On Wed, Mar 12, 2025 at 06:04:02PM +0400, Edgar Khachatryan wrote: > My name is Edgar Khachatryan, and I am a student currently working on a > project that involves static analysis using Sparse. I have encountered an > issue where running Sparse with the command "sparse file.c" does not detect > simple memory issues such as memory leaks, double frees, or use-after-free > errors in a single file. Sparse doesn't look for those kinds of bugs. You're better off using Smatch for that. With Smatch, I've never really looked for memory leaks. It's quite a hard problem and I've never been able to do it in a useful way without introducing a lot of false positives. $ ./smatch test.c test.c:4:18: warning: non-ANSI function declaration of function 'memory_leak' test.c:13:18: warning: non-ANSI function declaration of function 'double_free' test.c:23:21: warning: non-ANSI function declaration of function 'use_after_free' test.c:33:10: warning: non-ANSI function declaration of function 'main' test.c:20 double_free() error: double free of 'ptr' test.c:30 use_after_free() error: dereferencing freed memory 'ptr' $ But the other problem with Smatch is that it's only ever really used on the kernel so user space support is proof of concept quality. I had to push a quick patch it to make it find the use after free bug. I use a different check for check_free_strict.c module for kernel code. https://github.com/error27/smatch/commit/993d157ab147720b558f0f6293dd4acfeb0d2a18 regards, dan carpenter
