bugfix: off-by-one error (espressif#5648)

kokke · web-flow · commit 36ff4426985a · 2021-10-01T15:48:35.000+03:00
diff --git a/cores/esp32/libb64/cdecode.c b/cores/esp32/libb64/cdecode.c
@@ -12,7 +12,7 @@ static int base64_decode_value_signed(int8_t value_in){
   static const int8_t decoding[] = {62,-1,-1,-1,63,52,53,54,55,56,57,58,59,60,61,-1,-1,-1,-2,-1,-1,-1,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,-1,-1,-1,-1,-1,-1,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51};
   static const int8_t decoding_size = sizeof(decoding);
   value_in -= 43;
-  if (value_in < 0 || value_in > decoding_size) return -1;
+  if (value_in < 0 || value_in >= decoding_size) return -1;
   return decoding[(int)value_in];
 }
 

Original file line number	Diff line number	Diff line change
`@@ -12,7 +12,7 @@ static int base64_decode_value_signed(int8_t value_in){`
`12`	`12`	`static const int8_t decoding[] = {62,-1,-1,-1,63,52,53,54,55,56,57,58,59,60,61,-1,-1,-1,-2,-1,-1,-1,0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,-1,-1,-1,-1,-1,-1,26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,49,50,51};`
`13`	`13`	`static const int8_t decoding_size = sizeof(decoding);`
`14`	`14`	`value_in -= 43;`
`15`		`- if (value_in < 0 \|\| value_in > decoding_size) return -1;`
	`15`	`+ if (value_in < 0 \|\| value_in >= decoding_size) return -1;`
`16`	`16`	`return decoding[(int)value_in];`
`17`	`17`	`}`
`18`	`18`