From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Date: Wed, 20 Jan 2021 11:03:03 +0000 (+0100)
Subject: 5.4-stable patches
X-Git-Tag: v4.4.253~27
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=9814dd3ddf758e2f4c0b10e6db55fb26d6a5bbf6;p=thirdparty%2Fkernel%2Fstable-queue.git

5.4-stable patches

added patches:
	xen-privcmd-allow-fetching-resource-sizes.patch
---

diff --git a/queue-5.4/series b/queue-5.4/series
index ab3c52acd07..f58353f4bdc 100644
--- a/queue-5.4/series
+++ b/queue-5.4/series
@@ -1,2 +1,3 @@
 usb-ohci-make-distrust_firmware-param-default-to-false.patch
 compiler.h-raise-minimum-version-of-gcc-to-5.1-for-arm64.patch
+xen-privcmd-allow-fetching-resource-sizes.patch
diff --git a/queue-5.4/xen-privcmd-allow-fetching-resource-sizes.patch b/queue-5.4/xen-privcmd-allow-fetching-resource-sizes.patch
new file mode 100644
index 00000000000..3c19adb8db2
--- /dev/null
+++ b/queue-5.4/xen-privcmd-allow-fetching-resource-sizes.patch
@@ -0,0 +1,86 @@
+From ef3a575baf53571dc405ee4028e26f50856898e7 Mon Sep 17 00:00:00 2001
+From: Roger Pau Monne <roger.pau@citrix.com>
+Date: Tue, 12 Jan 2021 12:53:58 +0100
+Subject: xen/privcmd: allow fetching resource sizes
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+From: Roger Pau Monne <roger.pau@citrix.com>
+
+commit ef3a575baf53571dc405ee4028e26f50856898e7 upstream.
+
+Allow issuing an IOCTL_PRIVCMD_MMAP_RESOURCE ioctl with num = 0 and
+addr = 0 in order to fetch the size of a specific resource.
+
+Add a shortcut to the default map resource path, since fetching the
+size requires no address to be passed in, and thus no VMA to setup.
+
+This is missing from the initial implementation, and causes issues
+when mapping resources that don't have fixed or known sizes.
+
+Signed-off-by: Roger Pau Monné <roger.pau@citrix.com>
+Reviewed-by: Juergen Gross <jgross@suse.com>
+Tested-by: Andrew Cooper <andrew.cooper3@citrix.com>
+Cc: stable@vger.kernel.org # >= 4.18
+Link: https://lore.kernel.org/r/20210112115358.23346-1-roger.pau@citrix.com
+Signed-off-by: Juergen Gross <jgross@suse.com>
+Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
+---
+ drivers/xen/privcmd.c |   25 +++++++++++++++++++------
+ 1 file changed, 19 insertions(+), 6 deletions(-)
+
+--- a/drivers/xen/privcmd.c
++++ b/drivers/xen/privcmd.c
+@@ -724,14 +724,15 @@ static long privcmd_ioctl_restrict(struc
+ 	return 0;
+ }
+ 
+-static long privcmd_ioctl_mmap_resource(struct file *file, void __user *udata)
++static long privcmd_ioctl_mmap_resource(struct file *file,
++				struct privcmd_mmap_resource __user *udata)
+ {
+ 	struct privcmd_data *data = file->private_data;
+ 	struct mm_struct *mm = current->mm;
+ 	struct vm_area_struct *vma;
+ 	struct privcmd_mmap_resource kdata;
+ 	xen_pfn_t *pfns = NULL;
+-	struct xen_mem_acquire_resource xdata;
++	struct xen_mem_acquire_resource xdata = { };
+ 	int rc;
+ 
+ 	if (copy_from_user(&kdata, udata, sizeof(kdata)))
+@@ -741,6 +742,22 @@ static long privcmd_ioctl_mmap_resource(
+ 	if (data->domid != DOMID_INVALID && data->domid != kdata.dom)
+ 		return -EPERM;
+ 
++	/* Both fields must be set or unset */
++	if (!!kdata.addr != !!kdata.num)
++		return -EINVAL;
++
++	xdata.domid = kdata.dom;
++	xdata.type = kdata.type;
++	xdata.id = kdata.id;
++
++	if (!kdata.addr && !kdata.num) {
++		/* Query the size of the resource. */
++		rc = HYPERVISOR_memory_op(XENMEM_acquire_resource, &xdata);
++		if (rc)
++			return rc;
++		return __put_user(xdata.nr_frames, &udata->num);
++	}
++
+ 	down_write(&mm->mmap_sem);
+ 
+ 	vma = find_vma(mm, kdata.addr);
+@@ -775,10 +792,6 @@ static long privcmd_ioctl_mmap_resource(
+ 	} else
+ 		vma->vm_private_data = PRIV_VMA_LOCKED;
+ 
+-	memset(&xdata, 0, sizeof(xdata));
+-	xdata.domid = kdata.dom;
+-	xdata.type = kdata.type;
+-	xdata.id = kdata.id;
+ 	xdata.frame = kdata.idx;
+ 	xdata.nr_frames = kdata.num;
+ 	set_xen_guest_handle(xdata.frame_list, pfns);