kernel/linux.git/fs/anon_inodes.c, branch v6.6.141

fs: export anon_inode_make_secure_inode() and fix secretmem LSM bypass

2025-07-10T14:03:18+00:00

[ Upstream commit cbe4134ea4bc493239786220bd69cb8a13493190 ] Export anon_inode_make_secure_inode() to allow KVM guest_memfd to create anonymous inodes with proper security context. This replaces the current pattern of calling alloc_anon_inode() followed by inode_init_security_anon() for creating security context manually. This change also fixes a security regression in secretmem where the S_PRIVATE flag was not cleared after alloc_anon_inode(), causing LSM/SELinux checks to be bypassed for secretmem file descriptors. As guest_memfd currently resides in the KVM module, we need to export this symbol for use outside the core kernel. In the future, guest_memfd might be moved to core-mm, at which point the symbols no longer would have to be exported. When/if that happens is still unclear. Fixes: 2bfe15c52612 ("mm: create security context for memfd_secret inodes") Suggested-by: David Hildenbrand Suggested-by: Mike Rapoport Signed-off-by: Shivank Garg Link: https://lore.kernel.org/20250620070328.803704-3-shivankg@amd.com Acked-by: "Mike Rapoport (Microsoft)" Signed-off-by: Christian Brauner Signed-off-by: Sasha Levin

dynamic_dname(): drop unused dentry argument

2022-08-20T15:34:04+00:00

Signed-off-by: Al Viro

fs: add anon_inode_getfile_secure() similar to anon_inode_getfd_secure()

2021-09-20T02:35:37+00:00

Extending the secure anonymous inode support to other subsystems requires that we have a secure anon_inode_getfile() variant in addition to the existing secure anon_inode_getfd() variant. Thankfully we can reuse the existing __anon_inode_getfile() function and just wrap it with the proper arguments. Acked-by: Mickaël Salaün Signed-off-by: Paul Moore

fs: anon_inodes: rephrase to appropriate kernel-doc

2021-01-15T17:17:25+00:00

Commit e7e832ce6fa7 ("fs: add LSM-supporting anon-inode interface") adds more kerneldoc description, but also a few new warnings on anon_inode_getfd_secure() due to missing parameter descriptions. Rephrase to appropriate kernel-doc for anon_inode_getfd_secure(). Signed-off-by: Lukas Bulwahn Signed-off-by: Paul Moore

fs: add LSM-supporting anon-inode interface

2021-01-14T22:31:05+00:00

This change adds a new function, anon_inode_getfd_secure, that creates anonymous-node file with individual non-S_PRIVATE inode to which security modules can apply policy. Existing callers continue using the original singleton-inode kind of anonymous-inode file. We can transition anonymous inode users to the new kind of anonymous inode in individual patches for the sake of bisection and review. The new function accepts an optional context_inode parameter that callers can use to provide additional contextual information to security modules. For example, in case of userfaultfd, the created inode is a 'logical child' of the context_inode (userfaultfd inode of the parent process) in the sense that it provides the security context required during creation of the child process' userfaultfd inode. Signed-off-by: Daniel Colascione [LG: Delete obsolete comments to alloc_anon_inode()] [LG: Add context_inode description in comments to anon_inode_getfd_secure()] [LG: Remove definition of anon_inode_getfile_secure() as there are no callers] [LG: Make __anon_inode_getfile() static] [LG: Use correct error cast in __anon_inode_getfile()] [LG: Fix error handling in __anon_inode_getfile()] Signed-off-by: Lokesh Gidra Reviewed-by: Eric Biggers Signed-off-by: Paul Moore

Merge branch 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs

2019-07-19T17:42:02+00:00

Pull vfs mount updates from Al Viro: "The first part of mount updates. Convert filesystems to use the new mount API" * 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits) mnt_init(): call shmem_init() unconditionally constify ksys_mount() string arguments don't bother with registering rootfs init_rootfs(): don't bother with init_ramfs_fs() vfs: Convert smackfs to use the new mount API vfs: Convert selinuxfs to use the new mount API vfs: Convert securityfs to use the new mount API vfs: Convert apparmorfs to use the new mount API vfs: Convert openpromfs to use the new mount API vfs: Convert xenfs to use the new mount API vfs: Convert gadgetfs to use the new mount API vfs: Convert oprofilefs to use the new mount API vfs: Convert ibmasmfs to use the new mount API vfs: Convert qib_fs/ipathfs to use the new mount API vfs: Convert efivarfs to use the new mount API vfs: Convert configfs to use the new mount API vfs: Convert binfmt_misc to use the new mount API convenience helper: get_tree_single() convenience helper get_tree_nodev() vfs: Kill sget_userns() ...

vfs: Convert anon_inodes to use the new mount API

2019-05-25T22:00:05+00:00

Convert the anon_inodes filesystem to the new internal mount API as the old one will be obsoleted and removed. This allows greater flexibility in communication of mount parameters between userspace, the VFS and the filesystem. See Documentation/filesystems/mount_api.txt for more information. Signed-off-by: David Howells cc: linux-fsdevel@vger.kernel.org Signed-off-by: Al Viro

mount_pseudo(): drop 'name' argument, switch to d_make_root()

2019-05-25T21:59:24+00:00

Once upon a time we used to set ->d_name of e.g. pipefs root so that d_path() on pipes would work. These days it's completely pointless - dentries of pipes are not even connected to pipefs root. However, mount_pseudo() had set the root dentry name (passed as the second argument) and callers kept inventing names to pass to it. Including those that didn't *have* any non-root dentries to start with... All of that had been pointless for about 8 years now; it's time to get rid of that cargo-culting... Signed-off-by: Al Viro

treewide: Add SPDX license identifier for missed files

2019-05-21T08:50:45+00:00

Add SPDX license identifiers to all files which: - Have no license information of any form - Have EXPORT_.*_SYMBOL_GPL inside which was used in the initial scan/conversion to ignore the file These files fall under the project license, GPL v2 only. The resulting SPDX license identifier is: GPL-2.0-only Signed-off-by: Thomas Gleixner Signed-off-by: Greg Kroah-Hartman

anon_inode_getfile(): switch to alloc_file_pseudo()

2018-07-12T14:04:27+00:00

Acked-by: Linus Torvalds Signed-off-by: Al Viro