Fix VTOY_LINUX_REMOUNT option does not work with latest linux kernel version. (#2661 #2674)

DMPATCH/dmpatch.c

@@ -53,6 +53,9 @@ typedef struct ko_param
     unsigned long sym_put_size;
     unsigned long kv_major;
     unsigned long ibt;
+    unsigned long kv_minor;
+    unsigned long blkdev_get_addr;
+    unsigned long blkdev_put_addr;
     unsigned long padding[1];
 }ko_param;
 
@@ -150,10 +153,11 @@ static volatile ko_param g_ko_param =
 
 #define vdebug(fmt, args...) if(kprintf) kprintf(KERN_ERR fmt, ##args)
 
+static unsigned int g_claim_ptr = 0;
 static unsigned char *g_get_patch[MAX_PATCH] = { NULL };
 static unsigned char *g_put_patch[MAX_PATCH] = { NULL };
 
-static void notrace dmpatch_restore_code(unsigned char *opCode)
+static void notrace dmpatch_restore_code(int bytes, unsigned char *opCode, unsigned int code)
 {
     unsigned long align;
 
@@ -161,7 +165,14 @@ static void notrace dmpatch_restore_code(unsigned char *opCode)
     {
         align = (unsigned long)opCode / g_ko_param.pgsize * g_ko_param.pgsize;
         set_mem_rw(align, 1);
-        *opCode = 0x80;
+        if (bytes == 1)
+        {
+            *opCode = (unsigned char)code;            
+        }
+        else
+        {
+            *(unsigned int *)opCode = code;
+        }
         set_mem_ro(align, 1);        
     }
 }
@@ -235,6 +246,121 @@ static int notrace dmpatch_replace_code
     return 0;
 }
 
+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;
+}
+
 #ifdef VTOY_IBT
 static __always_inline unsigned long long dmpatch_rdmsr(unsigned int msr)
 {
@@ -297,7 +423,8 @@ static int notrace dmpatch_init(void)
     
     kprintf = (printk_pf)(g_ko_param.printk_addr); 
 
-    vdebug("dmpatch_init start pagesize=%lu ...\n", g_ko_param.pgsize);
+    vdebug("dmpatch_init start pagesize=%lu kernel=%lu.%lu ...\n", 
+        g_ko_param.pgsize, g_ko_param.kv_major, g_ko_param.kv_minor);
     
     if (g_ko_param.struct_size != sizeof(ko_param))
     {
@@ -316,20 +443,27 @@ static int notrace dmpatch_init(void)
     reg_kprobe = (kprobe_reg_pf)g_ko_param.reg_kprobe_addr;
     unreg_kprobe = (kprobe_unreg_pf)g_ko_param.unreg_kprobe_addr;
 
-    r = dmpatch_replace_code(1, g_ko_param.sym_get_addr, g_ko_param.sym_get_size, 2, "dm_get_table_device", g_get_patch);
+    if (g_ko_param.kv_major > 6 || (g_ko_param.kv_major == 6 && g_ko_param.kv_minor >= 5))
-    if (r && g_ko_param.kv_major >= 5)
     {
-        vdebug("new2 patch dm_get_table_device...\n");
+        vdebug("new interface patch dm_get_table_device...\n");
-        r = dmpatch_replace_code(2, g_ko_param.sym_get_addr, g_ko_param.sym_get_size, 1, "dm_get_table_device", g_get_patch);
+        r = dmpatch_patch_claim_ptr();
+    }
+    else
+    {
+        r = dmpatch_replace_code(1, g_ko_param.sym_get_addr, g_ko_param.sym_get_size, 2, "dm_get_table_device", g_get_patch);
+        if (r && g_ko_param.kv_major >= 5)
+        {
+            vdebug("new2 patch dm_get_table_device...\n");
+            r = dmpatch_replace_code(2, g_ko_param.sym_get_addr, g_ko_param.sym_get_size, 1, "dm_get_table_device", g_get_patch);
+        }
+
+        if (r && g_ko_param.kv_major >= 5)
+        {
+            vdebug("new3 patch dm_get_table_device...\n");
+            r = dmpatch_replace_code(3, g_ko_param.sym_get_addr, g_ko_param.sym_get_size, 1, "dm_get_table_device", g_get_patch);
+        }
     }
 
-    if (r && g_ko_param.kv_major >= 5)
-    {
-        vdebug("new3 patch dm_get_table_device...\n");
-        r = dmpatch_replace_code(3, g_ko_param.sym_get_addr, g_ko_param.sym_get_size, 1, "dm_get_table_device", g_get_patch);
-    }
-    
-    
     if (r)
     {
         rc = -EINVAL;
@@ -337,7 +471,14 @@ static int notrace dmpatch_init(void)
     }
     vdebug("patch dm_get_table_device success\n");
 
-    r = dmpatch_replace_code(1, g_ko_param.sym_put_addr, g_ko_param.sym_put_size, 1, "dm_put_table_device", g_put_patch);
+    if (g_ko_param.kv_major >= 6 && g_ko_param.kv_minor >= 5)
+    {
+        r = 0;
+    }
+    else
+    {
+        r = dmpatch_replace_code(1, g_ko_param.sym_put_addr, g_ko_param.sym_put_size, 1, "dm_put_table_device", g_put_patch);        
+    }
     if (r)
     {
         rc = -EINVAL;
@@ -369,10 +510,18 @@ static void notrace dmpatch_exit(void)
         msr = dmpatch_ibt_save();
     }
 
-    for (i = 0; i < MAX_PATCH; i++)
+    if (g_claim_ptr)
     {
-        dmpatch_restore_code(g_get_patch[i]);
+        dmpatch_restore_code(4, g_get_patch[0], g_claim_ptr);
-        dmpatch_restore_code(g_put_patch[i]);
+        dmpatch_restore_code(4, g_put_patch[0], g_claim_ptr);
+    }
+    else
+    {        
+        for (i = 0; i < MAX_PATCH; i++)
+        {
+            dmpatch_restore_code(1, g_get_patch[i], 0x80);
+            dmpatch_restore_code(1, g_put_patch[i], 0x80);
+        }
     }
 
     vdebug("dmpatch_exit success\n");

IMG/cpio/ventoy/hook/ventoy-hook-lib.sh

@@ -344,6 +344,15 @@ ventoy_dm_patch() {
     get_addr=$(echo $vtLine | $AWK '{print $1}')
     get_size=$(echo $vtLine | $AWK '{print $2}')
 
+    vtLine=$($VTOY_PATH/tool/vtoyksym blkdev_get_by_dev $VTOY_PATH/kallsyms) 
+    vtlog "get blkdev_get_by_dev address $vtLine"        
+    blkdev_get_addr=$(echo $vtLine | $AWK '{print $1}')
+    
+    vtLine=$($VTOY_PATH/tool/vtoyksym blkdev_put $VTOY_PATH/kallsyms) 
+    vtlog "get blkdev_put address $vtLine"        
+    blkdev_put_addr=$(echo $vtLine | $AWK '{print $1}')
+    
+
     if $GREP -m1 -q 'close_table_device.isra' $VTOY_PATH/kallsyms; then
         vtLine=$($VTOY_PATH/tool/vtoyksym close_table_device.isra $VTOY_PATH/kallsyms)
         vtlog "get close_table_device.isra address $vtLine"
@@ -383,6 +392,7 @@ ventoy_dm_patch() {
     
     vtlog get_addr=$get_addr  get_size=$get_size
     vtlog put_addr=$put_addr  put_size=$put_size
+    vtlog blkdev_get_addr=$blkdev_get_addr blkdev_put_addr=$blkdev_put_addr
     vtlog kprobe_reg_addr=$kprobe_reg_addr  kprobe_unreg_addr=$kprobe_unreg_addr
     vtlog ro_addr=$ro_addr  rw_addr=$rw_addr  printk_addr=$printk_addr
 
@@ -397,6 +407,8 @@ ventoy_dm_patch() {
 
 
     vtKv=$($BUSYBOX_PATH/uname -r)
+    vtKVMajor=$(echo $vtKv | $AWK -F. '{print $1}')
+    vtKVMinor=$(echo $vtKv | $AWK -F. '{print $2}')
     
     if [ ! -d /lib/modules/$vtKv ]; then
         vtlog "No modules directory found"
@@ -437,13 +449,18 @@ ventoy_dm_patch() {
        
     
     #step1: modify vermagic/mod crc/relocation
-    vtlog "$VTOY_PATH/tool/vtoykmod -u $VTOY_PATH/tool/$vtKoName $VTOY_PATH/$vtModName $vtDebug"
+    vtlog "$VTOY_PATH/tool/vtoykmod -u $vtKVMajor $vtKVMinor $VTOY_PATH/tool/$vtKoName $VTOY_PATH/$vtModName $vtDebug"
-    $VTOY_PATH/tool/vtoykmod -u $VTOY_PATH/tool/$vtKoName $VTOY_PATH/$vtModName $vtDebug >>$VTLOG 2>&1
+    $VTOY_PATH/tool/vtoykmod -u $vtKVMajor $vtKVMinor $VTOY_PATH/tool/$vtKoName $VTOY_PATH/$vtModName $vtDebug >>$VTLOG 2>&1
     
     #step2: fill parameters
     vtPgsize=$($VTOY_PATH/tool/vtoyksym -p)
-    vtlog "$VTOY_PATH/tool/vtoykmod -f $VTOY_PATH/tool/$vtKoName $vtPgsize 0x$printk_addr 0x$ro_addr 0x$rw_addr $get_addr $get_size $put_addr $put_size 0x$kprobe_reg_addr 0x$kprobe_unreg_addr $vtKv $vtIBT $vtDebug"
+    
-    $VTOY_PATH/tool/vtoykmod -f $VTOY_PATH/tool/$vtKoName $vtPgsize 0x$printk_addr 0x$ro_addr 0x$rw_addr $get_addr $get_size $put_addr $put_size 0x$kprobe_reg_addr 0x$kprobe_unreg_addr $vtKv $vtIBT $vtDebug >>$VTLOG 2>&1
+    vtPrams="$VTOY_PATH/tool/$vtKoName $vtPgsize 0x$printk_addr 0x$ro_addr 0x$rw_addr $get_addr $get_size $put_addr $put_size 0x$kprobe_reg_addr 0x$kprobe_unreg_addr $vtKVMajor $vtIBT $vtKVMinor $blkdev_get_addr $blkdev_put_addr $vtDebug"
+    
+    
+    vtlog "$VTOY_PATH/tool/vtoykmod -f $vtPrams"
+    $VTOY_PATH/tool/vtoykmod -f $vtPrams >>$VTLOG 2>&1
+
 
     vtlog "insmod $VTOY_PATH/tool/$vtKoName"
     $BUSYBOX_PATH/insmod $VTOY_PATH/tool/$vtKoName  >>$VTLOG 2>&1

VtoyTool/vtoykmod.c

@@ -188,6 +188,9 @@ typedef struct ko_param
     unsigned long sym_put_size;
     unsigned long kv_major;
     unsigned long ibt;
+    unsigned long kv_minor;
+    unsigned long blkdev_get_addr;
+    unsigned long blkdev_put_addr;
     unsigned long padding[1];
 }ko_param;
 
@@ -243,7 +246,7 @@ static int vtoykmod_read_file(char *name, char **buf)
     return size;
 }
 
-static int vtoykmod_find_section64(char *buf, char *section, int *offset, int *len)
+static int vtoykmod_find_section64(char *buf, char *section, int *offset, int *len, Elf64_Shdr **shdr)
 {
     uint16_t i;
     int cmplen;
@@ -265,6 +268,10 @@ static int vtoykmod_find_section64(char *buf, char *section, int *offset, int *l
         {
             *offset = (int)(sec[i].sh_offset);
             *len = (int)(sec[i].sh_size);
+            if (shdr)
+            {
+                *shdr = sec + i;
+            }
             return 0;
         }
     }
@@ -272,7 +279,7 @@ static int vtoykmod_find_section64(char *buf, char *section, int *offset, int *l
     return 1;
 }
 
-static int vtoykmod_find_section32(char *buf, char *section, int *offset, int *len)
+static int vtoykmod_find_section32(char *buf, char *section, int *offset, int *len, Elf32_Shdr **shdr)
 {
     uint16_t i;
     int cmplen;
@@ -294,6 +301,10 @@ static int vtoykmod_find_section32(char *buf, char *section, int *offset, int *l
         {
             *offset = (int)(sec[i].sh_offset);
             *len = (int)(sec[i].sh_size);
+            if (shdr)
+            {
+                *shdr = sec + i;
+            }
             return 0;
         }
     }
@@ -411,7 +422,7 @@ static int vtoykmod_update_vermagic(char *oldbuf, int oldsize, char *newbuf, int
     return 0;
 }
 
-int vtoykmod_update(char *oldko, char *newko)
+int vtoykmod_update(int kvMajor, int kvMinor, char *oldko, char *newko)
 {
     int rc = 0;
     int modver = 0;
@@ -419,6 +430,7 @@ int vtoykmod_update(char *oldko, char *newko)
     int newoff, newlen;
     int oldsize, newsize;
     char *newbuf, *oldbuf;
+    Elf64_Shdr *sec = NULL;
 
     oldsize = vtoykmod_read_file(oldko, &oldbuf);
     newsize = vtoykmod_read_file(newko, &newbuf);
@@ -435,13 +447,13 @@ int vtoykmod_update(char *oldko, char *newko)
     {
         if (oldbuf[EI_CLASS] == ELFCLASS64)
         {
-            rc  = vtoykmod_find_section64(oldbuf, "__versions", &oldoff, &oldlen);
+            rc  = vtoykmod_find_section64(oldbuf, "__versions", &oldoff, &oldlen, NULL);
-            rc += vtoykmod_find_section64(newbuf, "__versions", &newoff, &newlen);            
+            rc += vtoykmod_find_section64(newbuf, "__versions", &newoff, &newlen, NULL);            
         }
         else
         {
-            rc  = vtoykmod_find_section32(oldbuf, "__versions", &oldoff, &oldlen);
+            rc  = vtoykmod_find_section32(oldbuf, "__versions", &oldoff, &oldlen, NULL);
-            rc += vtoykmod_find_section32(newbuf, "__versions", &newoff, &newlen);
+            rc += vtoykmod_find_section32(newbuf, "__versions", &newoff, &newlen, NULL);
         }
 
         if (rc == 0)
@@ -459,8 +471,8 @@ int vtoykmod_update(char *oldko, char *newko)
     {
         Elf64_Rela *oldRela, *newRela;
         
-        rc  = vtoykmod_find_section64(oldbuf, ".rela.gnu.linkonce.this_module", &oldoff, &oldlen);
+        rc  = vtoykmod_find_section64(oldbuf, ".rela.gnu.linkonce.this_module", &oldoff, &oldlen, NULL);
-        rc += vtoykmod_find_section64(newbuf, ".rela.gnu.linkonce.this_module", &newoff, &newlen);
+        rc += vtoykmod_find_section64(newbuf, ".rela.gnu.linkonce.this_module", &newoff, &newlen, NULL);
         if (rc == 0)
         {
             oldRela = (Elf64_Rela *)(oldbuf + oldoff);
@@ -478,13 +490,31 @@ int vtoykmod_update(char *oldko, char *newko)
         {
             debug("section .rela.gnu.linkonce.this_module not found\n");
         }
+
+        if (kvMajor > 6 || (kvMajor == 6 && kvMinor >= 3))
+        {
+            rc  = vtoykmod_find_section64(oldbuf, ".gnu.linkonce.this_module", &oldoff, &oldlen, &sec);
+            rc += vtoykmod_find_section64(newbuf, ".gnu.linkonce.this_module", &newoff, &newlen, NULL);
+            if (rc == 0)
+            {
+                debug("section .gnu.linkonce.this_module change oldlen:0x%x to newlen:0x%x\n", oldlen, newlen);
+                if (sec)
+                {
+                    sec->sh_size = newlen;                
+                }
+            }
+            else
+            {
+                debug("section .gnu.linkonce.this_module not found\n");
+            }
+        }
     }
     else
     {
         Elf32_Rel *oldRel, *newRel;
         
-        rc  = vtoykmod_find_section32(oldbuf, ".rel.gnu.linkonce.this_module", &oldoff, &oldlen);
+        rc  = vtoykmod_find_section32(oldbuf, ".rel.gnu.linkonce.this_module", &oldoff, &oldlen, NULL);
-        rc += vtoykmod_find_section32(newbuf, ".rel.gnu.linkonce.this_module", &newoff, &newlen);
+        rc += vtoykmod_find_section32(newbuf, ".rel.gnu.linkonce.this_module", &newoff, &newlen, NULL);
         if (rc == 0)
         {
             oldRel = (Elf32_Rel *)(oldbuf + oldoff);
@@ -542,8 +572,11 @@ int vtoykmod_fill_param(char **argv)
             param->sym_put_size = strtoul(argv[8], NULL, 10);
             param->reg_kprobe_addr = strtoul(argv[9], NULL, 16);
             param->unreg_kprobe_addr = strtoul(argv[10], NULL, 16);
-            param->kv_major = (unsigned long)(argv[11][0] - '0');
+            param->kv_major = strtoul(argv[11], NULL, 10);
             param->ibt = strtoul(argv[12], NULL, 16);;
+            param->kv_minor = strtoul(argv[13], NULL, 10);
+            param->blkdev_get_addr = strtoul(argv[14], NULL, 16);
+            param->blkdev_put_addr = strtoul(argv[15], NULL, 16);
 
             debug("pgsize=%lu (%s)\n", param->pgsize, argv[1]);
             debug("printk_addr=0x%lx (%s)\n", param->printk_addr, argv[2]);
@@ -557,6 +590,9 @@ int vtoykmod_fill_param(char **argv)
             debug("unreg_kprobe_addr=0x%lx (%s)\n", param->unreg_kprobe_addr, argv[10]);
             debug("kv_major=%lu (%s)\n", param->kv_major, argv[11]);
             debug("ibt=0x%lx (%s)\n", param->ibt, argv[12]);
+            debug("kv_minor=%lu (%s)\n", param->kv_minor, argv[13]);
+            debug("blkdev_get_addr=0x%lx (%s)\n", param->blkdev_get_addr, argv[14]);
+            debug("blkdev_put_addr=0x%lx (%s)\n", param->blkdev_put_addr, argv[15]);
             
             break;
         }
@@ -596,6 +632,8 @@ static int vtoykmod_check_ibt(void)
 int vtoykmod_main(int argc, char **argv)
 {
     int i;
+    int kvMajor = 0;
+    int kvMinor = 0;
 
     for (i = 0; i < argc; i++)
     {
@@ -612,7 +650,9 @@ int vtoykmod_main(int argc, char **argv)
     }
     else if (argv[1][0] == '-' && argv[1][1] == 'u')
     {
-        return vtoykmod_update(argv[2], argv[3]);
+        kvMajor = (int)strtol(argv[2], NULL, 10);
+        kvMinor = (int)strtol(argv[3], NULL, 10);
+        return vtoykmod_update(kvMajor, kvMinor, argv[4], argv[5]);
     }
     else if (argv[1][0] == '-' && argv[1][1] == 'I')
     {

VtoyTool/vtoyksym.c

@@ -21,6 +21,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <ctype.h>
 #include <errno.h>
 #include <unistd.h>
 
@@ -30,10 +31,12 @@ static int verbose = 0;
 int vtoyksym_main(int argc, char **argv)
 {
     int i;
+    int len = 0;
     unsigned long long addr1 = 0;
     unsigned long long addr2 = 0;
     char sym[256];
     char line[1024];
+    char *start = NULL;
     const char *name = NULL;
     FILE *fp;
 
@@ -68,9 +71,11 @@ int vtoyksym_main(int argc, char **argv)
     snprintf(sym, sizeof(sym), " %s", argv[1]);
     debug("lookup for <%s>\n", sym);
 
+    len = (int)strlen(sym);
     while (fgets(line, sizeof(line), fp))
     {
-        if (strstr(line, sym))
+        start = strstr(line, sym);
+        if (start && (start > line) && isspace(*(start + len)))
         {
             addr1 = strtoull(line, NULL, 16);
             if (!fgets(line, sizeof(line), fp))