From 4e575be32d0d128fa046ca74353d1ac880436948 Mon Sep 17 00:00:00 2001
From: lutianxiong <lutianxiong@huawei.com>
Date: Thu, 20 Aug 2020 19:09:03 +0800
Subject: [PATCH] Add a loop checker in read_data_compressed to avoid stack
 overflow.

Signed-off-by: lutianxiong <lutianxiong@huawei.com>
---
 libarchive/archive_read_support_format_rar.c | 14 ++++++++++----
 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/libarchive/archive_read_support_format_rar.c b/libarchive/archive_read_support_format_rar.c
index 98efbb1a6..283a96044 100644
--- a/libarchive/archive_read_support_format_rar.c
+++ b/libarchive/archive_read_support_format_rar.c
@@ -151,6 +151,9 @@
 #undef minimum
 #define minimum(a, b)	((a)<(b)?(a):(b))
 
+/* Stack overflow check */
+#define MAX_COMPRESS_DEPTH 1024
+
 /* Fields common to all headers */
 struct rar_header
 {
@@ -340,7 +343,7 @@ static int read_symlink_stored(struct archive_read *, struct archive_entry *,
 static int read_data_stored(struct archive_read *, const void **, size_t *,
                             int64_t *);
 static int read_data_compressed(struct archive_read *, const void **, size_t *,
-                          int64_t *);
+                          int64_t *, size_t);
 static int rar_br_preparation(struct archive_read *, struct rar_br *);
 static int parse_codes(struct archive_read *);
 static void free_codes(struct archive_read *);
@@ -1026,7 +1029,7 @@ archive_read_format_rar_read_data(struct archive_read *a, const void **buff,
   case COMPRESS_METHOD_NORMAL:
   case COMPRESS_METHOD_GOOD:
   case COMPRESS_METHOD_BEST:
-    ret = read_data_compressed(a, buff, size, offset);
+    ret = read_data_compressed(a, buff, size, offset, 0);
     if (ret != ARCHIVE_OK && ret != ARCHIVE_WARN) {
       __archive_ppmd7_functions.Ppmd7_Free(&rar->ppmd7_context);
       rar->start_new_table = 1;
@@ -1883,8 +1886,11 @@ read_data_stored(struct archive_read *a, const void **buff, size_t *size,
 
 static int
 read_data_compressed(struct archive_read *a, const void **buff, size_t *size,
-               int64_t *offset)
+               int64_t *offset, size_t looper)
 {
+  if (looper++ > MAX_COMPRESS_DEPTH)
+    return (ARCHIVE_FATAL);
+
   struct rar *rar;
   int64_t start, end, actualend;
   size_t bs;
@@ -1982,7 +1988,7 @@ read_data_compressed(struct archive_read *a, const void **buff, size_t *size,
         {
           case 0:
             rar->start_new_table = 1;
-            return read_data_compressed(a, buff, size, offset);
+            return read_data_compressed(a, buff, size, offset, looper);
 
           case 2:
             rar->ppmd_eod = 1;/* End Of ppmd Data. */
