diff options
Diffstat (limited to 'meta-networking/recipes-support/dovecot/dovecot/0010-lib-mail-message-parser-Support-limiting-max-number-.patch')
| -rw-r--r-- | meta-networking/recipes-support/dovecot/dovecot/0010-lib-mail-message-parser-Support-limiting-max-number-.patch | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/meta-networking/recipes-support/dovecot/dovecot/0010-lib-mail-message-parser-Support-limiting-max-number-.patch b/meta-networking/recipes-support/dovecot/dovecot/0010-lib-mail-message-parser-Support-limiting-max-number-.patch new file mode 100644 index 00000000000..ae525446658 --- /dev/null +++ b/meta-networking/recipes-support/dovecot/dovecot/0010-lib-mail-message-parser-Support-limiting-max-number-.patch @@ -0,0 +1,188 @@ +From df9e0d358ef86e3342525dcdefcf79dc2d749a30 Mon Sep 17 00:00:00 2001 +From: Timo Sirainen <timo.sirainen@open-xchange.com> +Date: Thu, 23 Apr 2020 16:59:40 +0300 +Subject: [PATCH 10/13] lib-mail: message-parser - Support limiting max number + of nested MIME parts + +The default is to allow 100 nested MIME parts. When the limit is reached, +the innermost MIME part's body contains all the rest of the inner bodies +until a parent MIME part is reached. +--- + src/lib-mail/message-parser.c | 43 +++++++++++++++++++++++++++++++------- + src/lib-mail/test-message-parser.c | 31 +++++++++++++++++++++++++++ + 2 files changed, 67 insertions(+), 7 deletions(-) + +Signed-off-by: Sana Kazi <Sana.Kazi@kpit.com> + +CVE: CVE-2020-12100 +Upstream-Status: Backport [http://archive.ubuntu.com/ubuntu/pool/main/d/dovecot/dovecot_2.2.33.2-1ubuntu4.7.debian.tar.xz] +Comment: No change in any hunk + +diff --git a/src/lib-mail/message-parser.c b/src/lib-mail/message-parser.c +index 8970d8e0e..721615f76 100644 +--- a/src/lib-mail/message-parser.c ++++ b/src/lib-mail/message-parser.c +@@ -13,6 +13,8 @@ + #define BOUNDARY_STRING_MAX_LEN (70 + 10) + #define BOUNDARY_END_MAX_LEN (BOUNDARY_STRING_MAX_LEN + 2 + 2) + ++#define MESSAGE_PARSER_DEFAULT_MAX_NESTED_MIME_PARTS 100 ++ + struct message_boundary { + struct message_boundary *next; + +@@ -28,9 +30,11 @@ struct message_parser_ctx { + struct istream *input; + struct message_part *parts, *part; + const char *broken_reason; ++ unsigned int nested_parts_count; + + enum message_header_parser_flags hdr_flags; + enum message_parser_flags flags; ++ unsigned int max_nested_mime_parts; + + char *last_boundary; + struct message_boundary *boundaries; +@@ -206,6 +210,8 @@ message_part_append(struct message_parser_ctx *ctx) + ctx->next_part = &part->children; + + ctx->part = part; ++ ctx->nested_parts_count++; ++ i_assert(ctx->nested_parts_count < ctx->max_nested_mime_parts); + } + + static void message_part_finish(struct message_parser_ctx *ctx) +@@ -213,8 +219,12 @@ static void message_part_finish(struct message_parser_ctx *ctx) + struct message_part **const *parent_next_partp; + unsigned int count = array_count(&ctx->next_part_stack); + ++ i_assert(ctx->nested_parts_count > 0); ++ ctx->nested_parts_count--; ++ + parent_next_partp = array_idx(&ctx->next_part_stack, count-1); + array_delete(&ctx->next_part_stack, count-1, 1); ++ + ctx->next_part = *parent_next_partp; + + message_size_add(&ctx->part->parent->body_size, &ctx->part->body_size); +@@ -592,6 +602,11 @@ static bool block_is_at_eoh(const struct message_block *block) + return FALSE; + } + ++static bool parse_too_many_nested_mime_parts(struct message_parser_ctx *ctx) ++{ ++ return ctx->nested_parts_count > ctx->max_nested_mime_parts; ++} ++ + #define MUTEX_FLAGS \ + (MESSAGE_PART_FLAG_MESSAGE_RFC822 | MESSAGE_PART_FLAG_MULTIPART) + +@@ -616,8 +631,12 @@ static int parse_next_header(struct message_parser_ctx *ctx, + "\n--boundary" belongs to us or to a previous boundary. + this is a problem if the boundary prefixes are identical, + because MIME requires only the prefix to match. */ +- parse_next_body_multipart_init(ctx); +- ctx->multipart = TRUE; ++ if (!parse_too_many_nested_mime_parts(ctx)) { ++ parse_next_body_multipart_init(ctx); ++ ctx->multipart = TRUE; ++ } else { ++ part->flags &= ~MESSAGE_PART_FLAG_MULTIPART; ++ } + } + + /* before parsing the header see if we can find a --boundary from here. +@@ -721,12 +740,16 @@ static int parse_next_header(struct message_parser_ctx *ctx, + i_assert(ctx->last_boundary == NULL); + ctx->multipart = FALSE; + ctx->parse_next_block = parse_next_body_to_boundary; +- } else if (part->flags & MESSAGE_PART_FLAG_MESSAGE_RFC822) ++ } else if ((part->flags & MESSAGE_PART_FLAG_MESSAGE_RFC822) != 0 && ++ !parse_too_many_nested_mime_parts(ctx)) { + ctx->parse_next_block = parse_next_body_message_rfc822_init; +- else if (ctx->boundaries != NULL) +- ctx->parse_next_block = parse_next_body_to_boundary; +- else +- ctx->parse_next_block = parse_next_body_to_eof; ++ } else { ++ part->flags &= ~MESSAGE_PART_FLAG_MESSAGE_RFC822; ++ if (ctx->boundaries != NULL) ++ ctx->parse_next_block = parse_next_body_to_boundary; ++ else ++ ctx->parse_next_block = parse_next_body_to_eof; ++ } + + ctx->want_count = 1; + +@@ -1100,6 +1123,8 @@ message_parser_init_int(struct istream *input, + ctx = i_new(struct message_parser_ctx, 1); + ctx->hdr_flags = hdr_flags; + ctx->flags = flags; ++ ctx->max_nested_mime_parts = ++ MESSAGE_PARSER_DEFAULT_MAX_NESTED_MIME_PARTS; + ctx->input = input; + i_stream_ref(input); + return ctx; +@@ -1159,6 +1184,10 @@ int message_parser_deinit_from_parts(struct message_parser_ctx **_ctx, + if (ctx->hdr_parser_ctx != NULL) + message_parse_header_deinit(&ctx->hdr_parser_ctx); + boundary_remove_until(ctx, NULL); ++ /* caller might have stopped the parsing early */ ++ i_assert(ctx->nested_parts_count == 0 || ++ i_stream_have_bytes_left(ctx->input)); ++ + i_stream_unref(&ctx->input); + if (array_is_created(&ctx->next_part_stack)) + array_free(&ctx->next_part_stack); +diff --git a/src/lib-mail/test-message-parser.c b/src/lib-mail/test-message-parser.c +index 94aa3eb7c..481d05942 100644 +--- a/src/lib-mail/test-message-parser.c ++++ b/src/lib-mail/test-message-parser.c +@@ -166,6 +166,36 @@ static void test_message_parser_small_blocks(void) + test_end(); + } + ++static void test_message_parser_stop_early(void) ++{ ++ struct message_parser_ctx *parser; ++ struct istream *input; ++ struct message_part *parts; ++ struct message_block block; ++ unsigned int i; ++ pool_t pool; ++ int ret; ++ ++ test_begin("message parser stop early"); ++ pool = pool_alloconly_create("message parser", 10240); ++ input = test_istream_create(test_msg); ++ ++ test_istream_set_allow_eof(input, FALSE); ++ for (i = 1; i <= TEST_MSG_LEN+1; i++) { ++ i_stream_seek(input, 0); ++ test_istream_set_size(input, i); ++ parser = message_parser_init(pool, input, 0, 0); ++ while ((ret = message_parser_parse_next_block(parser, ++ &block)) > 0) ; ++ test_assert(ret == 0); ++ message_parser_deinit(&parser, &parts); ++ } ++ ++ i_stream_unref(&input); ++ pool_unref(&pool); ++ test_end(); ++} ++ + static void test_message_parser_truncated_mime_headers(void) + { + static const char input_msg[] = +@@ -740,6 +770,7 @@ int main(void) + { + static void (*test_functions[])(void) = { + test_message_parser_small_blocks, ++ test_message_parser_stop_early, + test_message_parser_truncated_mime_headers, + test_message_parser_truncated_mime_headers2, + test_message_parser_truncated_mime_headers3, +-- +2.11.0 + |