Re: [syzbot ci] Re: Compiler-Based Capability- and Locking-Analysis

Marco Elver
2025-09-19T07:06:05Z

On Thu, Sep 18, 2025 at 12:41PM -0700, syzbot ci wrote:
> syzbot ci has tested the following series
>
> [v3] Compiler-Based Capability- and Locking-Analysis
[...]
> and found the following issue:
> general protection fault in validate_page_before_insert
>
> Full report is available here:
> https://ci.syzbot.org/series/81182522-74c0-4494-bcf8-976133df7dc7
>
> ***
>
> general protection fault in validate_page_before_insert

Thanks, syzbot ci!

I messed up the type when moving kcov->area access inside the critical
section. This is the fix:

fixup! kcov: Enable capability analysis

diff --git a/kernel/kcov.c b/kernel/kcov.c
index 1897c8ca6209..e81e3c0d01c6 100644
--- a/kernel/kcov.c
+++ b/kernel/kcov.c
@@ -497,7 +497,7 @@ static int kcov_mmap(struct file *filep, struct vm_area_struct *vma)
unsigned long size, off;
struct page *page;
unsigned long flags;
- unsigned long *area;
+ void *area;

spin_lock_irqsave(&kcov->lock, flags);
size = kcov->size * sizeof(unsigned long);