From: Chuck Lever chuck.lever@oracle.com
Now that I've added a file under /proc/net/rpc that is managed by the SunRPC's Kerberos mechanism, replace NFSD's supported_krb5_enctypes file with a symlink to the new SunRPC proc file, which contains exactly the same content.
Remarkably, commit b0b0c0a26e84 ("nfsd: add proc file listing kernel's gss_krb5 enctypes") added the nfsd_supported_krb5_enctypes file in 2011, but this file has never been documented in nfsd(7).
Tested-by: Scott Mayhew smayhew@redhat.com Signed-off-by: Chuck Lever chuck.lever@oracle.com --- fs/nfsd/nfsctl.c | 74 ++++++++++++++++++++++++++++++++++++++++++------------ 1 file changed, 58 insertions(+), 16 deletions(-)
diff --git a/fs/nfsd/nfsctl.c b/fs/nfsd/nfsctl.c index f2a0d6ac88df..04474b8ccf0a 100644 --- a/fs/nfsd/nfsctl.c +++ b/fs/nfsd/nfsctl.c @@ -14,7 +14,6 @@ #include <linux/lockd/lockd.h> #include <linux/sunrpc/addr.h> #include <linux/sunrpc/gss_api.h> -#include <linux/sunrpc/gss_krb5_enctypes.h> #include <linux/sunrpc/rpc_pipe_fs.h> #include <linux/module.h> #include <linux/fsnotify.h> @@ -47,7 +46,6 @@ enum { NFSD_MaxBlkSize, NFSD_MaxConnections, NFSD_Filecache, - NFSD_SupportedEnctypes, /* * The below MUST come last. Otherwise we leave a hole in nfsd_files[] * with !CONFIG_NFSD_V4 and simple_fill_super() goes oops @@ -187,16 +185,6 @@ static int export_features_show(struct seq_file *m, void *v)
DEFINE_SHOW_ATTRIBUTE(export_features);
-#if defined(CONFIG_SUNRPC_GSS) || defined(CONFIG_SUNRPC_GSS_MODULE) -static int supported_enctypes_show(struct seq_file *m, void *v) -{ - seq_printf(m, KRB5_SUPPORTED_ENCTYPES); - return 0; -} - -DEFINE_SHOW_ATTRIBUTE(supported_enctypes); -#endif /* CONFIG_SUNRPC_GSS or CONFIG_SUNRPC_GSS_MODULE */ - static const struct file_operations pool_stats_operations = { .open = nfsd_pool_stats_open, .read = seq_read, @@ -1150,6 +1138,9 @@ static struct inode *nfsd_get_inode(struct super_block *sb, umode_t mode) inode->i_op = &simple_dir_inode_operations; inc_nlink(inode); break; + case S_IFLNK: + inode->i_op = &simple_symlink_inode_operations; + break; default: break; } @@ -1195,6 +1186,59 @@ static struct dentry *nfsd_mkdir(struct dentry *parent, struct nfsdfs_client *nc goto out; }
+#if IS_ENABLED(CONFIG_SUNRPC_GSS) +static int __nfsd_symlink(struct inode *dir, struct dentry *dentry, + umode_t mode, const char *content) +{ + struct inode *inode; + + inode = nfsd_get_inode(dir->i_sb, mode); + if (!inode) + return -ENOMEM; + + inode->i_link = (char *)content; + inode->i_size = strlen(content); + + d_add(dentry, inode); + inc_nlink(dir); + fsnotify_create(dir, dentry); + return 0; +} + +/* + * @content is assumed to be a NUL-terminated string that lives + * longer than the symlink itself. + */ +static void nfsd_symlink(struct dentry *parent, const char *name, + const char *content) +{ + struct inode *dir = parent->d_inode; + struct dentry *dentry; + int ret = -ENOMEM; + + inode_lock(dir); + dentry = d_alloc_name(parent, name); + if (!dentry) + goto out_err; + ret = __nfsd_symlink(d_inode(parent), dentry, S_IFLNK | 0777, content); + if (ret) + goto out_err; +out: + inode_unlock(dir); + return; +out_err: + dput(dentry); + dentry = ERR_PTR(ret); + goto out; +} +#else +static inline void nfsd_symlink(struct dentry *parent, const char *name, + const char *content) +{ +} + +#endif + static void clear_ncl(struct inode *inode) { struct nfsdfs_client *ncl = inode->i_private; @@ -1355,10 +1399,6 @@ static int nfsd_fill_super(struct super_block *sb, struct fs_context *fc) [NFSD_MaxBlkSize] = {"max_block_size", &transaction_ops, S_IWUSR|S_IRUGO}, [NFSD_MaxConnections] = {"max_connections", &transaction_ops, S_IWUSR|S_IRUGO}, [NFSD_Filecache] = {"filecache", &nfsd_file_cache_stats_fops, S_IRUGO}, -#if defined(CONFIG_SUNRPC_GSS) || defined(CONFIG_SUNRPC_GSS_MODULE) - [NFSD_SupportedEnctypes] = {"supported_krb5_enctypes", - &supported_enctypes_fops, S_IRUGO}, -#endif /* CONFIG_SUNRPC_GSS or CONFIG_SUNRPC_GSS_MODULE */ #ifdef CONFIG_NFSD_V4 [NFSD_Leasetime] = {"nfsv4leasetime", &transaction_ops, S_IWUSR|S_IRUSR}, [NFSD_Gracetime] = {"nfsv4gracetime", &transaction_ops, S_IWUSR|S_IRUSR}, @@ -1371,6 +1411,8 @@ static int nfsd_fill_super(struct super_block *sb, struct fs_context *fc) ret = simple_fill_super(sb, 0x6e667364, nfsd_files); if (ret) return ret; + nfsd_symlink(sb->s_root, "supported_krb5_enctypes", + "/proc/net/rpc/gss_krb5_enctypes"); dentry = nfsd_mkdir(sb->s_root, NULL, "clients"); if (IS_ERR(dentry)) return PTR_ERR(dentry);