From: Max Khon <fjoe@samodelkin.net>
Date: Wed, 22 Jun 2022 21:02:06 +0000 (+0300)
Subject: fr_sbuff_extend_file(): update "end" of parent sbuffs (#4576)
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=4ac945626a0b3dddd65b609c8b5049ffffe77e7c;p=thirdparty%2Ffreeradius-server.git

fr_sbuff_extend_file(): update "end" of parent sbuffs (#4576)

This fixes parsing when streaming from file and parsed object (string)
spans fhe I/O buffer boundary.
---

diff --git a/src/lib/util/sbuff.c b/src/lib/util/sbuff.c
index 419b5dd4726..5ca3a8bc936 100644
--- a/src/lib/util/sbuff.c
+++ b/src/lib/util/sbuff.c
@@ -256,6 +256,7 @@ size_t fr_sbuff_shift(fr_sbuff_t *sbuff, size_t shift)
  */
 size_t fr_sbuff_extend_file(fr_sbuff_t *sbuff, size_t extension)
 {
+	fr_sbuff_t		*sbuff_i;
 	size_t			read, available, total_read;
 	fr_sbuff_uctx_file_t	*fctx;
 
@@ -290,7 +291,9 @@ size_t fr_sbuff_extend_file(fr_sbuff_t *sbuff, size_t extension)
 	}
 
 	read = fread(sbuff->end, 1, available, fctx->file);
-	sbuff->end += read;	/* Advance end, which increases fr_sbuff_remaining() */
+	for (sbuff_i = sbuff; sbuff_i; sbuff_i = sbuff_i->parent) {
+		sbuff_i->end += read;	/* Advance end, which increases fr_sbuff_remaining() */
+	}
 
 	/** Check for errors
 	 */
diff --git a/src/lib/util/sbuff_tests.c b/src/lib/util/sbuff_tests.c
index 754bda62a1d..b188c3129b0 100644
--- a/src/lib/util/sbuff_tests.c
+++ b/src/lib/util/sbuff_tests.c
@@ -1007,23 +1007,40 @@ static void test_talloc_extend_with_marker(void)
 static void test_file_extend(void)
 {
 	fr_sbuff_t	sbuff;
+	fr_sbuff_t	our_sbuff;
 	fr_sbuff_uctx_file_t	fctx;
 	FILE		*fp;
 	char		buff[16];
+	char		out[16 + 1];
 	char		fbuff[] = "                        xyzzy";
 	char		*post_ws;
+	ssize_t		slen;
 
 	TEST_CASE("Initialization");
 	fp = fmemopen(fbuff, sizeof(fbuff) - 1, "r");
 	TEST_CHECK(fp != NULL);
 	TEST_CHECK(fr_sbuff_init_file(&sbuff, &fctx, buff, sizeof(buff), fp, 128) == &sbuff);
+	our_sbuff = FR_SBUFF_BIND_CURRENT(&sbuff);
 
 	TEST_CASE("Advance past whitespace, which will require shift/extend");
-	TEST_CHECK_LEN(sizeof(fbuff) - 6, fr_sbuff_adv_past_whitespace(&sbuff, SIZE_MAX, NULL));
+	TEST_CHECK_LEN(fr_sbuff_adv_past_whitespace(&our_sbuff, SIZE_MAX, NULL), sizeof(fbuff) - 6);
 	TEST_CASE("Verify that we passed all and only whitespace");
-	(void) fr_sbuff_out_abstrncpy(NULL, &post_ws, &sbuff, 24);
+	(void) fr_sbuff_out_abstrncpy(NULL, &post_ws, &our_sbuff, 24);
 	TEST_CHECK_STRCMP(post_ws, "xyzzy");
 	talloc_free(post_ws);
+	TEST_CASE("Verify parent buffer end");
+	TEST_CHECK(sbuff.end == our_sbuff.end);
+
+	TEST_CASE("Verify that we do not read shifted buffer past eof");
+	slen = fr_sbuff_out_bstrncpy(&FR_SBUFF_OUT(out, sizeof(out)), &our_sbuff, SIZE_MAX);
+	TEST_CHECK_SLEN(slen, 0);
+	slen = fr_sbuff_out_bstrncpy_exact(&FR_SBUFF_OUT(out, sizeof(out)), &our_sbuff, SIZE_MAX);
+	TEST_CHECK_SLEN(slen, 0);
+	slen = fr_sbuff_out_bstrncpy_until(&FR_SBUFF_OUT(out, sizeof(out)), &our_sbuff, SIZE_MAX, NULL, NULL);
+	TEST_CHECK_SLEN(slen, 0);
+	slen = fr_sbuff_out_bstrncpy_allowed(&FR_SBUFF_OUT(out, sizeof(out)), &our_sbuff, SIZE_MAX, allow_lowercase_and_space);
+	TEST_CHECK_SLEN(slen, 0);
+
 	fclose(fp);
 }