From eeeb201e700dfe592c352cf92077095e2a539b89 Mon Sep 17 00:00:00 2001
From: Sean Purcell <me@seanp.xyz>
Date: Thu, 27 Apr 2017 16:54:05 -0700
Subject: [PATCH] Fix case where pages run out before end of stream

---
 .../linux-kernel/fs/squashfs/zstd_wrapper.c   | 13 ++++++------
 contrib/linux-kernel/squashfs.diff            | 21 ++++++++++---------
 2 files changed, 18 insertions(+), 16 deletions(-)

diff --git a/contrib/linux-kernel/fs/squashfs/zstd_wrapper.c b/contrib/linux-kernel/fs/squashfs/zstd_wrapper.c
index 81f4b5a4..af72c7b2 100644
--- a/contrib/linux-kernel/fs/squashfs/zstd_wrapper.c
+++ b/contrib/linux-kernel/fs/squashfs/zstd_wrapper.c
@@ -101,12 +101,13 @@ static int zstd_uncompress(struct squashfs_sb_info *msblk, void *strm,
 
 		if (out_buf.pos == out_buf.size) {
 			out_buf.dst = squashfs_next_page(output);
-			out_buf.pos = 0;
-			if (out_buf.dst != NULL) {
-				out_buf.size = PAGE_SIZE;
-			} else {
-				out_buf.size = 0;
+			if (out_buf.dst == NULL) {
+				/* shouldn't run out of pages before stream is
+				 * done */
+				goto out;
 			}
+			out_buf.pos = 0;
+			out_buf.size = PAGE_SIZE;
 		}
 
 		total_out -= out_buf.pos;
@@ -127,7 +128,7 @@ static int zstd_uncompress(struct squashfs_sb_info *msblk, void *strm,
 	if (k < b)
 		goto out;
 
-	return total_out;
+	return (int)total_out;
 
 out:
 	for (; k < b; k++)
diff --git a/contrib/linux-kernel/squashfs.diff b/contrib/linux-kernel/squashfs.diff
index e1e1235f..e3b9e855 100644
--- a/contrib/linux-kernel/squashfs.diff
+++ b/contrib/linux-kernel/squashfs.diff
@@ -1,6 +1,6 @@
-commit 7289653483a0579c3b63a06abf008210c8cc6c8b
+commit 47ba72b36506f91c3774c0bb1fa3c7a5dcfe3ea1
 Author: Sean Purcell <me@seanp.xyz>
-Date:   Thu Apr 27 14:56:25 2017 -0700
+Date:   Thu Apr 27 16:50:53 2017 -0700
 
     Add zstd support to kernel squashfs
 
@@ -90,10 +90,10 @@ index 506f4ba..24d12fd 100644
  	__le32			s_magic;
 diff --git a/fs/squashfs/zstd_wrapper.c b/fs/squashfs/zstd_wrapper.c
 new file mode 100644
-index 0000000..81f4b5a
+index 0000000..af72c7b
 --- /dev/null
 +++ b/fs/squashfs/zstd_wrapper.c
-@@ -0,0 +1,146 @@
+@@ -0,0 +1,147 @@
 +/*
 + * Squashfs - a compressed read only filesystem for Linux
 + *
@@ -197,12 +197,13 @@ index 0000000..81f4b5a
 +
 +		if (out_buf.pos == out_buf.size) {
 +			out_buf.dst = squashfs_next_page(output);
-+			out_buf.pos = 0;
-+			if (out_buf.dst != NULL) {
-+				out_buf.size = PAGE_SIZE;
-+			} else {
-+				out_buf.size = 0;
++			if (out_buf.dst == NULL) {
++				/* shouldn't run out of pages before stream is
++				 * done */
++				goto out;
 +			}
++			out_buf.pos = 0;
++			out_buf.size = PAGE_SIZE;
 +		}
 +
 +		total_out -= out_buf.pos;
@@ -223,7 +224,7 @@ index 0000000..81f4b5a
 +	if (k < b)
 +		goto out;
 +
-+	return total_out;
++	return (int)total_out;
 +
 +out:
 +	for (; k < b; k++)