ALSA: hdspm: Hardening for potential Spectre v1
commit7625e9fd5fa9862bce433a36a42d7364e4a6ba3f
authorTakashi Iwai <tiwai@suse.de>
Tue, 24 Apr 2018 06:03:14 +0000 (24 08:03 +0200)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 2 May 2018 14:53:41 +0000 (2 07:53 -0700)
tree09c14a8a53e051b873029eb0dd1bca78ed699eaf
parent257e7b73ffb602eebc940f6bd5415355d32d293c
ALSA: hdspm: Hardening for potential Spectre v1

commit 10513142a7114d251670361ad40cba2c61403406 upstream.

As recently Smatch suggested, a couple of places in HDSP MADI driver
may expand the array directly from the user-space value with
speculation:
  sound/pci/rme9652/hdspm.c:5717 snd_hdspm_channel_info() warn: potential spectre issue 'hdspm->channel_map_out' (local cap)
  sound/pci/rme9652/hdspm.c:5734 snd_hdspm_channel_info() warn: potential spectre issue 'hdspm->channel_map_in' (local cap)

This patch puts array_index_nospec() for hardening against them.

BugLink: https://marc.info/?l=linux-kernel&m=152411496503418&w=2
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
sound/pci/rme9652/hdspm.c