On Sun, 24 Sep 2023 09:58:53 +0200, Otto Moerbeek wrote:
> The wayland issue was found as well, using the same method.
> I'm working on programming the heuristic that is quite effective into
> malloc itself. It currently looks like this for the X case above:
>
> X(67417) in malloc(): write to free
On Wed, Sep 20, 2023 at 08:08:23AM +0200, Otto Moerbeek wrote:
> On Sun, Sep 03, 2023 at 09:21:18AM +0200, Otto Moerbeek wrote:
>
> > Hello,
> >
> > I'm seeing some reports of "write after free" reported by malloc by
> > peolpe running current. Malloc has become more strict since begining
> > o
On Wed, Sep 20, 2023 at 03:02:27PM +0200, Matthieu Herrb wrote:
> On Wed, Sep 20, 2023 at 08:08:23AM +0200, Otto Moerbeek wrote:
> >
> > The other, a write after free that crashed the X server when running
> > picard was diagnosed by me. This one was a bit nasty, as it required
> > instrumenting
On Wed, Sep 20, 2023 at 08:08:23AM +0200, Otto Moerbeek wrote:
>
> The other, a write after free that crashed the X server when running
> picard was diagnosed by me. This one was a bit nasty, as it required
> instrumenting malloc to print some extra info to find the root cause.
>
> The bug is t
On Sun, Sep 03, 2023 at 09:21:18AM +0200, Otto Moerbeek wrote:
> Hello,
>
> I'm seeing some reports of "write after free" reported by malloc by
> peolpe running current. Malloc has become more strict since begining
> of June. Let me explain:
>
> Small allocations share a page. e.g. a 4k page wi
On Sun, Sep 03, 2023 at 09:30:49AM +0200, Otto Moerbeek wrote:
> > You can also be set upon a wrong foot: if an out of bounds write on a
> > adjacent chunk happens and lands in (another) free chunk, upon
> > allocation of that free chunk it will be reported as a "write after
> > free" case. It mig
On Sun, Sep 03, 2023 at 09:21:18AM +0200, Otto Moerbeek wrote:
> Hello,
>
> I'm seeing some reports of "write after free" reported by malloc by
> peolpe running current. Malloc has become more strict since begining
> of June. Let me explain:
>
> Small allocations share a page. e.g. a 4k page wi
Hello,
I'm seeing some reports of "write after free" reported by malloc by
peolpe running current. Malloc has become more strict since begining
of June. Let me explain:
Small allocations share a page. e.g. a 4k page will hold 8 512 byte
allocations.
When one such allocation is freed, it will be
