From: Al Viro <viro@zeniv.linux.org.uk>
To: Jan Kara <jack@suse.cz>
Cc: linux-fsdevel@vger.kernel.org,
Linus Torvalds <torvalds@linux-foundation.org>,
Christian Brauner <brauner@kernel.org>,
Amir Goldstein <amir73il@gmail.com>,
Chuck Lever <chuck.lever@oracle.com>,
Namjae Jeon <linkinjeon@kernel.org>,
John Johansen <john@apparmor.net>,
Mark Brown <broonie@kernel.org>
Subject: Re: [PATCH 1/2] kernel/acct.c: saner struct file treatment
Date: Thu, 25 Sep 2025 19:56:30 +0100 [thread overview]
Message-ID: <20250925185630.GZ39973@ZenIV> (raw)
In-Reply-To: <klzgui6d2jo2tng5py776uku2xnwzcwi4jt5qf5iulszdtoqxo@q6o2zmvvxcuz>
On Thu, Sep 25, 2025 at 02:28:16PM +0200, Jan Kara wrote:
> This is mostly harmless (just the returned error code changed) but it is a
> side effect of one thing I'd like to discuss: The original code uses
> file_open_name(O_WRONLY|O_APPEND|O_LARGEFILE) to open the file to write
> data to. The new code uses dentry_open() for that. Now one important
> difference between these two is that dentry_open() doesn't end up calling
> may_open() on the path and hence now acct_on() fails to check file
> permissions which looks like a bug? Am I missing something Al?
You are not; a bug it is. FWIW, I suspect that the right approach would
be to keep file_open_name(), do all checks on result of that, then use
mnt = mnt_clone_internal(&original_file->f_path);
and from that point on same as now - opening the file to be used with
dentry_open(), etc. Original file would get dropped in the end of acct_on().
I'll put together something along those lines and post it.
next prev parent reply other threads:[~2025-09-25 18:56 UTC|newest]
Thread overview: 70+ messages / expand[flat|nested] mbox.gz Atom feed top
2025-09-06 9:07 [PATCHES] file->f_path safety and struct path constifications Al Viro
2025-09-06 9:11 ` [PATCH 01/21] backing_file_user_path(): constify struct path * Al Viro
2025-09-06 9:11 ` [PATCH 02/21] constify path argument of vfs_statx_path() Al Viro
2025-09-08 9:38 ` Jan Kara
2025-09-15 12:01 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 03/21] filename_lookup(): constify root argument Al Viro
2025-09-08 9:39 ` Jan Kara
2025-09-15 12:00 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 04/21] done_path_create(): constify path argument Al Viro
2025-09-08 9:40 ` Jan Kara
2025-09-15 12:01 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 05/21] bpf...d_path(): " Al Viro
2025-09-08 9:41 ` Jan Kara
2025-09-15 12:01 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 06/21] nfs: constify path argument of __vfs_getattr() Al Viro
2025-09-08 9:41 ` Jan Kara
2025-09-15 12:02 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 07/21] rqst_exp_get_by_name(): constify path argument Al Viro
2025-09-06 15:16 ` Chuck Lever
2025-09-15 12:02 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 08/21] export_operations->open(): " Al Viro
2025-09-08 9:42 ` Jan Kara
2025-09-15 12:03 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 09/21] check_export(): " Al Viro
2025-09-08 9:43 ` Jan Kara
2025-09-15 12:03 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 10/21] ksmbd_vfs_path_lookup_locked(): root_share_path can be const struct path * Al Viro
2025-09-07 1:45 ` Namjae Jeon
2025-09-15 12:03 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 11/21] ksmbd_vfs_kern_path_unlock(): constify path argument Al Viro
2025-09-07 1:44 ` Namjae Jeon
2025-09-15 12:04 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 12/21] ksmbd_vfs_inherit_posix_acl(): " Al Viro
2025-09-07 1:44 ` Namjae Jeon
2025-09-15 12:04 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 13/21] ksmbd_vfs_set_init_posix_acl(): " Al Viro
2025-09-07 1:44 ` Namjae Jeon
2025-09-15 12:04 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 14/21] ovl_ensure_verity_loaded(): constify datapath argument Al Viro
2025-09-15 12:04 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 15/21] ovl_validate_verity(): constify {meta,data}path arguments Al Viro
2025-09-15 12:05 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 16/21] ovl_get_verity_digest(): constify path argument Al Viro
2025-09-15 12:05 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 17/21] ovl_lower_dir(): " Al Viro
2025-09-15 12:05 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 18/21] ovl_sync_file(): " Al Viro
2025-09-15 12:05 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 19/21] ovl_is_real_file: constify realpath argument Al Viro
2025-09-15 12:06 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 20/21] apparmor/af_unix: constify struct path * arguments Al Viro
2025-09-08 9:46 ` Jan Kara
2025-09-15 12:06 ` Christian Brauner
2025-09-06 9:11 ` [PATCH 21/21] configfs:get_target() - release path as soon as we grab configfs_item reference Al Viro
2025-09-08 9:46 ` Jan Kara
2025-09-15 12:07 ` Christian Brauner
2025-09-08 9:38 ` [PATCH 01/21] backing_file_user_path(): constify struct path * Jan Kara
2025-09-15 11:59 ` Christian Brauner
2025-09-06 9:13 ` [PATCH 1/2] kernel/acct.c: saner struct file treatment Al Viro
2025-09-25 11:40 ` Mark Brown
2025-09-25 12:28 ` Jan Kara
2025-09-25 18:56 ` Al Viro [this message]
2025-09-25 19:09 ` Al Viro
2025-09-25 19:36 ` Al Viro
2025-09-25 20:56 ` Al Viro
2025-09-26 9:13 ` Jan Kara
2025-09-06 9:14 ` [PATCH 2/2] Have cc(1) catch attempts to modify ->f_path Al Viro
2025-09-08 9:52 ` Jan Kara
2025-09-15 12:00 ` Christian Brauner
2025-09-06 9:16 ` [PATCHES] file->f_path safety and struct path constifications Al Viro
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20250925185630.GZ39973@ZenIV \
--to=viro@zeniv.linux.org.uk \
--cc=amir73il@gmail.com \
--cc=brauner@kernel.org \
--cc=broonie@kernel.org \
--cc=chuck.lever@oracle.com \
--cc=jack@suse.cz \
--cc=john@apparmor.net \
--cc=linkinjeon@kernel.org \
--cc=linux-fsdevel@vger.kernel.org \
--cc=torvalds@linux-foundation.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).