You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.

134 lines
3.7 KiB

diff --git a/src/softmagic.c b/src/softmagic.c
index 56f09ee..8d08cad 100644
--- a/src/softmagic.c
+++ b/src/softmagic.c
@@ -61,6 +61,7 @@ private void cvt_16(union VALUETYPE *, const struct magic *);
private void cvt_32(union VALUETYPE *, const struct magic *);
private void cvt_64(union VALUETYPE *, const struct magic *);
+#define OFFSET_OOB(n, o, i) ((n) < (o) || (i) > ((n) - (o)))
/*
* softmagic - lookup one file in parsed, in-memory copy of database
* Passed the name and FILE * of one file to be typed.
@@ -1081,7 +1082,7 @@ mget(struct magic_set *ms, const unsigned char *s,
}
switch (m->in_type) {
case FILE_BYTE:
- if (nbytes < (offset + 1))
+ if (OFFSET_OOB(nbytes, offset, 1))
return 0;
if (off) {
switch (m->in_op & FILE_OPS_MASK) {
@@ -1116,7 +1117,8 @@ mget(struct magic_set *ms, const unsigned char *s,
offset = ~offset;
break;
case FILE_BESHORT:
- if (nbytes < (offset + 2))
+
+ if (OFFSET_OOB(nbytes, offset, 2))
return 0;
if (off) {
switch (m->in_op & FILE_OPS_MASK) {
@@ -1168,7 +1170,7 @@ mget(struct magic_set *ms, const unsigned char *s,
offset = ~offset;
break;
case FILE_LESHORT:
- if (nbytes < (offset + 2))
+ if (OFFSET_OOB(nbytes, offset, 2))
return 0;
if (off) {
switch (m->in_op & FILE_OPS_MASK) {
@@ -1220,7 +1222,7 @@ mget(struct magic_set *ms, const unsigned char *s,
offset = ~offset;
break;
case FILE_SHORT:
- if (nbytes < (offset + 2))
+ if (OFFSET_OOB(nbytes, offset, 2))
return 0;
if (off) {
switch (m->in_op & FILE_OPS_MASK) {
@@ -1257,7 +1259,7 @@ mget(struct magic_set *ms, const unsigned char *s,
break;
case FILE_BELONG:
case FILE_BEID3:
- if (nbytes < (offset + 4))
+ if (OFFSET_OOB(nbytes, offset, 4))
return 0;
if (off) {
switch (m->in_op & FILE_OPS_MASK) {
@@ -1328,7 +1330,7 @@ mget(struct magic_set *ms, const unsigned char *s,
break;
case FILE_LELONG:
case FILE_LEID3:
- if (nbytes < (offset + 4))
+ if (OFFSET_OOB(nbytes, offset, 4))
return 0;
if (off) {
switch (m->in_op & FILE_OPS_MASK) {
@@ -1398,7 +1400,7 @@ mget(struct magic_set *ms, const unsigned char *s,
offset = ~offset;
break;
case FILE_MELONG:
- if (nbytes < (offset + 4))
+ if (OFFSET_OOB(nbytes, offset, 4))
return 0;
if (off) {
switch (m->in_op & FILE_OPS_MASK) {
@@ -1468,7 +1470,7 @@ mget(struct magic_set *ms, const unsigned char *s,
offset = ~offset;
break;
case FILE_LONG:
- if (nbytes < (offset + 4))
+ if (OFFSET_OOB(nbytes, offset, 4))
return 0;
if (off) {
switch (m->in_op & FILE_OPS_MASK) {
@@ -1535,14 +1537,14 @@ mget(struct magic_set *ms, const unsigned char *s,
/* Verify we have enough data to match magic type */
switch (m->type) {
case FILE_BYTE:
- if (nbytes < (offset + 1)) /* should alway be true */
+ if (OFFSET_OOB(nbytes, offset, 1))
return 0;
break;
case FILE_SHORT:
case FILE_BESHORT:
case FILE_LESHORT:
- if (nbytes < (offset + 2))
+ if (OFFSET_OOB(nbytes, offset, 2))
return 0;
break;
@@ -1561,26 +1563,26 @@ mget(struct magic_set *ms, const unsigned char *s,
case FILE_FLOAT:
case FILE_BEFLOAT:
case FILE_LEFLOAT:
- if (nbytes < (offset + 4))
+ if (OFFSET_OOB(nbytes, offset, 4))
return 0;
break;
case FILE_DOUBLE:
case FILE_BEDOUBLE:
case FILE_LEDOUBLE:
- if (nbytes < (offset + 8))
+ if (OFFSET_OOB(nbytes, offset, 8))
return 0;
break;
case FILE_STRING:
case FILE_PSTRING:
case FILE_SEARCH:
- if (nbytes < (offset + m->vallen))
+ if (OFFSET_OOB(nbytes, offset, m->vallen))
return 0;
break;
case FILE_REGEX:
- if (nbytes < offset)
+ if (OFFSET_OOB(nbytes, offset, 0))
return 0;
break;