From: Cong Wang <xiyou.wangcong@gmail.com>
Date: Fri, 29 Jan 2016 19:24:24 +0000 (-0800)
Subject: NFC: Use GFP_USER for user-controlled kmalloc
X-Git-Tag: v4.6-rc1~91^2~64^2~4
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=81ca7835f2cb0c3ba4236e3bcf31d997c6f5d71a;p=platform%2Fkernel%2Flinux-exynos.git

NFC: Use GFP_USER for user-controlled kmalloc

These two functions are called in sendmsg path, and the
'len' is passed from user-space, so we should not allow
malicious users to OOM kernel on purpose.

Reported-by: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Julian Calaby <julian.calaby@gmail.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
---

diff --git a/net/nfc/llcp_commands.c b/net/nfc/llcp_commands.c
index 3621a90..3425532 100644
--- a/net/nfc/llcp_commands.c
+++ b/net/nfc/llcp_commands.c
@@ -663,7 +663,7 @@ int nfc_llcp_send_i_frame(struct nfc_llcp_sock *sock,
 		return -ENOBUFS;
 	}
 
-	msg_data = kzalloc(len, GFP_KERNEL);
+	msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
 	if (msg_data == NULL)
 		return -ENOMEM;
 
@@ -729,7 +729,7 @@ int nfc_llcp_send_ui_frame(struct nfc_llcp_sock *sock, u8 ssap, u8 dsap,
 	if (local == NULL)
 		return -ENODEV;
 
-	msg_data = kzalloc(len, GFP_KERNEL);
+	msg_data = kmalloc(len, GFP_USER | __GFP_NOWARN);
 	if (msg_data == NULL)
 		return -ENOMEM;