[SECURITY PATCH 023/117] gnulib/regexec: Resolve unused variable

[Daniel Kiper]

From: Darren Kenny <darren.kenny@oracle.com>

This is a really minor issue where a variable is being assigned to but
not checked before it is overwritten again.

The reason for this issue is that we are not building with DEBUG set and
this in turn means that the assert() that reads the value of the
variable match_last is being processed out.

The solution, move the assignment to match_last in to an ifdef DEBUG too.

Fixes: CID 292459

Signed-off-by: Darren Kenny <darren.kenny@oracle.com>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
---
 bootstrap.conf                                      |  2 +-
 conf/Makefile.extra-dist                            |  1 +
 grub-core/lib/gnulib-patches/fix-unused-value.patch | 14 ++++++++++++++
 3 files changed, 16 insertions(+), 1 deletion(-)
 create mode 100644 grub-core/lib/gnulib-patches/fix-unused-value.patch

diff --git a/bootstrap.conf b/bootstrap.conf
index 6d383240e..4c8c37c16 100644
--- a/bootstrap.conf
+++ b/bootstrap.conf
@@ -79,7 +79,7 @@ cp -a INSTALL INSTALL.grub
 
 bootstrap_post_import_hook () {
   set -e
-  for patchname in fix-base64 fix-null-deref fix-width no-abort; do
+  for patchname in fix-base64 fix-null-deref fix-unused-value fix-width 
no-abort; do
     patch -d grub-core/lib/gnulib -p2 \
       < "grub-core/lib/gnulib-patches/$patchname.patch"
   done
diff --git a/conf/Makefile.extra-dist b/conf/Makefile.extra-dist
index 37dc3aa10..0d3b74e8e 100644
--- a/conf/Makefile.extra-dist
+++ b/conf/Makefile.extra-dist
@@ -30,6 +30,7 @@ EXTRA_DIST += grub-core/genemuinitheader.sh
 
 EXTRA_DIST += grub-core/lib/gnulib-patches/fix-base64.patch
 EXTRA_DIST += grub-core/lib/gnulib-patches/fix-null-deref.patch
+EXTRA_DIST += grub-core/lib/gnulib-patches/fix-unused-value.patch
 EXTRA_DIST += grub-core/lib/gnulib-patches/fix-width.patch
 EXTRA_DIST += grub-core/lib/gnulib-patches/no-abort.patch
 
diff --git a/grub-core/lib/gnulib-patches/fix-unused-value.patch 
b/grub-core/lib/gnulib-patches/fix-unused-value.patch
new file mode 100644
index 000000000..ba51f1bf2
--- /dev/null
+++ b/grub-core/lib/gnulib-patches/fix-unused-value.patch
@@ -0,0 +1,14 @@
+--- a/lib/regexec.c    2020-10-21 14:25:35.310195912 +0000
++++ b/lib/regexec.c    2020-10-21 14:32:07.961765604 +0000
+@@ -828,7 +828,11 @@
+                   break;
+                 if (__glibc_unlikely (err != REG_NOMATCH))
+                   goto free_return;
++#ifdef DEBUG
++                /* Only used for assertion below when DEBUG is set, otherwise
++                   it will be over-written when we loop around.  */
+                 match_last = -1;
++#endif
+               }
+             else
+               break; /* We found a match.  */
-- 
2.11.0