fix CVE-2024-20696

backport-CVE-2024-20696.patch

@@ -0,0 +1,119 @@
+From eac15e252010c1189a5c0f461364dbe2cd2a68b1 Mon Sep 17 00:00:00 2001
+From: "Dustin L. Howett" <dustin@howett.net>
+Date: Thu, 9 May 2024 18:59:17 -0500
+Subject: [PATCH] rar4 reader: protect copy_from_lzss_window_to_unp() (#2172)
+
+copy_from_lzss_window_to_unp unnecessarily took an `int` parameter where
+both of its callers were holding a `size_t`.
+
+A lzss opcode chain could be constructed that resulted in a negative
+copy length, which when passed into memcpy would result in a very, very
+large positive number.
+
+Switching copy_from_lzss_window_to_unp to take a `size_t` allows it to
+properly bounds-check length.
+
+In addition, this patch also ensures that `length` is not itself larger
+than the destination buffer.
+
+Security: CVE-2024-20696
+
+Reference:https://github.com/libarchive/libarchive/commit/eac15e252010c1189a5c0f461364dbe2cd2a68b1
+Conflict:copy_from_lzss_window_to_unp() -> copy_from_lzss_window();adapt context
+---
+ libarchive/archive_read_support_format_rar.c | 28 +++++++++++++-------
+ 1 file changed, 18 insertions(+), 10 deletions(-)
+
+diff --git a/libarchive/archive_read_support_format_rar.c b/libarchive/archive_read_support_format_rar.c
+index c2666b2..512f5a6 100644
+--- a/libarchive/archive_read_support_format_rar.c
++++ b/libarchive/archive_read_support_format_rar.c
+@@ -358,7 +358,7 @@ static int make_table_recurse(struct archive_read *, struct huffman_code *, int,
+                               struct huffman_table_entry *, int, int);
+ static int64_t expand(struct archive_read *, int64_t);
+ static int copy_from_lzss_window(struct archive_read *, const void **,
+-                                   int64_t, int);
++                                   int64_t, size_t);
+ static const void *rar_read_ahead(struct archive_read *, size_t, ssize_t *);
+ 
+ /*
+@@ -1936,7 +1936,7 @@ read_data_compressed(struct archive_read *a, const void **buff, size_t *size,
+         bs = rar->unp_buffer_size - rar->unp_offset;
+       else
+         bs = (size_t)rar->bytes_uncopied;
+-      ret = copy_from_lzss_window(a, buff, rar->offset, (int)bs);
++      ret = copy_from_lzss_window(a, buff, rar->offset, bs);
+       if (ret != ARCHIVE_OK)
+         return (ret);
+       rar->offset += bs;
+@@ -2065,7 +2065,7 @@ read_data_compressed(struct archive_read *a, const void **buff, size_t *size,
+       bs = rar->unp_buffer_size - rar->unp_offset;
+     else
+       bs = (size_t)rar->bytes_uncopied;
+-    ret = copy_from_lzss_window(a, buff, rar->offset, (int)bs);
++    ret = copy_from_lzss_window(a, buff, rar->offset, bs);
+     if (ret != ARCHIVE_OK)
+       return (ret);
+     rar->offset += bs;
+@@ -2923,11 +2923,16 @@ bad_data:
+ 
+ static int
+ copy_from_lzss_window(struct archive_read *a, const void **buffer,
+-                        int64_t startpos, int length)
++                        int64_t startpos, size_t length)
+ {
+   int windowoffs, firstpart;
+   struct rar *rar = (struct rar *)(a->format->data);
+ 
++  if (length > rar->unp_buffer_size)
++  {
++    goto fatal;
++  }
++
+   if (!rar->unp_buffer)
+   {
+     if ((rar->unp_buffer = malloc(rar->unp_buffer_size)) == NULL)
+@@ -2939,17 +2944,17 @@ copy_from_lzss_window(struct archive_read *a, const void **buffer,
+   }
+ 
+   windowoffs = lzss_offset_for_position(&rar->lzss, startpos);
+-  if(windowoffs + length <= lzss_size(&rar->lzss)) {
++  if(windowoffs + length <= (size_t)lzss_size(&rar->lzss)) {
+     memcpy(&rar->unp_buffer[rar->unp_offset], &rar->lzss.window[windowoffs],
+            length);
+-  } else if (length <= lzss_size(&rar->lzss)) {
++  } else if (length <= (size_t)lzss_size(&rar->lzss)) {
+     firstpart = lzss_size(&rar->lzss) - windowoffs;
+     if (firstpart < 0) {
+       archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
+                         "Bad RAR file data");
+       return (ARCHIVE_FATAL);
+     }
+-    if (firstpart < length) {
++    if ((size_t)firstpart < length) {
+       memcpy(&rar->unp_buffer[rar->unp_offset],
+              &rar->lzss.window[windowoffs], firstpart);
+       memcpy(&rar->unp_buffer[rar->unp_offset + firstpart],
+@@ -2959,9 +2964,7 @@ copy_from_lzss_window(struct archive_read *a, const void **buffer,
+              &rar->lzss.window[windowoffs], length);
+     }
+   } else {
+-      archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
+-                        "Bad RAR file data");
+-      return (ARCHIVE_FATAL);
++      goto fatal;
+   }
+   rar->unp_offset += length;
+   if (rar->unp_offset >= rar->unp_buffer_size)
+@@ -2969,6 +2972,11 @@ copy_from_lzss_window(struct archive_read *a, const void **buffer,
+   else
+     *buffer = NULL;
+   return (ARCHIVE_OK);
++
++fatal:
++  archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
++                    "Bad RAR file data");
++  return (ARCHIVE_FATAL);
+ }
+ 
+ static const void *

libarchive.spec

@@ -2,7 +2,7 @@
 
 Name:           libarchive
 Version:        3.5.2
-Release:        6
+Release:        7
 Summary:        Multi-format archive and compression library
 
 License:        BSD
@@ -19,6 +19,7 @@ Patch6002:	backport-0002-CVE-2021-36976.patch
 Patch6003:	backport-CVE-2021-31566.patch
 Patch6004:	backport-CVE-2022-26280.patch
 Patch6005:	backport-CVE-2022-36227.patch
+Patch6006:	backport-CVE-2024-20696.patch
 
 Patch9000:	libarchive-uninitialized-value.patch
 
@@ -193,6 +194,12 @@ run_testsuite
 %{_bindir}/bsdcat
 
 %changelog
+* Thu Jun 06 2024 lingsheng <lingsheng1@h-partners.com> - 3.5.2-7
+- Type:CVE
+- ID:CVE-2024-20696
+- SUG:NA
+- DESC:fix CVE-2024-20696
+
 * Thu Mar 02 2023 zhangpan <zhangpan103@h-paetners.com> - 3.5.2-6
 - fix CVE-2021-36976 patch