This is a note to let you know that I've just added the patch titled
xen: Prevent buffer overflow in privcmd ioctl
to the 5.0-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
xen-prevent-buffer-overflow-in-privcmd-ioctl.patch
and it can be found in the queue-5.0 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 42d8644bd77dd2d747e004e367cb0c895a606f39 Mon Sep 17 00:00:00 2001
From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Date: Thu, 4 Apr 2019 18:12:17 +0300
Subject: xen: Prevent buffer overflow in privcmd ioctl
From: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
commit 42d8644bd77dd2d747e004e367cb0c895a606f39 upstream.
The "call" variable comes from the user in privcmd_ioctl_hypercall().
It's an offset into the hypercall_page[] which has (PAGE_SIZE / 32)
elements. We need to put an upper bound on it to prevent an out of
bounds access.
Cc: stable@xxxxxxxxxxxxxxx
Fixes: 1246ae0bb992 ("xen: add variable hypercall caller")
Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Reviewed-by: Boris Ostrovsky <boris.ostrovsky@xxxxxxxxxx>
Signed-off-by: Juergen Gross <jgross@xxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
arch/x86/include/asm/xen/hypercall.h | 3 +++
1 file changed, 3 insertions(+)
--- a/arch/x86/include/asm/xen/hypercall.h
+++ b/arch/x86/include/asm/xen/hypercall.h
@@ -206,6 +206,9 @@ xen_single_call(unsigned int call,
__HYPERCALL_DECLS;
__HYPERCALL_5ARG(a1, a2, a3, a4, a5);
+ if (call >= PAGE_SIZE / sizeof(hypercall_page[0]))
+ return -EINVAL;
+
asm volatile(CALL_NOSPEC
: __HYPERCALL_5PARAM
: [thunk_target] "a" (&hypercall_page[call])
Patches currently in stable-queue which might be from dan.carpenter@xxxxxxxxxx are
queue-5.0/netfilter-nf_tables-use-after-free-in-dynamic-operat.patch
queue-5.0/xen-prevent-buffer-overflow-in-privcmd-ioctl.patch
