From: Daniel Rosenberg <drosen@google.com>
Date: Mon, 13 Mar 2017 22:34:03 +0000 (-0700)
Subject: ANDROID: sdcardfs: Fix gid issue
X-Git-Tag: release-20171130_firefly~4^2~100^2~197
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=1d2509402f0531a082c81e963372d5d8e3368190;p=firefly-linux-kernel-4.4.55.git

ANDROID: sdcardfs: Fix gid issue

We were already calculating most of these values,
and erroring out because the check was confused by this.
Instead of recalculating, adjust it as needed.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Bug: 36160015
Change-Id: I9caf3e2fd32ca2e37ff8ed71b1d392f1761bc9a9
---

diff --git a/fs/sdcardfs/derived_perm.c b/fs/sdcardfs/derived_perm.c
index 763f10340487..28e9b8d42f9e 100644
--- a/fs/sdcardfs/derived_perm.c
+++ b/fs/sdcardfs/derived_perm.c
@@ -205,13 +205,13 @@ void fixup_lower_ownership(struct dentry* dentry, const char *name) {
 			break;
 		case PERM_ANDROID_PACKAGE:
 			if (info->d_uid != 0)
-				gid = multiuser_get_ext_gid(info->userid, info->d_uid);
+				gid = multiuser_get_ext_gid(info->d_uid);
 			else
 				gid = multiuser_get_uid(info->userid, uid);
 			break;
 		case PERM_ANDROID_PACKAGE_CACHE:
 			if (info->d_uid != 0)
-				gid = multiuser_get_cache_gid(info->userid, info->d_uid);
+				gid = multiuser_get_cache_gid(info->d_uid);
 			else
 				gid = multiuser_get_uid(info->userid, uid);
 			break;
diff --git a/fs/sdcardfs/multiuser.h b/fs/sdcardfs/multiuser.h
index ca141ff40b49..2e89b5872314 100644
--- a/fs/sdcardfs/multiuser.h
+++ b/fs/sdcardfs/multiuser.h
@@ -28,22 +28,17 @@
 typedef uid_t userid_t;
 typedef uid_t appid_t;
 
-static inline uid_t multiuser_get_uid(userid_t user_id, appid_t app_id) {
+static inline uid_t multiuser_get_uid(userid_t user_id, appid_t app_id)
+{
 	return (user_id * AID_USER_OFFSET) + (app_id % AID_USER_OFFSET);
 }
 
-static inline gid_t multiuser_get_cache_gid(userid_t user_id, appid_t app_id) {
-	if (app_id >= AID_APP_START && app_id <= AID_APP_END) {
-		return multiuser_get_uid(user_id, (app_id - AID_APP_START) + AID_CACHE_GID_START);
-	} else {
-		return -1;
-	}
+static inline gid_t multiuser_get_cache_gid(uid_t uid)
+{
+	return uid - AID_APP_START + AID_CACHE_GID_START;
 }
 
-static inline gid_t multiuser_get_ext_gid(userid_t user_id, appid_t app_id) {
-	if (app_id >= AID_APP_START && app_id <= AID_APP_END) {
-		return multiuser_get_uid(user_id, (app_id - AID_APP_START) + AID_EXT_GID_START);
-	} else {
-		return -1;
-	}
+static inline gid_t multiuser_get_ext_gid(uid_t uid)
+{
+	return uid - AID_APP_START + AID_EXT_GID_START;
 }