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charset="UTF-8" Content-Transfer-Encoding: quoted-printable On Mon, 2024-09-23 at 23:33 +0100, David Howells wrote: > Eduard Zingerman wrote: >=20 > > - null-ptr-deref is triggered by access to page->pcp_list.next > > when list_del() is called from page_alloc.c:__rmqueue_pcplist(), >=20 > Can you tell me what the upstream commit ID of your kernel is? (before a= ny > patches are stacked on it) I used bpf-next tree, but could be reproduced with [1] as well, commit ID [2]. Decoded dmesg for this commit ID in [3]. [1] git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git [2] abf2050f51fd ("Merge tag 'media/v6.12-1' of git://git.kernel.org/pub/sc= m/linux/kernel/git/mchehab/linux-media") [3] https://gist.github.com/eddyz87/af39e04069c6ca30e66c3032c0384b8e > If you can modify your kernel, can you find the following in fs/netfs/: >=20 > buffered_read.c:127: new =3D kmalloc(sizeof(*new), GFP_NOFS); > buffered_read.c:353: folioq =3D kmalloc(sizeof(*folioq), GFP_KERNEL); > buffered_read.c:458: folioq =3D kmalloc(sizeof(*folioq), GFP_KERNEL); > misc.c:25: tail =3D kmalloc(sizeof(*tail), GFP_NOFS); >=20 > and change the kmalloc to kzalloc? No changes in behaviour. --=-Q91RsiEvrT2A6vPIbGYO Content-Type: text/html; charset="utf-8" Content-Transfer-Encoding: quoted-printable 
On Mon, 2024-09-23 at 23:33 +0=
100, David Howells wrote:
> Eduard Zingerman <eddyz87@gmail=
.com> wrote:
> 
> > - null-ptr-deref is tri=
ggered by access to page->pcp_list.next
> >   when list_=
del() is called from page_alloc.c:__rmqueue_pcplist(),
> 
> Can you tell me what the upstream commit ID of your kernel is?  =
(before any
> patches are stacked on it)

<=
pre>I used bpf-next tree, but could be reproduced with [1] as well,
commit ID [2]. Decoded dmesg for this commit ID in [3].

[1] git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.g=
it
[2] abf2050f51fd ("Merge tag 'media/v6.12-1' of git://git.kern=
el.org/pub/scm/linux/kernel/git/mchehab/linux-media")
[3] https:/=
/gist.github.com/eddyz87/af39e04069c6ca30e66c3032c0384b8e

> If you can modify your kernel, can you find the following in f=
s/netfs/:
> 
> buffered_read.c:127:			new =3D kma=
lloc(sizeof(*new), GFP_NOFS);
> buffered_read.c:353:	folioq =
=3D kmalloc(sizeof(*folioq), GFP_KERNEL);
> buffered_read.c:45=
8:	folioq =3D kmalloc(sizeof(*folioq), GFP_KERNEL);
> misc.c:2=
5:		tail =3D kmalloc(sizeof(*tail), GFP_NOFS);
> 
&g=
t; and change the kmalloc to kzalloc?

No changes i=
n behaviour.



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