Include upstream fix for bug 1985561

From a comment on the bug:
This is a regression caused by rewriting the duplicate checking code
to be more aggressive when looking for duplicates when using tail-end
packing.  In particular a file doesn't now have to be the same size
to be considered a (partial) duplicate.

fix-sparse.patch

@@ -0,0 +1,30 @@
+diff --git a/squashfs-tools/mksquashfs.c b/squashfs-tools/mksquashfs.c
+index aaa4b002bd87..127df00fb789 100644
+--- a/squashfs-tools/mksquashfs.c
++++ b/squashfs-tools/mksquashfs.c
+@@ -2190,10 +2190,23 @@ static struct file_info *duplicate(int *dupf, int *block_dup, long long file_siz
+ 			/* Yes, the block list matches.  We can use this, rather
+ 			 * than writing an identical block list.
+ 			 * If both it and us doesn't have a tail-end fragment, then we're
+-			 * finished.  Return the duplicate */
++			 * finished.  Return the duplicate.
++			 *
++			 * We have to deal with the special case where the
++			 * last block is a sparse block.  This means the
++			 * file will have matched, but, it may be a different
++			 * file length (because a tail-end sparse block may be
++			 * anything from 1 byte to block_size - 1 in size, but
++			 * stored as zero).  We can still use the block list in
++			 * this case, but, we must return a new entry with the
++			 * correct file size */
+ 			if(!frag_bytes && !dupl_ptr->fragment->size) {
+ 				*dupf = *block_dup = TRUE;
+-				return dupl_ptr;
++				if(file_size == dupl_ptr->file_size)
++					return dupl_ptr;
++				else
++					return create_non_dup(file_size, bytes, blocks, sparse, dupl_ptr->block_list,
++						dupl_ptr->start, dupl_ptr->fragment, checksum, 0, checksum_flag, FALSE);
+ 			}
+ 
+ 			/* We've got a tail-end fragment, and this file most likely

squashfs-tools.spec

@@ -2,7 +2,7 @@ Summary: Utility for the creation of squashfs filesystems
 %global forgeurl https://github.com/plougher/squashfs-tools
 Version: 4.5
 Name: squashfs-tools
-Release: 1%{?dist}
+Release: 2%{?dist}
 License: GPLv2+
 URL: %{forgeurl}/archive/4.5.tar.gz
 Source: 4.5.tar.gz
@@ -11,6 +11,10 @@ Source: 4.5.tar.gz
 # Man pages still need a lot of changes for 4.5
 Source1: mksquashfs.1
 Source2: unsquashfs.1
+# Mksquashfs: fix duplicate check when last file block is sparse
+# git diff 19b161c1cd3e31f7a396ea92dea4390ad43f27b9^ 19b161c1cd3e31f7a396ea92dea4390ad43f27b9 > fix-sparse.patch
+# https://bugzilla.gnome.org/show_bug.cgi?id=1985561
+Patch0: fix-sparse.patch
 
 BuildRequires: make
 BuildRequires:  gcc
@@ -27,6 +31,7 @@ contains the utilities for manipulating squashfs filesystems.
 
 %prep
 %setup -n %{name}-4.5
+%patch0 -p1
 
 %build
 %set_build_flags
@@ -54,6 +59,9 @@ ln -s unsquashfs %{buildroot}%{_sbindir}/sqfscat
 %{_sbindir}/sqfscat
 
 %changelog
+* Mon Jul 26 2021 Bruno Wolff III <bruno@wolff.to> - 4.5-2
+- Fix for sparse fragment bug 1985561
+
 * Fri Jul 23 2021 Bruno Wolff III <bruno@wolff.to> - 4.5-1
 - First crack at 4.5 release
 - Man pages still need significant work