From cbe4134ea4bc493239786220bd69cb8a13493190 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Fri, 20 Jun 2025 07:03:30 +0000 Subject: fs: export anon_inode_make_secure_inode() and fix secretmem LSM bypass 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 --- include/linux/fs.h | 2 ++ 1 file changed, 2 insertions(+) (limited to 'include/linux') diff --git a/include/linux/fs.h b/include/linux/fs.h index 4ec77da65f14..3a8e643c4279 100644 --- a/include/linux/fs.h +++ b/include/linux/fs.h @@ -3606,6 +3606,8 @@ extern int simple_write_begin(struct file *file, struct address_space *mapping, extern const struct address_space_operations ram_aops; extern int always_delete_dentry(const struct dentry *); extern struct inode *alloc_anon_inode(struct super_block *); +struct inode *anon_inode_make_secure_inode(struct super_block *sb, const char *name, + const struct inode *context_inode); extern int simple_nosetlease(struct file *, int, struct file_lease **, void **); extern const struct dentry_operations simple_dentry_operations; -- cgit v1.2.3 From 5e1e6ec2e346c0850f304c31abdef4158007474e Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 1 Jul 2025 17:38:46 +0100 Subject: netfs: Merge i_size update functions Netfslib has two functions for updating the i_size after a write: one for buffered writes into the pagecache and one for direct/unbuffered writes. However, what needs to be done is much the same in both cases, so merge them together. This does raise one question, though: should updating the i_size after a direct write do the same estimated update of i_blocks as is done for buffered writes. Also get rid of the cleanup function pointer from netfs_io_request as it's only used for direct write to update i_size; instead do the i_size setting directly from write collection. Signed-off-by: David Howells Link: https://lore.kernel.org/20250701163852.2171681-12-dhowells@redhat.com cc: Steve French cc: Paulo Alcantara cc: linux-cifs@vger.kernel.org cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner --- include/linux/netfs.h | 1 - 1 file changed, 1 deletion(-) (limited to 'include/linux') diff --git a/include/linux/netfs.h b/include/linux/netfs.h index 065c17385e53..d8186b90fb38 100644 --- a/include/linux/netfs.h +++ b/include/linux/netfs.h @@ -279,7 +279,6 @@ struct netfs_io_request { #define NETFS_RREQ_USE_PGPRIV2 31 /* [DEPRECATED] Use PG_private_2 to mark * write to cache on read */ const struct netfs_request_ops *netfs_ops; - void (*cleanup)(struct netfs_io_request *req); }; /* -- cgit v1.2.3 From 4e32541076833f5ce2e23523c9faa25f7b2cc96f Mon Sep 17 00:00:00 2001 From: David Howells Date: Tue, 1 Jul 2025 17:38:47 +0100 Subject: netfs: Renumber the NETFS_RREQ_* flags to make traces easier to read Renumber the NETFS_RREQ_* flags to put the most useful status bits in the bottom nibble - and therefore the last hex digit in the trace output - making it easier to grasp the state at a glance. In particular, put the IN_PROGRESS flag in bit 0 and ALL_QUEUED at bit 1. Also make the flags field in /proc/fs/netfs/requests larger to accommodate all the flags. Also make the flags field in the netfs_sreq tracepoint larger to accommodate all the NETFS_SREQ_* flags. Signed-off-by: David Howells Link: https://lore.kernel.org/20250701163852.2171681-13-dhowells@redhat.com Reviewed-by: Paulo Alcantara cc: netfs@lists.linux.dev cc: linux-fsdevel@vger.kernel.org Signed-off-by: Christian Brauner --- include/linux/netfs.h | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) (limited to 'include/linux') diff --git a/include/linux/netfs.h b/include/linux/netfs.h index d8186b90fb38..f43f075852c0 100644 --- a/include/linux/netfs.h +++ b/include/linux/netfs.h @@ -265,17 +265,17 @@ struct netfs_io_request { bool direct_bv_unpin; /* T if direct_bv[] must be unpinned */ refcount_t ref; unsigned long flags; -#define NETFS_RREQ_OFFLOAD_COLLECTION 0 /* Offload collection to workqueue */ -#define NETFS_RREQ_NO_UNLOCK_FOLIO 2 /* Don't unlock no_unlock_folio on completion */ -#define NETFS_RREQ_FAILED 4 /* The request failed */ -#define NETFS_RREQ_IN_PROGRESS 5 /* Unlocked when the request completes (has ref) */ -#define NETFS_RREQ_FOLIO_COPY_TO_CACHE 6 /* Copy current folio to cache from read */ -#define NETFS_RREQ_UPLOAD_TO_SERVER 8 /* Need to write to the server */ -#define NETFS_RREQ_PAUSE 11 /* Pause subrequest generation */ +#define NETFS_RREQ_IN_PROGRESS 0 /* Unlocked when the request completes (has ref) */ +#define NETFS_RREQ_ALL_QUEUED 1 /* All subreqs are now queued */ +#define NETFS_RREQ_PAUSE 2 /* Pause subrequest generation */ +#define NETFS_RREQ_FAILED 3 /* The request failed */ +#define NETFS_RREQ_RETRYING 4 /* Set if we're in the retry path */ +#define NETFS_RREQ_SHORT_TRANSFER 5 /* Set if we have a short transfer */ +#define NETFS_RREQ_OFFLOAD_COLLECTION 8 /* Offload collection to workqueue */ +#define NETFS_RREQ_NO_UNLOCK_FOLIO 9 /* Don't unlock no_unlock_folio on completion */ +#define NETFS_RREQ_FOLIO_COPY_TO_CACHE 10 /* Copy current folio to cache from read */ +#define NETFS_RREQ_UPLOAD_TO_SERVER 11 /* Need to write to the server */ #define NETFS_RREQ_USE_IO_ITER 12 /* Use ->io_iter rather than ->i_pages */ -#define NETFS_RREQ_ALL_QUEUED 13 /* All subreqs are now queued */ -#define NETFS_RREQ_RETRYING 14 /* Set if we're in the retry path */ -#define NETFS_RREQ_SHORT_TRANSFER 15 /* Set if we have a short transfer */ #define NETFS_RREQ_USE_PGPRIV2 31 /* [DEPRECATED] Use PG_private_2 to mark * write to cache on read */ const struct netfs_request_ops *netfs_ops; -- cgit v1.2.3