1 files changed, 43 insertions, 6 deletions

diff --git a/net/9p/protocol.c b/net/9p/protocol.c
index 3d33ecf13327..ab9127ec5b7a 100644
--- a/net/9p/protocol.c
+++ b/net/9p/protocol.c
@@ -85,6 +85,8 @@ pdu_write_u(struct p9_fcall *pdu, const char __user *udata, size_t size)
         d - int32_t
         q - int64_t
         s - string
+        u - numeric uid
+        g - numeric gid
         S - stat
         Q - qid
         D - data blob (int32_t size followed by void *, results are not freed)
@@ -163,6 +165,26 @@ p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt,
                                         (*sptr)[len] = 0;
                         }
                         break;
+                case 'u': {
+                                kuid_t *uid = va_arg(ap, kuid_t *);
+                                __le32 le_val;
+                                if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+                                        errcode = -EFAULT;
+                                        break;
+                                }
+                                *uid = make_kuid(&init_user_ns,
+                                                 le32_to_cpu(le_val));
+                        } break;
+                case 'g': {
+                                kgid_t *gid = va_arg(ap, kgid_t *);
+                                __le32 le_val;
+                                if (pdu_read(pdu, &le_val, sizeof(le_val))) {
+                                        errcode = -EFAULT;
+                                        break;
+                                }
+                                *gid = make_kgid(&init_user_ns,
+                                                 le32_to_cpu(le_val));
+                        } break;
                 case 'Q':{
                                 struct p9_qid *qid =
                                     va_arg(ap, struct p9_qid *);
@@ -177,11 +199,12 @@ p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt,
                                     va_arg(ap, struct p9_wstat *);
 
                                 memset(stbuf, 0, sizeof(struct p9_wstat));
-                                stbuf->n_uid = stbuf->n_gid = stbuf->n_muid =
-                                                                        -1;
+                                stbuf->n_uid = stbuf->n_muid = INVALID_UID;
+                                stbuf->n_gid = INVALID_GID;
+
                                 errcode =
                                     p9pdu_readf(pdu, proto_version,
-                                                "wwdQdddqssss?sddd",
+                                                "wwdQdddqssss?sugu",
                                                 &stbuf->size, &stbuf->type,
                                                 &stbuf->dev, &stbuf->qid,
                                                 &stbuf->mode, &stbuf->atime,
@@ -294,7 +317,7 @@ p9pdu_vreadf(struct p9_fcall *pdu, int proto_version, const char *fmt,
                                 memset(stbuf, 0, sizeof(struct p9_stat_dotl));
                                 errcode =
                                     p9pdu_readf(pdu, proto_version,
-                                        "qQdddqqqqqqqqqqqqqqq",
+                                        "qQdugqqqqqqqqqqqqqqq",
                                         &stbuf->st_result_mask,
                                         &stbuf->qid,
                                         &stbuf->st_mode,
@@ -377,6 +400,20 @@ p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
                                         errcode = -EFAULT;
                         }
                         break;
+                case 'u': {
+                                kuid_t uid = va_arg(ap, kuid_t);
+                                __le32 val = cpu_to_le32(
+                                                from_kuid(&init_user_ns, uid));
+                                if (pdu_write(pdu, &val, sizeof(val)))
+                                        errcode = -EFAULT;
+                        } break;
+                case 'g': {
+                                kgid_t gid = va_arg(ap, kgid_t);
+                                __le32 val = cpu_to_le32(
+                                                from_kgid(&init_user_ns, gid));
+                                if (pdu_write(pdu, &val, sizeof(val)))
+                                        errcode = -EFAULT;
+                        } break;
                 case 'Q':{
                                 const struct p9_qid *qid =
                                     va_arg(ap, const struct p9_qid *);
@@ -390,7 +427,7 @@ p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
                                     va_arg(ap, const struct p9_wstat *);
                                 errcode =
                                     p9pdu_writef(pdu, proto_version,
-                                                 "wwdQdddqssss?sddd",
+                                                 "wwdQdddqssss?sugu",
                                                  stbuf->size, stbuf->type,
                                                  stbuf->dev, &stbuf->qid,
                                                  stbuf->mode, stbuf->atime,
@@ -468,7 +505,7 @@ p9pdu_vwritef(struct p9_fcall *pdu, int proto_version, const char *fmt,
                                                         struct p9_iattr_dotl *);
 
                                 errcode = p9pdu_writef(pdu, proto_version,
-                                                        "ddddqqqqq",
+                                                        "ddugqqqqq",
                                                         p9attr->valid,
                                                         p9attr->mode,
                                                         p9attr->uid,