Commit 0fb10476 authored Sep 17, 2021 by Jan Beulich Committed by Greg Kroah-Hartman Nov 03, 2022

Xen/gntdev: don't ignore kernel unmapping error



commit f28347cc66395e96712f5c2db0a302ee75bafce6 upstream.

While working on XSA-361 and its follow-ups, I failed to spot another
place where the kernel mapping part of an operation was not treated the
same as the user space part. Detect and propagate errors and add a 2nd
pr_debug().

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Reviewed-by: Juergen Gross <jgross@suse.com>
Link: https://lore.kernel.org/r/c2513395-74dc-aea3-9192-fd265aa44e35@suse.com


Signed-off-by: Juergen Gross <jgross@suse.com>
Signed-off-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Co-authored-by: Demi Marie Obenour <demi@invisiblethingslab.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

parent c6ca9cc3

drivers/xen/gntdev.c

+8 −0

Original line number	Diff line number	Diff line
		@@ -396,6 +396,14 @@ static void __unmap_grant_pages_done(int result,
		map->unmap_ops[offset+i].handle,
		map->unmap_ops[offset+i].status);
		map->unmap_ops[offset+i].handle = -1;
		if (use_ptemod) {
		WARN_ON(map->kunmap_ops[offset+i].status &&
		map->kunmap_ops[offset+i].handle != -1);
		pr_debug("kunmap handle=%u st=%d\n",
		map->kunmap_ops[offset+i].handle,
		map->kunmap_ops[offset+i].status);
		map->kunmap_ops[offset+i].handle = -1;
		}
		}
		/*
		* Decrease the live-grant counter. This must happen after the loop to