[Buildroot] [git commit branch/2019.02.x] package/libarchive: add upstream security fix for CVE-2019-18408

[Peter Korsgaard]

commit: https://git.buildroot.net/buildroot/commit/?id=e07076c926bc55e74e359a0a337fcd72ce015015
branch: https://git.buildroot.net/buildroot/commit/?id=refs/heads/2019.02.x

Fixes the following security issue:

- CVE-2019-18408: archive_read_format_rar_read_data in
  archive_read_support_format_rar.c in libarchive before 3.4.0 has a
  use-after-free in a certain ARCHIVE_FAILED situation, related to
  Ppmd7_DecodeSymbol.

Signed-off-by: Peter Korsgaard <peter at korsgaard.com>
---
 .../0007-RAR-reader-fix-use-after-free.patch       | 36 ++++++++++++++++++++++
 1 file changed, 36 insertions(+)

diff --git a/package/libarchive/0007-RAR-reader-fix-use-after-free.patch b/package/libarchive/0007-RAR-reader-fix-use-after-free.patch
new file mode 100644
index 0000000000..5acbb77e96
--- /dev/null
+++ b/package/libarchive/0007-RAR-reader-fix-use-after-free.patch
@@ -0,0 +1,36 @@
+From b8592ecba2f9e451e1f5cb7ab6dcee8b8e7b3f60 Mon Sep 17 00:00:00 2001
+From: Martin Matuska <martin at matuska.org>
+Date: Sat, 11 May 2019 02:36:53 +0200
+Subject: [PATCH] RAR reader: fix use after free
+
+If read_data_compressed() returns ARCHIVE_FAILED, the caller is allowed
+to continue with next archive headers. We need to set rar->start_new_table
+after the ppmd7_context got freed, otherwise it won't be allocated again.
+
+Reported by: OSS-Fuzz issue 2582
+
+[Peter: fixes CVE-2019-18408]
+Signed-off-by: Peter Korsgaard <peter at korsgaard.com>
+---
+ libarchive/archive_read_support_format_rar.c | 4 +++-
+ 1 file changed, 3 insertions(+), 1 deletion(-)
+
+diff --git a/libarchive/archive_read_support_format_rar.c b/libarchive/archive_read_support_format_rar.c
+index a8cc5c94..49360876 100644
+--- a/libarchive/archive_read_support_format_rar.c
++++ b/libarchive/archive_read_support_format_rar.c
+@@ -1024,8 +1024,10 @@ archive_read_format_rar_read_data(struct archive_read *a, const void **buff,
+   case COMPRESS_METHOD_GOOD:
+   case COMPRESS_METHOD_BEST:
+     ret = read_data_compressed(a, buff, size, offset);
+-    if (ret != ARCHIVE_OK && ret != ARCHIVE_WARN)
++    if (ret != ARCHIVE_OK && ret != ARCHIVE_WARN) {
+       __archive_ppmd7_functions.Ppmd7_Free(&rar->ppmd7_context);
++      rar->start_new_table = 1;
++    }
+     break;
+ 
+   default:
+-- 
+2.20.1
+