[PATCH 6.8 003/172] ata: libata-scsi: Fix ata_scsi_dev_rescan() error path

Greg Kroah-Hartman
2024-04-15T14:23:53Z

From: Damien Le Moal <dlemoal@kernel.org>

commit 79336504781e7fee5ddaf046dcc186c8dfdf60b1 upstream.

Commit 0c76106cb975 ("scsi: sd: Fix TCG OPAL unlock on system resume")
incorrectly handles failures of scsi_resume_device() in
ata_scsi_dev_rescan(), leading to a double call to
spin_unlock_irqrestore() to unlock a device port. Fix this by redefining
the goto labels used in case of errors and only unlock the port
scsi_scan_mutex when scsi_resume_device() fails.

Bug found with the Smatch static checker warning:

drivers/ata/libata-scsi.c:4774 ata_scsi_dev_rescan()
error: double unlocked 'ap->lock' (orig line 4757)

Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Fixes: 0c76106cb975 ("scsi: sd: Fix TCG OPAL unlock on system resume")
Cc: stable@vger.kernel.org
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Niklas Cassel <cassel@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/ata/libata-scsi.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

--- a/drivers/ata/libata-scsi.c
+++ b/drivers/ata/libata-scsi.c
@@ -4745,7 +4745,7 @@ void ata_scsi_dev_rescan(struct work_str
* bail out.
*/
if (ap->pflags & ATA_PFLAG_SUSPENDED)
- goto unlock;
+ goto unlock_ap;

if (!sdev)
continue;
@@ -4758,7 +4758,7 @@ void ata_scsi_dev_rescan(struct work_str
if (do_resume) {
ret = scsi_resume_device(sdev);
if (ret == -EWOULDBLOCK)
- goto unlock;
+ goto unlock_scan;
dev->flags &= ~ATA_DFLAG_RESUMING;
}
ret = scsi_rescan_device(sdev);
@@ -4766,12 +4766,13 @@ void ata_scsi_dev_rescan(struct work_str
spin_lock_irqsave(ap->lock, flags);

if (ret)
- goto unlock;
+ goto unlock_ap;
}
}

-unlock:
+unlock_ap:
spin_unlock_irqrestore(ap->lock, flags);
+unlock_scan:
mutex_unlock(&ap->scsi_scan_mutex);

/* Reschedule with a delay if scsi_rescan_device() returned an error */