+static unsigned long dmpatch_find_call_offset(unsigned long addr, unsigned long size, unsigned long func)
+{
+ unsigned long i = 0;
+ unsigned long dest;
+ unsigned char *opCode = NULL;
+ unsigned char aucOffset[8] = { 0, 0, 0, 0, 0xFF, 0xFF, 0xFF, 0xFF };
+
+ opCode = (unsigned char *)addr;
+
+ for (i = 0; i + 4 < size; i++)
+ {
+ if (opCode[i] == 0xE8)
+ {
+ aucOffset[0] = opCode[i + 1];
+ aucOffset[1] = opCode[i + 2];
+ aucOffset[2] = opCode[i + 3];
+ aucOffset[3] = opCode[i + 4];
+
+ dest = addr + i + 5 + *(unsigned long *)aucOffset;
+ if (dest == func)
+ {
+ return i;
+ }
+ }
+ }
+
+ return 0;
+}
+
+static unsigned int dmpatch_patch_claim_ptr(void)
+{
+ unsigned long i = 0;
+ unsigned long t = 0;
+ unsigned long offset1;
+ unsigned long offset2;
+ unsigned long align;
+ unsigned char *opCode = NULL;
+
+ vdebug("Get addr: 0x%lx %lu 0x%lx\n", g_ko_param.sym_get_addr, g_ko_param.sym_get_size, g_ko_param.blkdev_get_addr);
+ vdebug("Put addr: 0x%lx %lu 0x%lx\n", g_ko_param.sym_put_addr, g_ko_param.sym_put_size, g_ko_param.blkdev_put_addr);
+
+ opCode = (unsigned char *)g_ko_param.sym_get_addr;
+ for (i = 0; i < 4; i++)
+ {
+ vdebug("%02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X %02X\n",
+ opCode[i + 0], opCode[i + 1], opCode[i + 2], opCode[i + 3],
+ opCode[i + 4], opCode[i + 5], opCode[i + 6], opCode[i + 7],
+ opCode[i + 8], opCode[i + 9], opCode[i + 10], opCode[i + 11],
+ opCode[i + 12], opCode[i + 13], opCode[i + 14], opCode[i + 15]);
+ }
+
+ offset1 = dmpatch_find_call_offset(g_ko_param.sym_get_addr, g_ko_param.sym_get_size, g_ko_param.blkdev_get_addr);
+ offset2 = dmpatch_find_call_offset(g_ko_param.sym_put_addr, g_ko_param.sym_put_size, g_ko_param.blkdev_put_addr);
+ if (offset1 == 0 || offset2 == 0)
+ {
+ vdebug("call blkdev_get or blkdev_put Not found, %lu %lu\n", offset1, offset2);
+ return 1;
+ }
+ vdebug("call addr1:0x%lx call addr2:0x%lx\n",
+ g_ko_param.sym_get_addr + offset1,
+ g_ko_param.sym_put_addr + offset2);
+
+ opCode = (unsigned char *)g_ko_param.sym_get_addr;
+ for (i = offset1 - 1, t = 0; (i > 0) && (t < 24); i--, t++)
+ {
+ /* rdx */
+ if (opCode[i] == 0x48 && opCode[i + 1] == 0xc7 && opCode[i + 2] == 0xc2)
+ {
+ g_claim_ptr = *(unsigned int *)(opCode + i + 3);
+ g_get_patch[0] = opCode + i + 3;
+ vdebug("claim_ptr(%08X) found at get addr 0x%lx\n", g_claim_ptr, g_ko_param.sym_get_addr + i + 3);
+ break;
+ }
+ }
+
+ if (g_claim_ptr == 0)
+ {
+ vdebug("Claim_ptr not found in get\n");
+ return 1;
+ }
+
+ opCode = (unsigned char *)g_ko_param.sym_put_addr;
+ for (i = offset2 - 1, t = 0; (i > 0) && (t < 24); i--, t++)
+ {
+ /* rsi */
+ if (opCode[i] == 0x48 && opCode[i + 1] == 0xc7 && opCode[i + 2] == 0xc6)
+ {
+ if (*(unsigned int *)(opCode + i + 3) == g_claim_ptr)
+ {
+ vdebug("claim_ptr found at put addr 0x%lx\n", g_ko_param.sym_put_addr + i + 3);
+ g_put_patch[0] = opCode + i + 3;
+ break;
+ }
+ }
+ }
+
+ if (g_put_patch[0] == 0)
+ {
+ vdebug("Claim_ptr not found in put\n");
+ return 1;
+ }
+
+ align = (unsigned long)g_get_patch[0] / g_ko_param.pgsize * g_ko_param.pgsize;
+ set_mem_rw(align, 1);
+ *(unsigned int *)(g_get_patch[0]) = 0;
+ set_mem_ro(align, 1);
+
+ align = (unsigned long)g_put_patch[0] / g_ko_param.pgsize * g_ko_param.pgsize;
+ set_mem_rw(align, 1);
+ *(unsigned int *)(g_put_patch[0]) = 0;
+ set_mem_ro(align, 1);
+
+ return 0;
+}
+