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> Some people will say, I just want to get stuff done and not worry about all this safety junk. As someone who works in security and have exploited bugs in C/C+

> Some people will say, I just want to get stuff done and not worry about all this safety junk. As someone who works in security and have exploited bugs in C/C++ programs, this is pretty much why we wound up with so many CVEs. Are constructions like these really the root cause of CVEs? As long as you do a correct check, then you're all good. If Rust can do the same thing in fewer lines, then that may or may not be a good thing because some people might want a lower degree of abstraction or a greater one.

nneonneo 4y ago
Oh absolutely! Here’s an example from 2019: https://www.cve.org/CVERecord?id=CVE-2019-15900 https://www.cve.org/CVERecord?id=CVE-2019-15900 “An issue was discovered in slicer69 doas before 6.2 on certain platforms other than OpenBSD. On platforms without strtonum(3), sscanf was used without checking for error cases. Instead, the uninitialized variable errstr was checked and in some cases returned success even if sscanf failed. The result was that, instead of reporting that the supplied username or group name did not exist, it would execute the command as root.” Fail to check that your input parsed correctly, wind up with privilege escalation to root.
- netr0ute 4y ago
  The problem here is that that implementation was written in plain old C and is super unsafe, and is NOT C++. I don't know why C keeps getting confused with C++ because the two are basically totally different now.
  - nneonneo 4y ago
    Oh my bad! That must be why C++, a definitely not super unsafe language that is basically totally different from C, lets you do this: char buf[10]; std::cin >> buf; std::cout << buf << std::endl; g++ -Wall -std=c++2a (sorry, I’ve only got GCC 9), no warnings or errors, happily overruns the stack when fed more than 10 characters. This code is essentially equivalent to the C gets(buf) (splitting on whitespace instead of newline), but gets is deprecated and generates big warnings on most modern C compilers. Yet, operator>>(char *) does not. Sure, you can write secure code in C++. You can write secure code in C too, even if that language is “super unsafe”. But neither language will stop you from writing insecure code either.

nneonneo 4y ago

Oh absolutely! Here’s an example from 2019: https://www.cve.org/CVERecord?id=CVE-2019-15900 https://www.cve.org/CVERecord?id=CVE-2019-15900 “An issue was discovered in slicer69 doas before 6.2 on certain platforms other than OpenBSD. On platforms without strtonum(3), sscanf was used without checking for error cases. Instead, the uninitialized variable errstr was checked and in some cases returned success even if sscanf failed. The result was that, instead of reporting that the supplied username or group name did not exist, it would execute the command as root.” Fail to check that your input parsed correctly, wind up with privilege escalation to root.

netr0ute 4y ago
The problem here is that that implementation was written in plain old C and is super unsafe, and is NOT C++. I don't know why C keeps getting confused with C++ because the two are basically totally different now.
- nneonneo 4y ago
  Oh my bad! That must be why C++, a definitely not super unsafe language that is basically totally different from C, lets you do this: char buf[10]; std::cin >> buf; std::cout << buf << std::endl; g++ -Wall -std=c++2a (sorry, I’ve only got GCC 9), no warnings or errors, happily overruns the stack when fed more than 10 characters. This code is essentially equivalent to the C gets(buf) (splitting on whitespace instead of newline), but gets is deprecated and generates big warnings on most modern C compilers. Yet, operator>>(char *) does not. Sure, you can write secure code in C++. You can write secure code in C too, even if that language is “super unsafe”. But neither language will stop you from writing insecure code either.