[PATCH 24/24] devpts: handle fsid mappings

[Christian Brauner]

When a uid or gid mount option is specified with devpts have it lookup the
corresponding kfsids in the fsid mappings. If no fsid mappings are setup the
behavior is unchanged, i.e. fsids are looked up in the id mappings.

Signed-off-by: Christian Brauner <christian.brauner at ubuntu.com>
---
 fs/devpts/inode.c | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index 42e5a766d33c..139958892572 100644
--- a/fs/devpts/inode.c
+++ b/fs/devpts/inode.c
@@ -24,6 +24,7 @@
 #include <linux/parser.h>
 #include <linux/fsnotify.h>
 #include <linux/seq_file.h>
+#include <linux/fsuidgid.h>
 
 #define DEVPTS_DEFAULT_MODE 0600
 /*
@@ -277,7 +278,7 @@ static int parse_mount_options(char *data, int op, struct pts_mount_opts *opts)
 		case Opt_uid:
 			if (match_int(&args[0], &option))
 				return -EINVAL;
-			uid = make_kuid(current_user_ns(), option);
+			uid = make_kfsuid(current_user_ns(), option);
 			if (!uid_valid(uid))
 				return -EINVAL;
 			opts->uid = uid;
@@ -286,7 +287,7 @@ static int parse_mount_options(char *data, int op, struct pts_mount_opts *opts)
 		case Opt_gid:
 			if (match_int(&args[0], &option))
 				return -EINVAL;
-			gid = make_kgid(current_user_ns(), option);
+			gid = make_kfsgid(current_user_ns(), option);
 			if (!gid_valid(gid))
 				return -EINVAL;
 			opts->gid = gid;
@@ -410,7 +411,7 @@ static int devpts_show_options(struct seq_file *seq, struct dentry *root)
 			   from_kuid_munged(&init_user_ns, opts->uid));
 	if (opts->setgid)
 		seq_printf(seq, ",gid=%u",
-			   from_kgid_munged(&init_user_ns, opts->gid));
+			   from_kfsgid_munged(&init_user_ns, opts->gid));
 	seq_printf(seq, ",mode=%03o", opts->mode);
 	seq_printf(seq, ",ptmxmode=%03o", opts->ptmxmode);
 	if (opts->max < NR_UNIX98_PTY_MAX)
-- 
2.25.0