diff options
Diffstat (limited to 'tools/net/bpf_jit_disasm.c')
-rw-r--r-- | tools/net/bpf_jit_disasm.c | 75 |
1 files changed, 61 insertions, 14 deletions
diff --git a/tools/net/bpf_jit_disasm.c b/tools/net/bpf_jit_disasm.c index 544b05a53b70..422d9abd666a 100644 --- a/tools/net/bpf_jit_disasm.c +++ b/tools/net/bpf_jit_disasm.c @@ -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(®ex, "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(®ex); - 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); } @@ -222,13 +236,15 @@ static unsigned int get_last_jit_image(char *haystack, size_t hlen, printf("%lx + <x>:\n", base); regfree(®ex); - return ulen; + *ilen = ulen; + return image; } static void usage(void) { printf("Usage: bpf_jit_disasm [...]\n"); printf(" -o Also display related opcodes (default: off).\n"); + printf(" -O <file> Write binary image of code to file, don't disassemble to stdout.\n"); printf(" -f <file> Read last image dump from file or stdin (default: klog).\n"); printf(" -h Display this help.\n"); } @@ -236,14 +252,21 @@ 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:")) != -1) { + while ((opt = getopt(argc, argv, "of:O:")) != -1) { switch (opt) { case 'o': opcodes = 1; break; + case 'O': + ofile = optarg; + break; case 'f': file = optarg; break; @@ -254,7 +277,6 @@ int main(int argc, char **argv) } bfd_init(); - memset(image, 0, sizeof(image)); kbuff = get_log_buff(file, &klen); if (!kbuff) { @@ -262,12 +284,37 @@ int main(int argc, char **argv) return -1; } - len = get_last_jit_image(kbuff, klen, image, sizeof(image)); - if (len > 0) - get_asm_insns(image, len, opcodes); - else + image = get_last_jit_image(kbuff, klen, &len); + if (!image) { fprintf(stderr, "No JIT image found!\n"); + goto done; + } + if (!ofile) { + get_asm_insns(image, len, opcodes); + goto done; + } + + ofd = open(ofile, O_WRONLY | O_CREAT | O_TRUNC, DEFFILEMODE); + if (ofd < 0) { + fprintf(stderr, "Could not open file %s for writing: ", ofile); + perror(NULL); + goto done; + } + pos = image; + do { + nr = write(ofd, pos, len); + if (nr < 0) { + fprintf(stderr, "Could not write data to %s: ", ofile); + perror(NULL); + goto done; + } + len -= nr; + pos += nr; + } while (len); + close(ofd); +done: put_log_buff(kbuff); + free(image); return 0; } |