tools: bpf_jit_disasm: Handle large images.

Dynamically allocate memory so that JIT images larger than the size of
the statically allocated array can be handled.

Signed-off-by: David Daney <david.daney@cavium.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
David Daney 2017-06-13 16:49:35 -07:00 committed by David S. Miller
parent 2fae5d0e64
commit e274da1a50
1 changed files with 26 additions and 11 deletions

View File

@ -159,8 +159,8 @@ static void put_log_buff(char *buff)
free(buff);
}
static unsigned int get_last_jit_image(char *haystack, size_t hlen,
uint8_t *image, size_t ilen)
static uint8_t *get_last_jit_image(char *haystack, size_t hlen,
unsigned int *ilen)
{
char *ptr, *pptr, *tmp;
off_t off = 0;
@ -168,9 +168,10 @@ static unsigned int get_last_jit_image(char *haystack, size_t hlen,
regmatch_t pmatch[1];
unsigned long base;
regex_t regex;
uint8_t *image;
if (hlen == 0)
return 0;
return NULL;
ret = regcomp(&regex, "flen=[[:alnum:]]+ proglen=[[:digit:]]+ "
"pass=[[:digit:]]+ image=[[:xdigit:]]+", REG_EXTENDED);
@ -194,11 +195,22 @@ static unsigned int get_last_jit_image(char *haystack, size_t hlen,
&flen, &proglen, &pass, &base);
if (ret != 4) {
regfree(&regex);
return 0;
return NULL;
}
if (proglen > 1000000) {
printf("proglen of %d too big, stopping\n", proglen);
return NULL;
}
image = malloc(proglen);
if (!image) {
printf("Out of memory\n");
return NULL;
}
memset(image, 0, proglen);
tmp = ptr = haystack + off;
while ((ptr = strtok(tmp, "\n")) != NULL && ulen < ilen) {
while ((ptr = strtok(tmp, "\n")) != NULL && ulen < proglen) {
tmp = NULL;
if (!strstr(ptr, "JIT code"))
continue;
@ -208,10 +220,12 @@ static unsigned int get_last_jit_image(char *haystack, size_t hlen,
ptr = pptr;
do {
image[ulen++] = (uint8_t) strtoul(pptr, &pptr, 16);
if (ptr == pptr || ulen >= ilen) {
if (ptr == pptr) {
ulen--;
break;
}
if (ulen >= proglen)
break;
ptr = pptr;
} while (1);
}
@ -222,7 +236,8 @@ static unsigned int get_last_jit_image(char *haystack, size_t hlen,
printf("%lx + <x>:\n", base);
regfree(&regex);
return ulen;
*ilen = ulen;
return image;
}
static void usage(void)
@ -237,12 +252,12 @@ static void usage(void)
int main(int argc, char **argv)
{
unsigned int len, klen, opt, opcodes = 0;
static uint8_t image[32768];
char *kbuff, *file = NULL;
char *ofile = NULL;
int ofd;
ssize_t nr;
uint8_t *pos;
uint8_t *image = NULL;
while ((opt = getopt(argc, argv, "of:O:")) != -1) {
switch (opt) {
@ -262,7 +277,6 @@ int main(int argc, char **argv)
}
bfd_init();
memset(image, 0, sizeof(image));
kbuff = get_log_buff(file, &klen);
if (!kbuff) {
@ -270,8 +284,8 @@ int main(int argc, char **argv)
return -1;
}
len = get_last_jit_image(kbuff, klen, image, sizeof(image));
if (len <= 0) {
image = get_last_jit_image(kbuff, klen, &len);
if (!image) {
fprintf(stderr, "No JIT image found!\n");
goto done;
}
@ -301,5 +315,6 @@ int main(int argc, char **argv)
done:
put_log_buff(kbuff);
free(image);
return 0;
}