Subject: Re: Test patch for KASAN: global-out-of-bounds Read in detach_capi_ctr

From: Greg KH <[email-masked]>
Date: Mon, 4 Jul 2022 13:54:17 +0200

On Mon, Jul 04, 2022 at 02:26:19PM +0300, Dan Carpenter wrote:
> 
> On Fri, Jul 01, 2022 at 06:08:29AM -0700, Soumya Negi wrote:
> > #syz test: git://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
> > 3f8a27f9e27bd78604c0709224cec0ec85a8b106
> > 
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> 
> > From 3aa5aaffef64a5574cbdb3f5c985bc25b612140c Mon Sep 17 00:00:00 2001
> > From: Soumya Negi <[email-masked]>
> > Date: Fri, 1 Jul 2022 04:52:17 -0700
> > Subject: [PATCH] isdn: capi: Add check for controller count in
> >  detach_capi_ctr()
> > 
> > Fixes Syzbot bug:
> > https://syzkaller.appspot.com/bug?id=14f4820fbd379105a71fdee357b0759b90587a4e
> > 
> > This patch checks whether any ISDN devices are registered before unregistering
> > a CAPI controller(device). Without the check, the controller struct capi_str
> > results in out-of-bounds access bugs to other CAPI data strucures in
> > detach_capri_ctr() as seen in the bug report.
> > 
> 
> This bug was already fixed by commit 1f3e2e97c003 ("isdn: cpai: check
> ctr->cnr to avoid array index out of bound").
> 
> It just needs to be backported.  Unfortunately there was no Fixes tag so
> it wasn't picked up.  Also I'm not sure how backports work in netdev.

That commit has already been backported quite a while ago and is in the
following releases:
	4.4.290 4.9.288 4.14.253 4.19.214 5.4.156 5.10.76 5.14.15 5.15

thanks,

greg k-h