Re: boot failure with 4.13.0-rc6 due to ATA errors

Christoph Hellwig
2017-08-29T12:42:11Z

On Mon, Aug 28, 2017 at 02:22:25PM -0700, Tejun Heo wrote:
> Hello,
>
> On Mon, Aug 28, 2017 at 02:26:52PM -0600, David Ahern wrote:
> > On 8/28/17 1:59 PM, Tejun Heo wrote:
> > > Can you please verify whether 818831c8b22f ("libata: implement
> > > SECURITY PROTOCOL IN/OUT") is the culprit? ie. try to boot the commit
> > > to verify that the problem is there, and try the one prior?
> >
> > That commit is the problem. a0fd2454a36ffab2ce39b3a91c1385a5f98e63f0
> > works fine.
>
> Christoph, is there anything we can do to further gate issuing of the
> offending command? Otherwise, we might have to go for whitelist
> instead.

We could try to check the IDENTIFY DEVICE word, but given that it has
a dual meaning in older spec versions I don't really like the idea
either. Untested patch below as I'm not near my OPAL capable drive.

Also most recent ATA features seem to be keyed off a log page of some
sort, so we'll run into more problems like this.

---
>From e661047ec3a25587648b07c02a687a7dac778f3b Mon Sep 17 00:00:00 2001
From: Christoph Hellwig <hch@lst.de>
Date: Tue, 29 Aug 2017 14:35:50 +0200
Subject: libata: check for trusted computing in IDENTIFY DEVICE data

ATA-8 and later mirrors the TRUSTED COMPUTING SUPPORTED bit in word 48 of
the IDENTIFY DEVICE data. Check this before issuing a READ LOG PAGE
command to avoid issues with buggy devices. The only downside is that
we can't support Security Send / Receive for a device with an older
revision due to the conflicting use of this field in earlier
specifications.

Signed-off-by: Christoph Hellwig <hch@lst.de>
---
drivers/ata/libata-core.c | 3 +++
include/linux/ata.h | 10 +++++++++-
2 files changed, 12 insertions(+), 1 deletion(-)

diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 697f5f896b19..ca57b03ab950 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -2413,6 +2413,9 @@ static void ata_dev_config_trusted(struct ata_device *dev)
u64 trusted_cap;
unsigned int err;

+ if (!ata_id_has_trusted(dev->id))
+ return;
+
if (!ata_identify_page_supported(dev, ATA_LOG_SECURITY)) {
ata_dev_warn(dev,
"Security Log not supported\n");
diff --git a/include/linux/ata.h b/include/linux/ata.h
index e65ae4b2ed48..c7a353825450 100644
--- a/include/linux/ata.h
+++ b/include/linux/ata.h
@@ -60,7 +60,8 @@ enum {
ATA_ID_FW_REV = 23,
ATA_ID_PROD = 27,
ATA_ID_MAX_MULTSECT = 47,
- ATA_ID_DWORD_IO = 48,
+ ATA_ID_DWORD_IO = 48, /* before ATA-8 */
+ ATA_ID_TRUSTED = 48, /* ATA-8 and later */
ATA_ID_CAPABILITY = 49,
ATA_ID_OLD_PIO_MODES = 51,
ATA_ID_OLD_DMA_MODES = 52,
@@ -889,6 +890,13 @@ static inline bool ata_id_has_dword_io(const u16 *id)
return id[ATA_ID_DWORD_IO] & (1 << 0);
}

+static inline bool ata_id_has_trusted(const u16 *id)
+{
+ if (ata_id_major_version(id) <= 7)
+ return false;
+ return id[ATA_ID_TRUSTED] & (1 << 0);
+}
+
static inline bool ata_id_has_unload(const u16 *id)
{
if (ata_id_major_version(id) >= 7 &&
--
2.11.0