76 lines
2.7 KiB
Diff
76 lines
2.7 KiB
Diff
From fb3fba9eac65291b20f22eb956f02490d62de3ec Mon Sep 17 00:00:00 2001
|
|
From: Lars Kanis <kanis@comcard.de>
|
|
Date: Thu, 19 Oct 2023 18:32:31 +0200
|
|
Subject: [PATCH] Fix possible buffer overflows on 32 bit systems
|
|
|
|
Comparing pointers after adding lengths is dangerous, since the length can overflow the pointer, so that the comparison leads to wrong results.
|
|
Comparing lengths only fixes this issue.
|
|
|
|
This lead to segfault in the following spec on x86:
|
|
|
|
it "should raise an error at grabage COPY format" do
|
|
expect{ decoder.decode("123\t \0\\\t\\") }
|
|
.to raise_error(ArgumentError, /premature.*at position: 7$/)
|
|
end
|
|
---
|
|
ext/pg_copy_coder.c | 14 +++++++-------
|
|
1 file changed, 7 insertions(+), 7 deletions(-)
|
|
|
|
diff --git a/ext/pg_copy_coder.c b/ext/pg_copy_coder.c
|
|
index 16d5c15..f2fe029 100644
|
|
--- a/ext/pg_copy_coder.c
|
|
+++ b/ext/pg_copy_coder.c
|
|
@@ -795,26 +795,26 @@ pg_bin_dec_copy_row(t_pg_coder *conv, const char *input_line, int len, int _tupl
|
|
cur_ptr = input_line;
|
|
line_end_ptr = input_line + len;
|
|
|
|
- if (cur_ptr + 11 <= line_end_ptr && memcmp(cur_ptr, BinarySignature, 11) == 0){
|
|
+ if (line_end_ptr - cur_ptr >= 11 && memcmp(cur_ptr, BinarySignature, 11) == 0){
|
|
/* binary COPY header signature detected -> just drop it */
|
|
int ext_bytes;
|
|
cur_ptr += 11;
|
|
|
|
/* read flags */
|
|
- if (cur_ptr + 4 > line_end_ptr) goto length_error;
|
|
+ if (line_end_ptr - cur_ptr < 4 ) goto length_error;
|
|
cur_ptr += 4;
|
|
|
|
/* read header extensions */
|
|
- if (cur_ptr + 4 > line_end_ptr) goto length_error;
|
|
+ if (line_end_ptr - cur_ptr < 4 ) goto length_error;
|
|
ext_bytes = read_nbo32(cur_ptr);
|
|
if (ext_bytes < 0) goto length_error;
|
|
cur_ptr += 4;
|
|
- if (cur_ptr + ext_bytes > line_end_ptr) goto length_error;
|
|
+ if (line_end_ptr - cur_ptr < ext_bytes ) goto length_error;
|
|
cur_ptr += ext_bytes;
|
|
}
|
|
|
|
/* read row header */
|
|
- if (cur_ptr + 2 > line_end_ptr) goto length_error;
|
|
+ if (line_end_ptr - cur_ptr < 2 ) goto length_error;
|
|
nfields = read_nbo16(cur_ptr);
|
|
cur_ptr += 2;
|
|
|
|
@@ -830,7 +830,7 @@ pg_bin_dec_copy_row(t_pg_coder *conv, const char *input_line, int len, int _tupl
|
|
VALUE field_value;
|
|
|
|
/* read field size */
|
|
- if (cur_ptr + 4 > line_end_ptr) goto length_error;
|
|
+ if (line_end_ptr - cur_ptr < 4 ) goto length_error;
|
|
input_len = read_nbo32(cur_ptr);
|
|
cur_ptr += 4;
|
|
|
|
@@ -839,7 +839,7 @@ pg_bin_dec_copy_row(t_pg_coder *conv, const char *input_line, int len, int _tupl
|
|
/* NULL indicator */
|
|
rb_ary_push(array, Qnil);
|
|
} else {
|
|
- if (cur_ptr + input_len > line_end_ptr) goto length_error;
|
|
+ if (line_end_ptr - cur_ptr < input_len ) goto length_error;
|
|
|
|
/* copy input data to field_str */
|
|
PG_RB_STR_ENSURE_CAPA( field_str, input_len, output_ptr, end_capa_ptr );
|
|
--
|
|
2.42.0
|
|
|