linux-kernel - [PATCH] vTPM: fix memory allocation flag for rtce buffer at kernel boot

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 for Android: free password hash cracker in your pocket

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Wed,  7 Oct 2015 20:10:02 -0400
From:	"Hon Ching(Vicky) Lo" <honclo@...ux.vnet.ibm.com>
To:	lo1@...ibm.com
Cc:	linux-kernel@...r.kernel.org,
	"Hon Ching(Vicky) Lo" <honclo@...ux.vnet.ibm.com>
Subject: [PATCH] vTPM: fix memory allocation flag for rtce buffer at kernel boot

At ibm vtpm initialzation, tpm_ibmvtpm_probe() registers its interrupt
handler, ibmvtpm_interrupt, which calls ibmvtpm_crq_process to allocate
memory for rtce buffer.  The current code uses 'GFP_KERNEL' as the
type of kernel memory allocation, which resulted a warning at
kernel/lockdep.c.  This patch uses 'GFP_ATOMIC' instead so that the
allocation is high-priority and does not sleep.

Signed-off-by: Hon Ching(Vicky) Lo <honclo@...ux.vnet.ibm.com>
---
 drivers/char/tpm/tpm_ibmvtpm.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/drivers/char/tpm/tpm_ibmvtpm.c b/drivers/char/tpm/tpm_ibmvtpm.c
index 27ebf95..3e6a226 100644
--- a/drivers/char/tpm/tpm_ibmvtpm.c
+++ b/drivers/char/tpm/tpm_ibmvtpm.c
@@ -491,7 +491,7 @@ static void ibmvtpm_crq_process(struct ibmvtpm_crq *crq,
 			}
 			ibmvtpm->rtce_size = be16_to_cpu(crq->len);
 			ibmvtpm->rtce_buf = kmalloc(ibmvtpm->rtce_size,
-						    GFP_KERNEL);
+						    GFP_ATOMIC);
 			if (!ibmvtpm->rtce_buf) {
 				dev_err(ibmvtpm->dev, "Failed to allocate memory for rtce buffer\n");
 				return;
-- 
1.7.1

--
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/