Menu
I have this line of code:
this.Path = pathLookUpLocation.GetValue(RegLookupKey, null).ToString();
When I run static analysis tool (Coverity) on my code I get a FORWARD_NULL here, saying that I am dereferencing null here. I am having trouble understanding what that means and how I would go about fixing it?
this.Path is a string, pathLookUpLocation is a RegistryKey, RegLookupKey is a string.
501
A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. NULL pointer dereference issues can occur through a number of flaws, including race conditions, and simple programming omissions.
Dereferencing a null pointer always results in undefined behavior and can cause crashes. If the compiler finds a pointer dereference, it treats that pointer as nonnull. As a result, the optimizer may remove null equality checks for dereferenced pointers.
ABSTRACT Null pointer dereference (NPD) is a widespread vulnerability that occurs whenever an executing program attempts to dereference a null pointer. NPD vulnerability can be exploited by hackers to maliciously crash a process to cause a denial of service or execute an arbitrary code under specific conditions.
when a pointer is initialized to NULL, getting "FORWARD_NULL" coverity errors and when the NULL initialization is removed, it throws UNINIT coverity errors.
You can over come "testing for null after dereference" by not doing that. In other words, by testing for null before the indirection. Simply swap those two lines. is dereferencing dtcStatus (via the * operator).
The compiler warns that you may be dereferencing null when you write the property message.Length because its static analysis determines that message may be null. You may know that IsNotNull provides a null check, and when it returns true, the null-state of message should be not-null.
Without the null-forgiving operator, the compiler generates the following warning for the p.Name code: Warning CS8602: Dereference of a possibly null reference. If you can modify the IsValid method, you can use the NotNullWhen attribute to inform the compiler that an argument of the IsValid method cannot be null when the method returns true:
Thank you. Available in C# 8.0 and later, the unary postfix ! operator is the null-forgiving, or null-suppression, operator. In an enabled nullable annotation context, you use the null-forgiving operator to declare that expression x of a reference type isn't null: x!. The unary prefix ! operator is the logical negation operator.
I suppose pathLookUpLocation is of type RegistryKey.
The reason for this message is that your code will throw a NullReferenceException if the value with the key specified by RegLookupKey is not found. This happens, because you pass null as the second parameter to GetValue. The second parameter is the default value that is returned if the key can't be found.
Fix it by changing it to string.Empty:
this.Path = pathLookUpLocation.GetValue(RegLookupKey, string.Empty).ToString();
If you love us? You can donate to us via Paypal or buy me a coffee so we can maintain and grow! Thank you!
Donate Us With
