linux-kernel - [v2 2/2] vfio iommu type1: fix the testing of capability for remote task

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

Date:   Thu, 12 Jan 2017 16:52:03 +0800
From:   Jike Song <jike.song@...el.com>
To:     alex.williamson@...hat.com, serge@...lyn.com
Cc:     kwankhede@...dia.com, kraxel@...hat.com,
        linux-security-module@...r.kernel.org, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org, Jike Song <jike.song@...el.com>
Subject: [v2 2/2] vfio iommu type1: fix the testing of capability for remote task

Before the mdev enhancement type1 iommu used capable() to test the
capability of current task; in the course of mdev development a
new requirement, testing for another task other than current, was
raised.  ns_capable() was used for this purpose, however it still
tests current, the only difference is, in a specified namespace.

Fix it by using has_capability() instead, which tests the cap for
specified task in init_user_ns, the same namespace as capable().

Cc: Alex Williamson <alex.williamson@...hat.com>
Cc: Kirti Wankhede <kwankhede@...dia.com>
Cc: Gerd Hoffmann <kraxel@...hat.com>
Signed-off-by: Jike Song <jike.song@...el.com>
---
 drivers/vfio/vfio_iommu_type1.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index 9266271..77373e5 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -495,8 +495,7 @@ static int vfio_pin_page_external(struct vfio_dma *dma, unsigned long vaddr,
 				  unsigned long *pfn_base, bool do_accounting)
 {
 	unsigned long limit;
-	bool lock_cap = ns_capable(task_active_pid_ns(dma->task)->user_ns,
-				   CAP_IPC_LOCK);
+	bool lock_cap = has_capability(dma->task, CAP_IPC_LOCK);
 	struct mm_struct *mm;
 	int ret;
 	bool rsvd;
-- 
1.9.3