From 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 Mon Sep 17 00:00:00 2001 From: Daniel Baumann Date: Sat, 27 Apr 2024 12:05:51 +0200 Subject: Adding upstream version 5.10.209. Signed-off-by: Daniel Baumann --- fs/nfs/nfs3acl.c | 344 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 344 insertions(+) create mode 100644 fs/nfs/nfs3acl.c (limited to 'fs/nfs/nfs3acl.c') diff --git a/fs/nfs/nfs3acl.c b/fs/nfs/nfs3acl.c new file mode 100644 index 000000000..c6c863382 --- /dev/null +++ b/fs/nfs/nfs3acl.c @@ -0,0 +1,344 @@ +// SPDX-License-Identifier: GPL-2.0 +#include +#include +#include +#include +#include +#include +#include + +#include "internal.h" +#include "nfs3_fs.h" + +#define NFSDBG_FACILITY NFSDBG_PROC + +/* + * nfs3_prepare_get_acl, nfs3_complete_get_acl, nfs3_abort_get_acl: Helpers for + * caching get_acl results in a race-free way. See fs/posix_acl.c:get_acl() + * for explanations. + */ +static void nfs3_prepare_get_acl(struct posix_acl **p) +{ + struct posix_acl *sentinel = uncached_acl_sentinel(current); + + if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) { + /* Not the first reader or sentinel already in place. */ + } +} + +static void nfs3_complete_get_acl(struct posix_acl **p, struct posix_acl *acl) +{ + struct posix_acl *sentinel = uncached_acl_sentinel(current); + + /* Only cache the ACL if our sentinel is still in place. */ + posix_acl_dup(acl); + if (cmpxchg(p, sentinel, acl) != sentinel) + posix_acl_release(acl); +} + +static void nfs3_abort_get_acl(struct posix_acl **p) +{ + struct posix_acl *sentinel = uncached_acl_sentinel(current); + + /* Remove our sentinel upon failure. */ + cmpxchg(p, sentinel, ACL_NOT_CACHED); +} + +struct posix_acl *nfs3_get_acl(struct inode *inode, int type) +{ + struct nfs_server *server = NFS_SERVER(inode); + struct page *pages[NFSACL_MAXPAGES] = { }; + struct nfs3_getaclargs args = { + .fh = NFS_FH(inode), + /* The xdr layer may allocate pages here. */ + .pages = pages, + }; + struct nfs3_getaclres res = { + NULL, + }; + struct rpc_message msg = { + .rpc_argp = &args, + .rpc_resp = &res, + }; + int status, count; + + if (!nfs_server_capable(inode, NFS_CAP_ACLS)) + return ERR_PTR(-EOPNOTSUPP); + + status = nfs_revalidate_inode(server, inode); + if (status < 0) + return ERR_PTR(status); + + /* + * Only get the access acl when explicitly requested: We don't + * need it for access decisions, and only some applications use + * it. Applications which request the access acl first are not + * penalized from this optimization. + */ + if (type == ACL_TYPE_ACCESS) + args.mask |= NFS_ACLCNT|NFS_ACL; + if (S_ISDIR(inode->i_mode)) + args.mask |= NFS_DFACLCNT|NFS_DFACL; + if (args.mask == 0) + return NULL; + + dprintk("NFS call getacl\n"); + msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_GETACL]; + res.fattr = nfs_alloc_fattr(); + if (res.fattr == NULL) + return ERR_PTR(-ENOMEM); + + if (args.mask & NFS_ACL) + nfs3_prepare_get_acl(&inode->i_acl); + if (args.mask & NFS_DFACL) + nfs3_prepare_get_acl(&inode->i_default_acl); + + status = rpc_call_sync(server->client_acl, &msg, 0); + dprintk("NFS reply getacl: %d\n", status); + + /* pages may have been allocated at the xdr layer. */ + for (count = 0; count < NFSACL_MAXPAGES && args.pages[count]; count++) + __free_page(args.pages[count]); + + switch (status) { + case 0: + status = nfs_refresh_inode(inode, res.fattr); + break; + case -EPFNOSUPPORT: + case -EPROTONOSUPPORT: + dprintk("NFS_V3_ACL extension not supported; disabling\n"); + server->caps &= ~NFS_CAP_ACLS; + fallthrough; + case -ENOTSUPP: + status = -EOPNOTSUPP; + default: + goto getout; + } + if ((args.mask & res.mask) != args.mask) { + status = -EIO; + goto getout; + } + + if (res.acl_access != NULL) { + if ((posix_acl_equiv_mode(res.acl_access, NULL) == 0) || + res.acl_access->a_count == 0) { + posix_acl_release(res.acl_access); + res.acl_access = NULL; + } + } + + if (res.mask & NFS_ACL) + nfs3_complete_get_acl(&inode->i_acl, res.acl_access); + else + forget_cached_acl(inode, ACL_TYPE_ACCESS); + + if (res.mask & NFS_DFACL) + nfs3_complete_get_acl(&inode->i_default_acl, res.acl_default); + else + forget_cached_acl(inode, ACL_TYPE_DEFAULT); + + nfs_free_fattr(res.fattr); + if (type == ACL_TYPE_ACCESS) { + posix_acl_release(res.acl_default); + return res.acl_access; + } else { + posix_acl_release(res.acl_access); + return res.acl_default; + } + +getout: + nfs3_abort_get_acl(&inode->i_acl); + nfs3_abort_get_acl(&inode->i_default_acl); + posix_acl_release(res.acl_access); + posix_acl_release(res.acl_default); + nfs_free_fattr(res.fattr); + return ERR_PTR(status); +} + +static int __nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl, + struct posix_acl *dfacl) +{ + struct nfs_server *server = NFS_SERVER(inode); + struct nfs_fattr *fattr; + struct page *pages[NFSACL_MAXPAGES]; + struct nfs3_setaclargs args = { + .inode = inode, + .mask = NFS_ACL, + .acl_access = acl, + .pages = pages, + }; + struct rpc_message msg = { + .rpc_argp = &args, + .rpc_resp = &fattr, + }; + int status = 0; + + if (acl == NULL && (!S_ISDIR(inode->i_mode) || dfacl == NULL)) + goto out; + + status = -EOPNOTSUPP; + if (!nfs_server_capable(inode, NFS_CAP_ACLS)) + goto out; + + /* We are doing this here because XDR marshalling does not + * return any results, it BUGs. */ + status = -ENOSPC; + if (acl != NULL && acl->a_count > NFS_ACL_MAX_ENTRIES) + goto out; + if (dfacl != NULL && dfacl->a_count > NFS_ACL_MAX_ENTRIES) + goto out; + if (S_ISDIR(inode->i_mode)) { + args.mask |= NFS_DFACL; + args.acl_default = dfacl; + args.len = nfsacl_size(acl, dfacl); + } else + args.len = nfsacl_size(acl, NULL); + + if (args.len > NFS_ACL_INLINE_BUFSIZE) { + unsigned int npages = 1 + ((args.len - 1) >> PAGE_SHIFT); + + status = -ENOMEM; + do { + args.pages[args.npages] = alloc_page(GFP_KERNEL); + if (args.pages[args.npages] == NULL) + goto out_freepages; + args.npages++; + } while (args.npages < npages); + } + + dprintk("NFS call setacl\n"); + status = -ENOMEM; + fattr = nfs_alloc_fattr(); + if (fattr == NULL) + goto out_freepages; + + msg.rpc_proc = &server->client_acl->cl_procinfo[ACLPROC3_SETACL]; + msg.rpc_resp = fattr; + status = rpc_call_sync(server->client_acl, &msg, 0); + nfs_access_zap_cache(inode); + nfs_zap_acl_cache(inode); + dprintk("NFS reply setacl: %d\n", status); + + switch (status) { + case 0: + status = nfs_refresh_inode(inode, fattr); + break; + case -EPFNOSUPPORT: + case -EPROTONOSUPPORT: + dprintk("NFS_V3_ACL SETACL RPC not supported" + "(will not retry)\n"); + server->caps &= ~NFS_CAP_ACLS; + fallthrough; + case -ENOTSUPP: + status = -EOPNOTSUPP; + } + nfs_free_fattr(fattr); +out_freepages: + while (args.npages != 0) { + args.npages--; + __free_page(args.pages[args.npages]); + } +out: + return status; +} + +int nfs3_proc_setacls(struct inode *inode, struct posix_acl *acl, + struct posix_acl *dfacl) +{ + int ret; + ret = __nfs3_proc_setacls(inode, acl, dfacl); + return (ret == -EOPNOTSUPP) ? 0 : ret; + +} + +int nfs3_set_acl(struct inode *inode, struct posix_acl *acl, int type) +{ + struct posix_acl *orig = acl, *dfacl = NULL, *alloc; + int status; + + if (S_ISDIR(inode->i_mode)) { + switch(type) { + case ACL_TYPE_ACCESS: + alloc = get_acl(inode, ACL_TYPE_DEFAULT); + if (IS_ERR(alloc)) + goto fail; + dfacl = alloc; + break; + + case ACL_TYPE_DEFAULT: + alloc = get_acl(inode, ACL_TYPE_ACCESS); + if (IS_ERR(alloc)) + goto fail; + dfacl = acl; + acl = alloc; + break; + } + } + + if (acl == NULL) { + alloc = posix_acl_from_mode(inode->i_mode, GFP_KERNEL); + if (IS_ERR(alloc)) + goto fail; + acl = alloc; + } + status = __nfs3_proc_setacls(inode, acl, dfacl); +out: + if (acl != orig) + posix_acl_release(acl); + if (dfacl != orig) + posix_acl_release(dfacl); + return status; + +fail: + status = PTR_ERR(alloc); + goto out; +} + +const struct xattr_handler *nfs3_xattr_handlers[] = { + &posix_acl_access_xattr_handler, + &posix_acl_default_xattr_handler, + NULL, +}; + +static int +nfs3_list_one_acl(struct inode *inode, int type, const char *name, void *data, + size_t size, ssize_t *result) +{ + struct posix_acl *acl; + char *p = data + *result; + + acl = get_acl(inode, type); + if (IS_ERR_OR_NULL(acl)) + return 0; + + posix_acl_release(acl); + + *result += strlen(name); + *result += 1; + if (!size) + return 0; + if (*result > size) + return -ERANGE; + + strcpy(p, name); + return 0; +} + +ssize_t +nfs3_listxattr(struct dentry *dentry, char *data, size_t size) +{ + struct inode *inode = d_inode(dentry); + ssize_t result = 0; + int error; + + error = nfs3_list_one_acl(inode, ACL_TYPE_ACCESS, + XATTR_NAME_POSIX_ACL_ACCESS, data, size, &result); + if (error) + return error; + + error = nfs3_list_one_acl(inode, ACL_TYPE_DEFAULT, + XATTR_NAME_POSIX_ACL_DEFAULT, data, size, &result); + if (error) + return error; + return result; +} -- cgit v1.2.3