X-Git-Url: http://git.openwrt.org/?a=blobdiff_plain;f=target%2Flinux%2Fbrcm2708%2Fpatches-4.19%2F950-0687-Limit-max_req_size-under-arm64-or-any-other-platform.patch;fp=target%2Flinux%2Fbrcm2708%2Fpatches-4.19%2F950-0687-Limit-max_req_size-under-arm64-or-any-other-platform.patch;h=87b4e9b58af75f4feb9bcadb7813119a63885a8c;hb=84d555aa74434392b682fd9eb0fa701c89a046d6;hp=0000000000000000000000000000000000000000;hpb=953973c2991e8640549a55df7a0574a1abac8644;p=openwrt%2Fstaging%2Fchunkeey.git

diff --git a/target/linux/brcm2708/patches-4.19/950-0687-Limit-max_req_size-under-arm64-or-any-other-platform.patch b/target/linux/brcm2708/patches-4.19/950-0687-Limit-max_req_size-under-arm64-or-any-other-platform.patch
new file mode 100644
index 0000000000..87b4e9b58a
--- /dev/null
+++ b/target/linux/brcm2708/patches-4.19/950-0687-Limit-max_req_size-under-arm64-or-any-other-platform.patch
@@ -0,0 +1,33 @@
+From 7bfcb31431f06efc233e4cc4d7ab65e10a6522cd Mon Sep 17 00:00:00 2001
+From: Yaroslav Rosomakho <yaroslavros@gmail.com>
+Date: Fri, 23 Aug 2019 11:02:22 +0200
+Subject: [PATCH] Limit max_req_size under arm64 (or any other platform
+ that uses swiotlb) to prevent potential buffer overflow due to bouncing.
+
+Signed-off-by: Yaroslav Rosomakho <yaroslavros@gmail.com>
+---
+ drivers/mmc/host/bcm2835-mmc.c | 6 +++++-
+ 1 file changed, 5 insertions(+), 1 deletion(-)
+
+--- a/drivers/mmc/host/bcm2835-mmc.c
++++ b/drivers/mmc/host/bcm2835-mmc.c
+@@ -38,6 +38,7 @@
+ #include <linux/dmaengine.h>
+ #include <linux/dma-mapping.h>
+ #include <linux/of_dma.h>
++#include <linux/swiotlb.h>
+ 
+ #include "sdhci.h"
+ 
+@@ -1374,7 +1375,10 @@ static int bcm2835_mmc_add_host(struct b
+ 	}
+ #endif
+ 	mmc->max_segs = 128;
+-	mmc->max_req_size = 524288;
++	if (swiotlb_max_segment())
++		mmc->max_req_size = (1 << IO_TLB_SHIFT) * IO_TLB_SEGSIZE;
++	else
++		mmc->max_req_size = 524288;
+ 	mmc->max_seg_size = mmc->max_req_size;
+ 	mmc->max_blk_size = 512;
+ 	mmc->max_blk_count =  65535;