libavutil/rc4.c:44: error: Buffer Overrun L2
  Offset: [0, 510] Size: 256.

libavutil/rc4.c:30:10: <Offset trace>
28.     uint8_t x, y;
29.     uint8_t state[256];
30.     for (i = 0; i < 256; i++)
             ^
31.         state[i] = i;
32.     y = 0;

libavutil/rc4.c:30:10: Assignment
28.     uint8_t x, y;
29.     uint8_t state[256];
30.     for (i = 0; i < 256; i++)
             ^
31.         state[i] = i;
32.     y = 0;

libavutil/rc4.c:31:9: Assignment
29.     uint8_t state[256];
30.     for (i = 0; i < 256; i++)
31.         state[i] = i;
            ^
32.     y = 0;
33.     // j is i % keylen

libavutil/rc4.c:42:9: Assignment
40.     x = 1; y = state[1];
41.     while (datalen-- > 0) {
42.         uint8_t sum = state[x] + state[y];
            ^
43.         FFSWAP(uint8_t, state[x], state[y]);
44.         *data++ ^= state[sum];

libavutil/rc4.c:26:1: <Length trace>
24. #include "rc4.h"
25. 
26. void ff_rc4_enc(const uint8_t *key, int keylen, uint8_t *data, int datalen) {
    ^
27.     int i, j;
28.     uint8_t x, y;

libavutil/rc4.c:26:1: Array declaration
24. #include "rc4.h"
25. 
26. void ff_rc4_enc(const uint8_t *key, int keylen, uint8_t *data, int datalen) {
    ^
27.     int i, j;
28.     uint8_t x, y;

libavutil/rc4.c:44:20: Array access: Offset: [0, 510] Size: 256
42.         uint8_t sum = state[x] + state[y];
43.         FFSWAP(uint8_t, state[x], state[y]);
44.         *data++ ^= state[sum];
                       ^
45.         x++;
46.         y += state[x];
