in cases where the resulting mount
can still work "reasonably well." Generally, if the feature was enabled
through kernel config or module option, any mount that worked before
will still work the same; this applies to redirect_dir and metacopy. The
user must explicitly request these features in order to generate a mount
failure. Verity and data-only layers on the other hand must be explictly
requested and have no "reasonable" disabled or degraded alternative, so
mounts attempting either always fail.

"lower data-only dirs require metacopy support" moved down in case
userxattr is set, which disables metacopy.

Cc: stable@vger.kernel.org # v6.6+
Signed-off-by: Mike Baynton 
Signed-off-by: Amir Goldstein 
Signed-off-by: Greg Kroah-Hartman

ovl: fsync after metadata copy-up

2024-10-10T10:03:37+00:00

[ Upstream commit 7d6899fb69d25e1bc6f4700b7c1d92e6b608593d ]

For upper filesystems which do not use strict ordering of persisting
metadata changes (e.g. ubifs), when overlayfs file is modified for
the first time, copy up will create a copy of the lower file and
its parent directories in the upper layer. Permission lost of the
new upper parent directory was observed during power-cut stress test.

Fix by moving the fsync call to after metadata copy to make sure that the
metadata copied up directory and files persists to disk before renaming
from tmp to final destination.

With metacopy enabled, this change will hurt performance of workloads
such as chown -R, so we keep the legacy behavior of fsync only on copyup
of data.

Link: https://lore.kernel.org/linux-unionfs/CAOQ4uxj-pOvmw1-uXR3qVdqtLjSkwcR9nVKcNU_vC10Zyf2miQ@mail.gmail.com/
Reported-and-tested-by: Fei Lv 
Signed-off-by: Amir Goldstein 
Signed-off-by: Sasha Levin

Merge patch series "ovl: simplify ovl_parse_param_lowerdir()"

2024-08-24T14:00:46+00:00

Simplify and fix overlayfs layer parsing so the maximum of 500 layers
can be used.

* patches from https://lore.kernel.org/r/20240705011510.794025-1-chengzhihao1@huawei.com:
  ovl: ovl_parse_param_lowerdir: Add missed '\n' for pr_err
  ovl: fix wrong lowerdir number check for parameter Opt_lowerdir
  ovl: pass string to ovl_parse_layer()

Link: https://lore.kernel.org/r/20240705011510.794025-1-chengzhihao1@huawei.com
Signed-off-by: Christian Brauner

ovl: ovl_parse_param_lowerdir: Add missed '\n' for pr_err

2024-08-23T17:58:59+00:00

Add '\n' for pr_err in function ovl_parse_param_lowerdir(), which
ensures that error message is displayed at once.

Fixes: b36a5780cb44 ("ovl: modify layer parameter parsing")
Signed-off-by: Zhihao Cheng 
Link: https://lore.kernel.org/r/20240705011510.794025-4-chengzhihao1@huawei.com
Signed-off-by: Christian Brauner

ovl: fix wrong lowerdir number check for parameter Opt_lowerdir

2024-08-23T17:56:38+00:00

The max count of lowerdir is OVL_MAX_STACK[500], which is broken by
commit 37f32f526438("ovl: fix memory leak in ovl_parse_param()") for
parameter Opt_lowerdir. Since commit 819829f0319a("ovl: refactor layer
parsing helpers") and commit 24e16e385f22("ovl: add support for
appending lowerdirs one by one") added check ovl_mount_dir_check() in
function ovl_parse_param_lowerdir(), the 'ctx->nr' should be smaller
than OVL_MAX_STACK, after commit 37f32f526438("ovl: fix memory leak in
ovl_parse_param()") is applied, the 'ctx->nr' is updated before the
check ovl_mount_dir_check(), which leads the max count of lowerdir
to become 499 for parameter Opt_lowerdir.
Fix it by replacing lower layers parsing code with the existing helper
function ovl_parse_layer().

Fixes: 37f32f526438 ("ovl: fix memory leak in ovl_parse_param()")
Signed-off-by: Zhihao Cheng 
Link: https://lore.kernel.org/r/20240705011510.794025-3-chengzhihao1@huawei.com
Reviewed-by: Amir Goldstein 
Signed-off-by: Christian Brauner

ovl: pass string to ovl_parse_layer()

2024-08-23T17:56:38+00:00

So it can be used for parsing the Opt_lowerdir.

Signed-off-by: Zhihao Cheng 
Link: https://lore.kernel.org/r/20240705011510.794025-2-chengzhihao1@huawei.com
Signed-off-by: Christian Brauner

ovl: fix encoding fid for lower only root

2024-06-14T08:30:40+00:00

ovl_check_encode_origin() should return a positive number if the lower
dentry is to be encoded, zero otherwise.  If there's no upper layer at all
(read-only overlay), then it obviously needs to return positive.

This was broken by commit 16aac5ad1fa9 ("ovl: support encoding
non-decodable file handles"), which didn't take the lower-only
configuration into account.

Fix by checking the no-upper-layer case up-front.

Reported-and-tested-by: Youzhong Yang 
Closes: https://lore.kernel.org/all/CADpNCvaBimi+zCYfRJHvCOhMih8OU0rmZkwLuh24MKKroRuT8Q@mail.gmail.com/
Fixes: 16aac5ad1fa9 ("ovl: support encoding non-decodable file handles")
Cc:  # v6.6
Signed-off-by: Miklos Szeredi

ovl: fix copy-up in tmpfile

2024-05-28T08:06:55+00:00

Move ovl_copy_up() call outside of ovl_want_write()/ovl_drop_write()
region, since copy up may also call ovl_want_write() resulting in recursive
locking on sb->s_writers.

Reported-and-tested-by: syzbot+85e58cdf5b3136471d4b@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/000000000000f6865106191c3e58@google.com/
Fixes: 9a87907de359 ("ovl: implement tmpfile")
Signed-off-by: Miklos Szeredi

Merge tag 'ovl-update-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs

2024-05-22T16:23:18+00:00

Pull overlayfs updates from Miklos Szeredi:

 - Add tmpfile support

 - Clean up include

* tag 'ovl-update-6.10' of git://git.kernel.org/pub/scm/linux/kernel/git/overlayfs/vfs:
  ovl: remove duplicate included header
  ovl: remove upper umask handling from ovl_create_upper()
  ovl: implement tmpfile