From ed4afd451f12ea57f9aaaf6f8442eee7e415fa1a Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 15 May 2014 15:56:38 -0700 Subject: [PATCH] tools: bpf_jit_disasm: ignore image address for disasm seccomp filters use kernel JIT image addresses, so bpf_jit_enable=2 prints [ 20.146438] flen=3 proglen=82 pass=0 image=0000000000000000 [ 20.146442] JIT code: 00000000: 55 48 89 e5 48 81 ec 28 02 00 00 ... ignore image address, so that seccomp filters can be disassembled Signed-off-by: Alexei Starovoitov Acked-by: Daniel Borkmann Signed-off-by: David S. Miller --- tools/net/bpf_jit_disasm.c | 18 ++++++++---------- 1 file changed, 8 insertions(+), 10 deletions(-) diff --git a/tools/net/bpf_jit_disasm.c b/tools/net/bpf_jit_disasm.c index cfe0cdcda3de..d9730c3319b9 100644 --- a/tools/net/bpf_jit_disasm.c +++ b/tools/net/bpf_jit_disasm.c @@ -43,8 +43,7 @@ static void get_exec_path(char *tpath, size_t size) free(path); } -static void get_asm_insns(uint8_t *image, size_t len, unsigned long base, - int opcodes) +static void get_asm_insns(uint8_t *image, size_t len, int opcodes) { int count, i, pc = 0; char tpath[256]; @@ -107,13 +106,13 @@ static void put_klog_buff(char *buff) } static int get_last_jit_image(char *haystack, size_t hlen, - uint8_t *image, size_t ilen, - unsigned long *base) + uint8_t *image, size_t ilen) { char *ptr, *pptr, *tmp; off_t off = 0; int ret, flen, proglen, pass, ulen = 0; regmatch_t pmatch[1]; + unsigned long base; regex_t regex; if (hlen == 0) @@ -136,7 +135,7 @@ static int get_last_jit_image(char *haystack, size_t hlen, ptr = haystack + off - (pmatch[0].rm_eo - pmatch[0].rm_so); ret = sscanf(ptr, "flen=%d proglen=%d pass=%d image=%lx", - &flen, &proglen, &pass, base); + &flen, &proglen, &pass, &base); if (ret != 4) return 0; @@ -162,7 +161,7 @@ static int get_last_jit_image(char *haystack, size_t hlen, assert(ulen == proglen); printf("%d bytes emitted from JIT compiler (pass:%d, flen:%d)\n", proglen, pass, flen); - printf("%lx + :\n", *base); + printf("%lx + :\n", base); regfree(®ex); return ulen; @@ -172,7 +171,6 @@ int main(int argc, char **argv) { int len, klen, opcodes = 0; char *kbuff; - unsigned long base; uint8_t image[4096]; if (argc > 1) { @@ -189,9 +187,9 @@ int main(int argc, char **argv) kbuff = get_klog_buff(&klen); - len = get_last_jit_image(kbuff, klen, image, sizeof(image), &base); - if (len > 0 && base > 0) - get_asm_insns(image, len, base, opcodes); + len = get_last_jit_image(kbuff, klen, image, sizeof(image)); + if (len > 0) + get_asm_insns(image, len, opcodes); put_klog_buff(kbuff); -- 2.20.1