Re: ASan reports use-after-free when running munmap-pthread

[Richard Henderson]

On 2/2/23 09:06, Anton Johansson wrote:
> Hi,
>
> I was running check-tcg with ASan enabled on master, and ran into
> the following use-after-free. There appears to be a race between
> jump cache invalidation and thread destruction (?)
>
> I thought I'd post here since I noticed some previous discussion on the
> topic, and I'm not sure myself what a proper fix would look like.
>
> Tested on arm/aarch64/x86_64-linux-user.
>
> Here's a snippet of the ASan output:
> =================================================================
> ==187529==ERROR: AddressSanitizer: heap-use-after-free on address 0x62d000f433b0 at pc 
> 0x55cfefe00246 bp 0x7f4725f400b0 sp 0x7f4725f400a0

The fix for this was merged today:

4731f89b3b cpu: free cpu->tb_jmp_cache with RCU

I'd forgotten about this, since the pull request was pending for some time, while we 
waited for CI minutes to refresh.


r~