lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [thread-next>] [day] [month] [year] [list]
Date:	Sun,  8 Nov 2015 09:51:07 +0200
From:	Jarkko Sakkinen <jarkko.sakkinen@...ux.intel.com>
To:	Peter Huewe <peterhuewe@....de>,
	Marcel Selhorst <tpmdd@...horst.net>
Cc:	Jarkko Sakkinen <jarkko.sakkinen@...ux.intel.com>,
	Jason Gunthorpe <jgunthorpe@...idianresearch.com>,
	tpmdd-devel@...ts.sourceforge.net (moderated list:TPM DEVICE DRIVER),
	linux-kernel@...r.kernel.org (open list)
Subject: [PATCH] tpm: fix compat 'ppi' link handling in tpm_chip_register()

__compat_only_sysfs_link_entry_to_kobj() was unconditionally called for
TPM1 chips, which caused crash on Acer C720 laptop where DSM for the
ACPI object did not exist.

There are two reasons for unwanted behavior:

* The code did not check whether
  __compat_only_sysfs_link_entry_to_kobj() returned -ENOENT. This is
  OK. It just meanst that ppi is not available.
* The code did not clean up properly. Compat link should added only
  after all other init is done.

This patch sorts out these issues.

Fixes: 9b774d5cf2db
Reported-by: Jeremiah Mahler <jmmahler@...il.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@...ux.intel.com>
Tested-by: Jeremiah Mahler <jmmahler@...il.com>
---
 drivers/char/tpm/tpm-chip.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c
index a5cdce7..45cc39a 100644
--- a/drivers/char/tpm/tpm-chip.c
+++ b/drivers/char/tpm/tpm-chip.c
@@ -226,14 +226,6 @@ int tpm_chip_register(struct tpm_chip *chip)
 	if (rc)
 		goto out_err;
 
-	if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
-		rc = __compat_only_sysfs_link_entry_to_kobj(&chip->pdev->kobj,
-							    &chip->dev.kobj,
-							    "ppi");
-		if (rc)
-			goto out_err;
-	}
-
 	/* Make the chip available. */
 	spin_lock(&driver_lock);
 	list_add_tail_rcu(&chip->list, &tpm_chip_list);
@@ -241,6 +233,16 @@ int tpm_chip_register(struct tpm_chip *chip)
 
 	chip->flags |= TPM_CHIP_FLAG_REGISTERED;
 
+	if (!(chip->flags & TPM_CHIP_FLAG_TPM2)) {
+		rc = __compat_only_sysfs_link_entry_to_kobj(&chip->pdev->kobj,
+							    &chip->dev.kobj,
+							    "ppi");
+		if (rc && rc != -ENOENT) {
+			tpm_chip_unregister(chip);
+			return rc;
+		}
+	}
+
 	return 0;
 out_err:
 	tpm1_chip_unregister(chip);
-- 
2.5.0

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Powered by blists - more mailing lists