mirror of
https://github.com/github/codeql.git
synced 2026-04-24 16:25:15 +02:00
47 lines
1.3 KiB
Plaintext
47 lines
1.3 KiB
Plaintext
/**
|
||
* @name Duplicate key in dict literal
|
||
* @description Duplicate key in dict literal. All but the last will be lost.
|
||
* @kind problem
|
||
* @tags quality
|
||
* maintainability
|
||
* useless-code
|
||
* external/cwe/cwe-561
|
||
* @problem.severity warning
|
||
* @sub-severity high
|
||
* @precision very-high
|
||
* @id py/duplicate-key-dict-literal
|
||
*/
|
||
|
||
import python
|
||
import semmle.python.strings
|
||
|
||
predicate dict_key(Dict d, Expr k, string s) {
|
||
k = d.getAKey() and
|
||
(
|
||
s = k.(Num).getN()
|
||
or
|
||
// We use <20> to mark unrepresentable characters
|
||
// so two instances of <20> may represent different strings in the source code
|
||
not "<22>" = s.charAt(_) and
|
||
exists(StringLiteral c | c = k |
|
||
s = "u\"" + c.getText() + "\"" and c.isUnicode()
|
||
or
|
||
s = "b\"" + c.getText() + "\"" and not c.isUnicode()
|
||
)
|
||
)
|
||
}
|
||
|
||
from Dict d, Expr k1, Expr k2
|
||
where
|
||
exists(string s | dict_key(d, k1, s) and dict_key(d, k2, s) and k1 != k2) and
|
||
(
|
||
exists(BasicBlock b, int i1, int i2 |
|
||
k1.getAFlowNode() = b.getNode(i1) and
|
||
k2.getAFlowNode() = b.getNode(i2) and
|
||
i1 < i2
|
||
)
|
||
or
|
||
k1.getAFlowNode().getBasicBlock().strictlyDominates(k2.getAFlowNode().getBasicBlock())
|
||
)
|
||
select k1, "Dictionary key " + repr(k1) + " is subsequently $@.", k2, "overwritten"
|