From 03b10383c9c0e48922fa8d8e419c9c75881dbecd Mon Sep 17 00:00:00 2001
From: Linus Torvalds <torvalds@linux-foundation.org>
Date: Sat, 7 Oct 2017 13:25:24 -0700
Subject: [PATCH] Fix divinglog import limit checking

The divinglog import did horrible things with the strings returned from
the sqlite queries, and ended up using uninitialized values at the end
of the secondary profile data strings.

This rewrites the import logic to track the length of the strings
properly when importing the divinglog data.

We should run 'valgrind' a whole lot more than we do, I suspect.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Dirk Hohndel <dirk@hohndel.org>
---
 core/parse-xml.c | 189 ++++++++++++++++++++++++++---------------------
 1 file changed, 103 insertions(+), 86 deletions(-)

diff --git a/core/parse-xml.c b/core/parse-xml.c
index ece85022b..303f974ed 100644
--- a/core/parse-xml.c
+++ b/core/parse-xml.c
@@ -43,9 +43,13 @@ struct dive_table *target_table = NULL;
  * Return value: length of the trimmed string, excluding the terminal 0x0 byte
  * The original pointer (buffer) remains valid after this function has been called
  * and points to the trimmed string */
-int trimspace(char *buffer) {
+int trimspace(char *buffer)
+{
 	int i, size, start, end;
 	size = strlen(buffer);
+
+	if (!size)
+		return 0;
 	for(start = 0; isspace(buffer[start]); start++)
 		if (start >= size) return 0;	// Find 1st character following leading whitespace
 	for(end = size - 1; isspace(buffer[end]); end--) // Find last character before trailing whitespace
@@ -3204,6 +3208,18 @@ extern int divinglog_cylinder(void *handle, int columns, char **data, char **col
 	return 0;
 }
 
+static int atoi_n(char *ptr, unsigned int len)
+{
+	if (len < 10) {
+		char buf[10];
+
+		memcpy(buf, ptr, len);
+		buf[len] = 0;
+		return atoi(buf);
+	}
+	return 0;
+}
+
 extern int divinglog_profile(void *handle, int columns, char **data, char **column)
 {
 	(void) handle;
@@ -3211,8 +3227,9 @@ extern int divinglog_profile(void *handle, int columns, char **data, char **colu
 	(void) column;
 
 	int sinterval = 0;
-	unsigned long i, len, lenprofile2 = 0;
-	char *ptr, temp[4], pres[5], hbeat[4], stop[4], stime[4], ndl[4], ppo2_1[4], ppo2_2[4], ppo2_3[4], cns[5], setpoint[3];
+	unsigned long time;
+	int len1, len2, len3, len4, len5;
+	char *ptr1, *ptr2, *ptr3, *ptr4, *ptr5;
 	short oldcyl = -1;
 
 	/* We do not have samples */
@@ -3252,54 +3269,74 @@ extern int divinglog_profile(void *handle, int columns, char **data, char **colu
 	 *
 	 */
 
-	len = strlen(data[1]);
+	ptr1 = data[1];
+	ptr2 = data[2];
+	ptr3 = data[3];
+	ptr4 = data[4];
+	ptr5 = data[5];
+	len1 = strlen(ptr1);
+	len2 = ptr2 ? strlen(ptr2) : 0;
+	len3 = ptr3 ? strlen(ptr3) : 0;
+	len4 = ptr4 ? strlen(ptr4) : 0;
+	len5 = ptr5 ? strlen(ptr5) : 0;
 
-	if (data[2])
-		lenprofile2 = strlen(data[2]);
-
-	for (i = 0, ptr = data[1]; i * 12 < len; ++i) {
+	time = 0;
+	while (len1 >= 12) {
 		sample_start();
 
-		cur_sample->time.seconds = sinterval * i;
-		cur_sample->in_deco = ptr[5] - '0' ? true : false;
-		ptr[5] = 0;
-		cur_sample->depth.mm = atoi(ptr) * 10;
+		cur_sample->time.seconds = time;
+		cur_sample->in_deco = ptr1[5] - '0' ? true : false;
+		cur_sample->depth.mm = atoi_n(ptr1, 5) * 10;
 
-		if (i * 11 < lenprofile2) {
-			memcpy(temp, &data[2][i * 11], 3);
-			cur_sample->temperature.mkelvin = C_to_mkelvin(atoi(temp) / 10);
+		if (len2 >= 11) {
+			int temp = atoi_n(ptr2, 3);
+			int pressure = atoi_n(ptr2+3, 4);
+			int tank = atoi_n(ptr2+7, 1);
+			int rbt = atoi_n(ptr2+8, 3) * 60;
+
+			cur_sample->temperature.mkelvin = C_to_mkelvin(temp / 10);
+			cur_sample->pressure[0].mbar = pressure * 100;
+			if (oldcyl != tank) {
+				struct gasmix *mix = &cur_dive->cylinder[tank].gasmix;
+				int o2 = get_o2(mix);
+				int he = get_he(mix);
+
+				event_start();
+				cur_event.time.seconds = time;
+				strcpy(cur_event.name, "gaschange");
+
+				o2 = (o2 + 5) / 10;
+				he = (he + 5) / 10;
+				cur_event.value = o2 + (he << 16);
+
+				event_end();
+				oldcyl = tank;
+			}
+
+			ptr2 += 11; len2 -= 11;
 		}
 
-		if (data[2]) {
-			memcpy(pres, &data[2][i * 11 + 3], 4);
-			cur_sample->pressure[0].mbar = atoi(pres) * 100;
+		if (len3 >= 14) {
+			cur_sample->heartbeat = atoi_n(ptr3+8, 3);
+			ptr3 += 14; len3 -= 14;
 		}
 
-		if (data[3] && strlen(data[3])) {
-			memcpy(hbeat, &data[3][i * 14 + 8], 3);
-			cur_sample->heartbeat = atoi(hbeat);
-		}
-
-		if (data[4] && strlen(data[4])) {
-			memcpy(stop, &data[4][i * 9 + 6], 3);
-			cur_sample->stopdepth.mm = atoi(stop) * 1000;
-
-			memcpy(stime, &data[4][i * 9 + 3], 3);
-			cur_sample->stoptime.seconds = atoi(stime) * 60;
-
+		if (len4 >= 9) {
 			/*
 			 * Following value is NDL when not in deco, and
 			 * either 0 or TTS when in deco.
 			 */
-
-			memcpy(ndl, &data[4][i * 9 + 0], 3);
-			if (cur_sample->in_deco == false)
-				cur_sample->ndl.seconds = atoi(ndl) * 60;
-			else if (atoi(ndl))
-				cur_sample->tts.seconds = atoi(ndl) * 60;
-
-			if (cur_sample->in_deco == true)
+			int val = atoi_n(ptr4, 3);
+			if (cur_sample->in_deco) {
 				cur_sample->ndl.seconds = 0;
+				if (val)
+					cur_sample->tts.seconds = val * 60;
+			} else {
+				cur_sample->ndl.seconds = val * 60;
+			}
+			cur_sample->stoptime.seconds = atoi_n(ptr4+3, 3) * 60;
+			cur_sample->stopdepth.mm = atoi_n(ptr4+6, 3) * 1000;
+			ptr4 += 9; len4 -= 9;
 		}
 
 		/*
@@ -3316,24 +3353,25 @@ extern int divinglog_profile(void *handle, int columns, char **data, char **colu
 		 * 1.12 bar, 1.13 bar, 1.14 bar, OTU = 154.8, CNS = 26.4, Setpoint = 1.1
 		 */
 
-		if (data[5] && strlen(data[5])) {
-			memcpy(ppo2_1, &data[5][i * 19 + 0], 3);
-			memcpy(ppo2_2, &data[5][i * 19 + 3], 3);
-			memcpy(ppo2_3, &data[5][i * 19 + 6], 3);
-			memcpy(cns, &data[5][i * 19 + 13], 4);
-			memcpy(setpoint, &data[5][i * 19 + 17], 2);
-
-			if (atoi(ppo2_1) > 0)
-				cur_sample->o2sensor[0].mbar = atoi(ppo2_1) * 100;
-			if (atoi(ppo2_2) > 0)
-				cur_sample->o2sensor[1].mbar = atoi(ppo2_2) * 100;
-			if (atoi(ppo2_3) > 0)
-				cur_sample->o2sensor[2].mbar = atoi(ppo2_3) * 100;
-			if (atoi(cns) > 0)
-				cur_sample->cns = lrintf(atoi(cns) / 10.0f);
-			if (atoi(setpoint) > 0)
-				cur_sample->setpoint.mbar = atoi(setpoint) * 100;
+		if (len5 >= 19) {
+			int ppo2_1 = atoi_n(ptr5 + 0, 3);
+			int ppo2_2 = atoi_n(ptr5 + 3, 3);
+			int ppo2_3 = atoi_n(ptr5 + 6, 3);
+			int otu = atoi_n(ptr5 + 9, 4);
+			int cns = atoi_n(ptr5 + 13, 4);
+			int setpoint = atoi_n(ptr5 + 17, 2);
 
+			if (ppo2_1 > 0)
+				cur_sample->o2sensor[0].mbar = ppo2_1 * 100;
+			if (ppo2_2 > 0)
+				cur_sample->o2sensor[1].mbar = ppo2_2 * 100;
+			if (ppo2_3 > 0)
+				cur_sample->o2sensor[2].mbar = ppo2_3 * 100;
+			if (cns > 0)
+				cur_sample->cns = lrintf(cns / 10.0f);
+			if (setpoint > 0)
+				cur_sample->setpoint.mbar = setpoint * 100;
+			ptr5 += 19; len5 -= 19;
 		}
 
 		/*
@@ -3346,63 +3384,42 @@ extern int divinglog_profile(void *handle, int columns, char **data, char **colu
 				 cur_sample->o2sensor[2].mbar ? 1 : 0;
 		}
 
-		ptr += 12;
 		sample_end();
-	}
 
-	for (i = 0, ptr = data[1]; i * 12 < len; ++i) {
 		/* Remaining bottom time warning */
-		if (ptr[6] - '0') {
+		if (ptr1[6] - '0') {
 			event_start();
-			cur_event.time.seconds = sinterval * i;
+			cur_event.time.seconds = time;
 			strcpy(cur_event.name, "rbt");
 			event_end();
 		}
 
 		/* Ascent warning */
-		if (ptr[7] - '0') {
+		if (ptr1[7] - '0') {
 			event_start();
-			cur_event.time.seconds = sinterval * i;
+			cur_event.time.seconds = time;
 			strcpy(cur_event.name, "ascent");
 			event_end();
 		}
 
 		/* Deco stop ignored */
-		if (ptr[8] - '0') {
+		if (ptr1[8] - '0') {
 			event_start();
-			cur_event.time.seconds = sinterval * i;
+			cur_event.time.seconds = time;
 			strcpy(cur_event.name, "violation");
 			event_end();
 		}
 
 		/* Workload warning */
-		if (ptr[9] - '0') {
+		if (ptr1[9] - '0') {
 			event_start();
-			cur_event.time.seconds = sinterval * i;
+			cur_event.time.seconds = time;
 			strcpy(cur_event.name, "workload");
 			event_end();
 		}
-		ptr += 12;
-	}
 
-	for (i = 0; i * 11 < lenprofile2; ++i) {
-		short tank = data[2][i * 11 + 7] - '0';
-		if (oldcyl != tank) {
-			struct gasmix *mix = &cur_dive->cylinder[tank].gasmix;
-			int o2 = get_o2(mix);
-			int he = get_he(mix);
-
-			event_start();
-			cur_event.time.seconds = sinterval * i;
-			strcpy(cur_event.name, "gaschange");
-
-			o2 = (o2 + 5) / 10;
-			he = (he + 5) / 10;
-			cur_event.value = o2 + (he << 16);
-
-			event_end();
-			oldcyl = tank;
-		}
+		ptr1 += 12; len1 -= 12;
+		time += sinterval;
 	}
 
 	return 0;