Skip to content

Allow void* pointer arithmetic with sizeof #225

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
geoffw0 merged 1 commit into from
Sep 25, 2018
Merged

Allow void* pointer arithmetic with sizeof #225

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
11 changes: 6 additions & 5 deletions cpp/ql/src/Security/CWE/CWE-468/SuspiciousAddWithSizeof.ql
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -13,18 +13,19 @@
import cpp
import IncorrectPointerScalingCommon

private predicate isCharPtrExpr(Expr e) {
private predicate isCharSzPtrExpr(Expr e) {
exists (PointerType pt
| pt = e.getFullyConverted().getUnderlyingType()
| pt.getBaseType().getUnspecifiedType() instanceof CharType)
| pt.getBaseType().getUnspecifiedType() instanceof CharType
or pt.getBaseType().getUnspecifiedType() instanceof VoidType)
}

from Expr sizeofExpr, Expr e
where
// If we see an addWithSizeof then we expect the type of
// the pointer expression to be char*. Otherwise it is probably
// a mistake.
addWithSizeof(e, sizeofExpr, _) and not isCharPtrExpr(e)
// the pointer expression to be char* or void*. Otherwise it
// is probably a mistake.
addWithSizeof(e, sizeofExpr, _) and not isCharSzPtrExpr(e)
select
sizeofExpr,
"Suspicious sizeof offset in a pointer arithmetic expression. " +
Expand Down