From: David Daney Date: Tue, 13 Jun 2017 23:49:35 +0000 (-0700) Subject: tools: bpf_jit_disasm: Handle large images. X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=e274da1a50f6f3c8216e5bb22e1b0964ab993f13;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git 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 Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- diff --git a/tools/net/bpf_jit_disasm.c b/tools/net/bpf_jit_disasm.c index ad572e6cdbd0..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); } @@ -222,7 +236,8 @@ static unsigned int get_last_jit_image(char *haystack, size_t hlen, printf("%lx + :\n", base); regfree(®ex); - 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; }