From 8f2e60d14179df62e2c78eaeffd08bdc27e4f2c6 Mon Sep 17 00:00:00 2001 From: Lukas Javorsky Date: Thu, 6 Jun 2024 09:05:07 +0000 Subject: [PATCH] Fix for CVE-2024-20696 Resolves: RHEL-40042 --- ...ect-copy_from_lzss_window_to_unp-217.patch | 119 ++++++++++++++++++ libarchive.spec | 10 +- 2 files changed, 128 insertions(+), 1 deletion(-) create mode 100644 0004-rar4-reader-protect-copy_from_lzss_window_to_unp-217.patch diff --git a/0004-rar4-reader-protect-copy_from_lzss_window_to_unp-217.patch b/0004-rar4-reader-protect-copy_from_lzss_window_to_unp-217.patch new file mode 100644 index 0000000..e8330a2 --- /dev/null +++ b/0004-rar4-reader-protect-copy_from_lzss_window_to_unp-217.patch @@ -0,0 +1,119 @@ +From eac15e252010c1189a5c0f461364dbe2cd2a68b1 Mon Sep 17 00:00:00 2001 +From: "Dustin L. Howett" +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 +--- + 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 4fc6626c..5776df4b 100644 +--- a/libarchive/archive_read_support_format_rar.c ++++ b/libarchive/archive_read_support_format_rar.c +@@ -432,7 +432,7 @@ static int make_table_recurse(struct archive_read *, struct huffman_code *, int, + struct huffman_table_entry *, int, int); + static int expand(struct archive_read *, int64_t *); + static int copy_from_lzss_window_to_unp(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 *); + static int parse_filter(struct archive_read *, const uint8_t *, uint16_t, + uint8_t); +@@ -2060,7 +2060,7 @@ 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_to_unp(a, buff, rar->offset, (int)bs); ++ ret = copy_from_lzss_window_to_unp(a, buff, rar->offset, bs); + if (ret != ARCHIVE_OK) + return (ret); + rar->offset += bs; +@@ -2213,7 +2213,7 @@ 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_to_unp(a, buff, rar->offset, (int)bs); ++ ret = copy_from_lzss_window_to_unp(a, buff, rar->offset, bs); + if (ret != ARCHIVE_OK) + return (ret); + rar->offset += bs; +@@ -3094,11 +3094,16 @@ copy_from_lzss_window(struct archive_read *a, void *buffer, + + static int + copy_from_lzss_window_to_unp(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) +@@ -3110,17 +3115,17 @@ copy_from_lzss_window_to_unp(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], +@@ -3130,9 +3135,7 @@ copy_from_lzss_window_to_unp(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) +@@ -3140,6 +3143,11 @@ copy_from_lzss_window_to_unp(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 * +-- +2.45.1 + diff --git a/libarchive.spec b/libarchive.spec index fdc788d..d89ae19 100644 --- a/libarchive.spec +++ b/libarchive.spec @@ -2,7 +2,7 @@ Name: libarchive Version: 3.7.2 -Release: 5%{?dist} +Release: 6%{?dist} Summary: A library for handling streaming archive formats # Licenses: @@ -52,6 +52,10 @@ Patch0002: 0002-tests-fix-zstd-long-option-test-for-32-bit-architect.patch # Fixes Heap based buffer overflow in rar e8 filter (CVE-2024-26256) Patch0003: 0003-fix-OOB-in-rar-e8-filter.patch +# Upstream patch: https://github.com/libarchive/libarchive/commit/eac15e252010c1189a5c0f461364dbe2cd2a68b1 +# Fixes CVE-2024-20696 +Patch0004: 0004-rar4-reader-protect-copy_from_lzss_window_to_unp-217.patch + %description Libarchive is a programming library that can create and read several different streaming archive formats, including most popular tar variants, several cpio @@ -249,6 +253,10 @@ run_testsuite %changelog +* Thu Jun 06 2024 Lukas Javorsky - 3.7.2-6 +- Fix CVE-2024-20696 +- Resolves: RHEL-40042 + * Mon May 27 2024 Lukas Javorsky - 3.7.2-5 - Fix for CVE-2024-26256