[PATCH] devpts: allow mounting with uid/gid of uint32_t

From: Dongsu Park
Date: Tue Aug 18 2015 - 10:31:12 EST


To allow devpts to be mounted with options of uid/gid of uint32_t,
use kstrtouint() instead of match_int(). Doing that, mounting devpts
with uid or gid > (2^31 - 1) will work as expected, e.g.:

# mount -t devpts devpts /tmp/devptsdir -o \
newinstance,ptmxmode=0666,mode=620,uid=3598450688,gid=3598450693

It was originally by reported on systemd github issues:
https://github.com/systemd/systemd/issues/956

Reported-by: Alban Crequy <alban@xxxxxxxxxxxx>
Signed-off-by: Dongsu Park <dpark@xxxxxxxxxx>
---
fs/devpts/inode.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/fs/devpts/inode.c b/fs/devpts/inode.c
index c35ffdc12bba..83c3e7368f38 100644
--- a/fs/devpts/inode.c
+++ b/fs/devpts/inode.c
@@ -188,23 +188,33 @@ static int parse_mount_options(char *data, int op, struct pts_mount_opts *opts)
token = match_token(p, tokens, args);
switch (token) {
case Opt_uid:
- if (match_int(&args[0], &option))
+ {
+ char *uidstr = args[0].from;
+ uid_t uidval;
+ int rc = kstrtouint(uidstr, 0, &uidval);
+ if (rc)
return -EINVAL;
- uid = make_kuid(current_user_ns(), option);
+ uid = make_kuid(current_user_ns(), uidval);
if (!uid_valid(uid))
return -EINVAL;
opts->uid = uid;
opts->setuid = 1;
break;
+ }
case Opt_gid:
- if (match_int(&args[0], &option))
+ {
+ char *gidstr = args[0].from;
+ gid_t gidval;
+ int rc = kstrtouint(gidstr, 0, &gidval);
+ if (rc)
return -EINVAL;
- gid = make_kgid(current_user_ns(), option);
+ gid = make_kgid(current_user_ns(), gidval);
if (!gid_valid(gid))
return -EINVAL;
opts->gid = gid;
opts->setgid = 1;
break;
+ }
case Opt_mode:
if (match_octal(&args[0], &option))
return -EINVAL;
--
2.1.0

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