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(cst-prg-84-1.cust.vodafone.cz. [46.135.84.1]) by smtp.gmail.com with ESMTPSA id 5b1f17b1804b1-49e6420de77sm109534235e9.3.2026.09.13.07.49.46 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 13 Sep 2026 07:49:47 -0700 (PDT) From: Mateusz Guzik To: brauner@kernel.org Cc: viro@zeniv.linux.org.uk, jack@suse.cz, linux-kernel@vger.kernel.org, linux-fsdevel@vger.kernel.org, Mateusz Guzik Subject: [PATCH 00/10] Towards safer path_* API Date: Sun, 13 Sep 2026 16:49:07 +0200 Message-ID: <20260913144918.1606123-1-mjguzik@gmail.com> X-Mailer: git-send-email 2.43.0 Precedence: bulk X-Mailing-List: linux-fsdevel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Currently the handling is highly error-prone with consumers allowed to arbitrarily manipulate references, notably with path_get(). In the past this resulted in preventable bugs. The end goal, not yet achieved with this patchset, will provide an invariant that a populated 'struct path' has precisely one set of references on it. While consumers can still cause leaks by neglecting to path_put(), the footgun of path_get() can be eliminated. With this patchset instead of hand-rolling a path copy and issuing path_get() on it, callers can resort to path_clone() instead. Almost all path_get() consumers get converted, most of which with coccinelle. Few instances are left until I figure out a nice way to sort them out. Overall almost entirety of this patchset is a NOP. Mateusz Guzik (10): fs: unexport backing_file_set_user_path() and make it take the ref on its own fs: add path_create(), path_move() and path_clone() fs: use path_clone() in path_init() fs: use path_clone() and path_move() in vfs_open* fs: use path_clone() in backing_file_set_user_path() Coccinelle-based conversion of path_* consumers to use the new primitives autofs: use path_create() fsnotify: use path_clone() proc: use path_clone() nfsd: use path_clone() drivers/block/loop.c | 3 +- fs/autofs/dev-ioctl.c | 3 +- fs/autofs/expire.c | 4 +-- fs/backing-file.c | 2 -- fs/devpts/inode.c | 6 ++-- fs/failfs.c | 3 +- fs/fhandle.c | 3 +- fs/file_attr.c | 6 ++-- fs/file_table.c | 3 +- fs/fs_struct.c | 6 ++-- fs/namei.c | 44 ++++++++++++++++++++++++------ fs/namespace.c | 3 +- fs/nfsd/export.c | 6 ++-- fs/nfsd/nfs4xdr.c | 8 +++--- fs/notify/fanotify/fanotify.c | 6 ++-- fs/notify/fanotify/fanotify_user.c | 3 +- fs/nsfs.c | 3 +- fs/open.c | 10 ++----- fs/overlayfs/params.c | 3 +- fs/pidfs.c | 3 +- fs/proc/base.c | 6 ++-- fs/proc/fd.c | 3 +- fs/smb/server/vfs.c | 3 +- fs/xfs/xfs_handle.c | 3 +- include/linux/path.h | 14 ++++++++-- kernel/trace/bpf_trace.c | 3 +- security/apparmor/task.c | 3 +- security/keys/big_key.c | 3 +- security/landlock/fs.c | 3 +- security/landlock/syscalls.c | 3 +- 30 files changed, 87 insertions(+), 85 deletions(-) -- 2.53.0