Re: [PATCH] Revert "Input: bcm5974 - check endpoint type before starting traffic"

On 05.03.24 06:52, Javier Carrasco wrote:

This patch intended to fix an well-knonw issue in old drivers where the
endpoint type is taken for granted, which is often triggered by fuzzers.

That was the case for this driver [1], and although the fix seems to be
correct, it uncovered another issue that leads to a regression [2] if
the endpoints of the current interface are checked. The driver makes use
of endpoints that belong to a different interface rather than the one it
binds (it binds to the third interface, but also accesses an endpoint
from a different one). The driver should claim the interfaces it
requires, but that is still not the case.

Given that the regression is more severe than the issue found by
syzkaller, the best approach is reverting the patch that causes the
regression, and trying to fix the underlying problem before checking
the endpoint types again.

Note that reverting this patch will probably trigger the syzkaller bug
at some point.

quoted

[1] https://syzkaller.appspot.com/bug?extid=348331f63b034f89b622

[2] https://lore.kernel.org/linux-input/ab9d758c-3ce9-42f6-99af-877055a589e6@leemhuis.info/T/#t (local)

FWIW, these should be Link: or Closes tags, as explained in the docs.
And there is a better lore link. And there is the bugzilla entry as well.
Hence...
 

This reverts commit 2b9c3eb32a699acdd4784d6b93743271b4970899.

Fixes: b516b1b0dfcc ("Revert "Input: bcm5974 - check endpoint type before starting traffic"")

you might want to add them here like this:

 Link: https://syzkaller.appspot.com/bug?extid=348331f63b034f89b622 [1]
 Link: https://lore.kernel.org/linux-input/87sf161jjc.wl-tiwai@suse.de/ (local) [2]
 Link: https://bugzilla.suse.com/show_bug.cgi?id=1220030

In an ideal world we also would add a "Reported-by: Jacopo Radice" before
the bugzilla line, as the details in the suse bugtracker apparently is
public, but it's likely better to not go down that path.

Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>

Ciao, Thorsten