linux-kernel - [PATCH 4.19 19/56] drm/amdgpu: Prevent kernel-infoleak in amdgpu_info

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:   Mon,  3 Aug 2020 14:19:34 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     linux-kernel@...r.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@...uxfoundation.org>,
        stable@...r.kernel.org, Dan Carpenter <dan.carpenter@...cle.com>,
        Christian König <christian.koenig@....com>,
        Peilin Ye <yepeilin.cs@...il.com>,
        Alex Deucher <alexander.deucher@....com>
Subject: [PATCH 4.19 19/56] drm/amdgpu: Prevent kernel-infoleak in amdgpu_info_ioctl()

From: Peilin Ye <yepeilin.cs@...il.com>

commit 543e8669ed9bfb30545fd52bc0e047ca4df7fb31 upstream.

Compiler leaves a 4-byte hole near the end of `dev_info`, causing
amdgpu_info_ioctl() to copy uninitialized kernel stack memory to userspace
when `size` is greater than 356.

In 2015 we tried to fix this issue by doing `= {};` on `dev_info`, which
unfortunately does not initialize that 4-byte hole. Fix it by using
memset() instead.

Cc: stable@...r.kernel.org
Fixes: c193fa91b918 ("drm/amdgpu: information leak in amdgpu_info_ioctl()")
Fixes: d38ceaf99ed0 ("drm/amdgpu: add core driver (v4)")
Suggested-by: Dan Carpenter <dan.carpenter@...cle.com>
Reviewed-by: Christian König <christian.koenig@....com>
Signed-off-by: Peilin Ye <yepeilin.cs@...il.com>
Signed-off-by: Alex Deucher <alexander.deucher@....com>
Signed-off-by: Greg Kroah-Hartman <gregkh@...uxfoundation.org>

---
 drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
@@ -549,9 +549,10 @@ static int amdgpu_info_ioctl(struct drm_
 		return n ? -EFAULT : 0;
 	}
 	case AMDGPU_INFO_DEV_INFO: {
-		struct drm_amdgpu_info_device dev_info = {};
+		struct drm_amdgpu_info_device dev_info;
 		uint64_t vm_size;
 
+		memset(&dev_info, 0, sizeof(dev_info));
 		dev_info.device_id = dev->pdev->device;
 		dev_info.chip_rev = adev->rev_id;
 		dev_info.external_rev = adev->external_rev_id;