kernel/fs/ceph/xattr.c, branch linux-6.1.y

ceph: prevent a client from exceeding the MDS maximum xattr size

2022-08-02T22:54:12Z

The MDS tries to enforce a limit on the total key/values in extended attributes. However, this limit is enforced only if doing a synchronous operation (MDS_OP_SETXATTR) -- if we're buffering the xattrs, the MDS doesn't have a chance to enforce these limits. This patch adds support for decoding the xattrs maximum size setting that is distributed in the mdsmap. Then, when setting an xattr, the kernel client will revert to do a synchronous operation if that maximum size is exceeded. While there, fix a dout() that would trigger a printk warning: [ 98.718078] ------------[ cut here ]------------ [ 98.719012] precision 65536 too large [ 98.719039] WARNING: CPU: 1 PID: 3755 at lib/vsprintf.c:2703 vsnprintf+0x5e3/0x600 ... Link: https://tracker.ceph.com/issues/55725 Signed-off-by: Luís Henriques Reviewed-by: Xiubo Li Signed-off-by: Ilya Dryomov

netfs: Fix gcc-12 warning by embedding vfs inode in netfs_i_context

2022-06-09T20:55:00Z

While randstruct was satisfied with using an open-coded "void *" offset cast for the netfs_i_context <-> inode casting, __builtin_object_size() as used by FORTIFY_SOURCE was not as easily fooled. This was causing the following complaint[1] from gcc v12: In file included from include/linux/string.h:253, from include/linux/ceph/ceph_debug.h:7, from fs/ceph/inode.c:2: In function 'fortify_memset_chk', inlined from 'netfs_i_context_init' at include/linux/netfs.h:326:2, inlined from 'ceph_alloc_inode' at fs/ceph/inode.c:463:2: include/linux/fortify-string.h:242:25: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning] 242 | __write_overflow_field(p_size_field, size); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Fix this by embedding a struct inode into struct netfs_i_context (which should perhaps be renamed to struct netfs_inode). The struct inode vfs_inode fields are then removed from the 9p, afs, ceph and cifs inode structs and vfs_inode is then simply changed to "netfs.inode" in those filesystems. Further, rename netfs_i_context to netfs_inode, get rid of the netfs_inode() function that converted a netfs_i_context pointer to an inode pointer (that can now be done with &ctx->inode) and rename the netfs_i_context() function to netfs_inode() (which is now a wrapper around container_of()). Most of the changes were done with: perl -p -i -e 's/vfs_inode/netfs.inode/'g \ `git grep -l 'vfs_inode' -- fs/{9p,afs,ceph,cifs}/*.[ch]` Kees suggested doing it with a pair structure[2] and a special declarator to insert that into the network filesystem's inode wrapper[3], but I think it's cleaner to embed it - and then it doesn't matter if struct randomisation reorders things. Dave Chinner suggested using a filesystem-specific VFS_I() function in each filesystem to convert that filesystem's own inode wrapper struct into the VFS inode struct[4]. Version #2: - Fix a couple of missed name changes due to a disabled cifs option. - Rename nfs_i_context to nfs_inode - Use "netfs" instead of "nic" as the member name in per-fs inode wrapper structs. [ This also undoes commit 507160f46c55 ("netfs: gcc-12: temporarily disable '-Wattribute-warning' for now") that is no longer needed ] Fixes: bc899ee1c898 ("netfs: Add a netfs inode context") Reported-by: Jeff Layton Signed-off-by: David Howells Reviewed-by: Jeff Layton Reviewed-by: Kees Cook Reviewed-by: Xiubo Li cc: Jonathan Corbet cc: Eric Van Hensbergen cc: Latchesar Ionkov cc: Dominique Martinet cc: Christian Schoenebeck cc: Marc Dionne cc: Ilya Dryomov cc: Steve French cc: William Kucharski cc: "Matthew Wilcox (Oracle)" cc: Dave Chinner cc: linux-doc@vger.kernel.org cc: v9fs-developer@lists.sourceforge.net cc: linux-afs@lists.infradead.org cc: ceph-devel@vger.kernel.org cc: linux-cifs@vger.kernel.org cc: samba-technical@lists.samba.org cc: linux-fsdevel@vger.kernel.org cc: linux-hardening@vger.kernel.org Link: https://lore.kernel.org/r/d2ad3a3d7bdd794c6efb562d2f2b655fb67756b9.camel@kernel.org/ [1] Link: https://lore.kernel.org/r/20220517210230.864239-1-keescook@chromium.org/ [2] Link: https://lore.kernel.org/r/20220518202212.2322058-1-keescook@chromium.org/ [3] Link: https://lore.kernel.org/r/20220524101205.GI2306852@dread.disaster.area/ [4] Link: https://lore.kernel.org/r/165296786831.3591209.12111293034669289733.stgit@warthog.procyon.org.uk/ # v1 Link: https://lore.kernel.org/r/165305805651.4094995.7763502506786714216.stgit@warthog.procyon.org.uk # v2 Signed-off-by: Linus Torvalds

ceph: allow ceph.dir.rctime xattr to be updatable

2022-05-25T18:45:13Z

`rctime' has been a pain point in cephfs due to its buggy nature - inconsistent values reported and those sorts. Fixing rctime is non-trivial needing an overall redesign of the entire nested statistics infrastructure. As a workaround, PR http://github.com/ceph/ceph/pull/37938 allows this extended attribute to be manually set. This allows users to "fixup" inconsistent rctime values. While this sounds messy, its probably the wisest approach allowing users/scripts to workaround buggy rctime values. The above PR enables Ceph MDS to allow manually setting rctime extended attribute with the corresponding user-land changes. We may as well allow the same to be done via kclient for parity. Signed-off-by: Venky Shankar Reviewed-by: Xiubo Li Signed-off-by: Ilya Dryomov

ceph: add getvxattr op

2022-03-01T17:26:37Z

Problem: Some directory vxattrs (e.g. ceph.dir.pin.random) are governed by information that isn't necessarily shared with the client. Add support for the new GETVXATTR operation, which allows the client to query the MDS directly for vxattrs. When the client is queried for a vxattr that doesn't have a special handler, have it issue a GETVXATTR to the MDS directly. Solution: Adds new getvxattr op to fetch ceph.dir.pin*, ceph.dir.layout* and ceph.file.layout* vxattrs. If the entire layout for a dir or a file is being set, then it is expected that the layout be set in standard JSON format. Individual field value retrieval is not wrapped in JSON. The JSON format also applies while setting the vxattr if the entire layout is being set in one go. As a temporary measure, setting a vxattr can also be done in the old format. The old format will be deprecated in the future. URL: https://tracker.ceph.com/issues/51062 Signed-off-by: Milind Changire Reviewed-by: Jeff Layton Signed-off-by: Ilya Dryomov

security: Return xattr name from security_dentry_init_security()

2021-10-20T12:17:08Z

Right now security_dentry_init_security() only supports single security label and is used by SELinux only. There are two users of this hook, namely ceph and nfs. NFS does not care about xattr name. Ceph hardcodes the xattr name to security.selinux (XATTR_NAME_SELINUX). I am making changes to fuse/virtiofs to send security label to virtiofsd and I need to send xattr name as well. I also hardcoded the name of xattr to security.selinux. Stephen Smalley suggested that it probably is a good idea to modify security_dentry_init_security() to also return name of xattr so that we can avoid this hardcoding in the callers. This patch adds a new parameter "const char **xattr_name" to security_dentry_init_security() and LSM puts the name of xattr too if caller asked for it (xattr_name != NULL). Signed-off-by: Vivek Goyal Reviewed-by: Jeff Layton Reviewed-by: Christian Brauner Acked-by: James Morris [PM: fixed typos in the commit description] Signed-off-by: Paul Moore

ceph: add a new vxattr to return auth mds for an inode

2021-09-02T20:49:16Z

Add a new vxattr that shows what MDS is authoritative for an inode (if we happen to have auth caps). If we don't have an auth cap for the inode then just return -1. URL: https://tracker.ceph.com/issues/1276 Signed-off-by: Jeff Layton Reviewed-by: Luis Henriques Signed-off-by: Ilya Dryomov

ceph: support getting ceph.dir.rsnaps vxattr

2021-04-27T21:52:23Z

Add support for grabbing the rsnaps value out of the inode info in traces, and exposing that via ceph.dir.rsnaps xattr. Signed-off-by: Yanhu Cao Reviewed-by: Jeff Layton Signed-off-by: Ilya Dryomov

acl: handle idmapped mounts

2021-01-24T13:27:17Z

The posix acl permission checking helpers determine whether a caller is privileged over an inode according to the acls associated with the inode. Add helpers that make it possible to handle acls on idmapped mounts. The vfs and the filesystems targeted by this first iteration make use of posix_acl_fix_xattr_from_user() and posix_acl_fix_xattr_to_user() to translate basic posix access and default permissions such as the ACL_USER and ACL_GROUP type according to the initial user namespace (or the superblock's user namespace) to and from the caller's current user namespace. Adapt these two helpers to handle idmapped mounts whereby we either map from or into the mount's user namespace depending on in which direction we're translating. Similarly, cap_convert_nscap() is used by the vfs to translate user namespace and non-user namespace aware filesystem capabilities from the superblock's user namespace to the caller's user namespace. Enable it to handle idmapped mounts by accounting for the mount's user namespace. In addition the fileystems targeted in the first iteration of this patch series make use of the posix_acl_chmod() and, posix_acl_update_mode() helpers. Both helpers perform permission checks on the target inode. Let them handle idmapped mounts. These two helpers are called when posix acls are set by the respective filesystems to handle this case we extend the ->set() method to take an additional user namespace argument to pass the mount's user namespace down. Link: https://lore.kernel.org/r/20210121131959.646623-9-christian.brauner@ubuntu.com Cc: Christoph Hellwig Cc: David Howells Cc: Al Viro Cc: linux-fsdevel@vger.kernel.org Reviewed-by: Christoph Hellwig Signed-off-by: Christian Brauner

ceph: set osdmap epoch for setxattr

2020-12-14T22:21:48Z

When setting the file/dir layout, it may need data pool info. So in mds server, it needs to check the osdmap. At present, if mds doesn't find the data pool specified, it will try to get the latest osdmap. Now if pass the osd epoch for setxattr, the mds server can only check this epoch of osdmap. URL: https://tracker.ceph.com/issues/48504 Signed-off-by: Xiubo Li Reviewed-by: Jeff Layton Signed-off-by: Ilya Dryomov

ceph: add ceph.caps vxattr

2020-12-14T22:21:48Z

Add a new vxattr that allows userspace to list the caps for a specific directory or file. [ jlayton: change format delimiter to '/' ] Signed-off-by: Luis Henriques Signed-off-by: Jeff Layton Signed-off-by: Ilya Dryomov