X-Git-Url: http://git.osdn.net/view?a=blobdiff_plain;f=fs%2Fxattr.c;h=cd786d53c611d5c4e25f8c858e38c6e376f3417e;hb=b1c1c6b2c29151718f818877e5978de972cc302e;hp=7444fb1b348455d1ef0e3f26805f3b6d82b21fa9;hpb=7411c392ab8137f376a2f3a9f292ff7eb910bcfb;p=sagit-ice-cold%2Fkernel_xiaomi_msm8998.git

diff --git a/fs/xattr.c b/fs/xattr.c
index 7444fb1b3484..cd786d53c611 100644
--- a/fs/xattr.c
+++ b/fs/xattr.c
@@ -430,6 +430,7 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
 	void *kvalue = NULL;
 	void *vvalue = NULL;
 	char kname[XATTR_NAME_MAX + 1];
+	char kvalue_onstack[SZ_4K] __aligned(sizeof(long));
 
 	error = strncpy_from_user(kname, name, sizeof(kname));
 	if (error == 0 || error == sizeof(kname))
@@ -438,14 +439,19 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
 		return error;
 
 	if (size) {
-		if (size > XATTR_SIZE_MAX)
-			size = XATTR_SIZE_MAX;
-		kvalue = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
-		if (!kvalue) {
-			vvalue = vzalloc(size);
-			if (!vvalue)
-				return -ENOMEM;
-			kvalue = vvalue;
+		if (size <= ARRAY_SIZE(kvalue_onstack)) {
+			kvalue = kvalue_onstack;
+			memset(kvalue, 0, size);
+		} else {
+			if (size > XATTR_SIZE_MAX)
+				size = XATTR_SIZE_MAX;
+			kvalue = kzalloc(size, GFP_KERNEL | __GFP_NOWARN);
+			if (!kvalue) {
+				vvalue = vzalloc(size);
+				if (!vvalue)
+					return -ENOMEM;
+				kvalue = vvalue;
+			}
 		}
 	}
 
@@ -463,7 +469,7 @@ getxattr(struct dentry *d, const char __user *name, void __user *value,
 	}
 	if (vvalue)
 		vfree(vvalue);
-	else
+	else if (kvalue != kvalue_onstack)
 		kfree(kvalue);
 	return error;
 }