This is a note to let you know that I've just added the patch titled
soc: aspeed: lpc-ctrl: Fix boundary check for mmap
to the 5.4-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:
soc-aspeed-lpc-ctrl-fix-boundary-check-for-mmap.patch
and it can be found in the queue-5.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From b49a0e69a7b1a68c8d3f64097d06dabb770fec96 Mon Sep 17 00:00:00 2001
From: Iwona Winiarska <iwona.winiarska@xxxxxxxxx>
Date: Wed, 4 Aug 2021 01:48:18 +0200
Subject: soc: aspeed: lpc-ctrl: Fix boundary check for mmap
From: Iwona Winiarska <iwona.winiarska@xxxxxxxxx>
commit b49a0e69a7b1a68c8d3f64097d06dabb770fec96 upstream.
The check mixes pages (vm_pgoff) with bytes (vm_start, vm_end) on one
side of the comparison, and uses resource address (rather than just the
resource size) on the other side of the comparison.
This can allow malicious userspace to easily bypass the boundary check and
map pages that are located outside memory-region reserved by the driver.
Fixes: 6c4e97678501 ("drivers/misc: Add Aspeed LPC control driver")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Iwona Winiarska <iwona.winiarska@xxxxxxxxx>
Reviewed-by: Andrew Jeffery <andrew@xxxxxxxx>
Tested-by: Andrew Jeffery <andrew@xxxxxxxx>
Reviewed-by: Joel Stanley <joel@xxxxxxxx>
Signed-off-by: Joel Stanley <joel@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/soc/aspeed/aspeed-lpc-ctrl.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/drivers/soc/aspeed/aspeed-lpc-ctrl.c
+++ b/drivers/soc/aspeed/aspeed-lpc-ctrl.c
@@ -46,7 +46,7 @@ static int aspeed_lpc_ctrl_mmap(struct f
unsigned long vsize = vma->vm_end - vma->vm_start;
pgprot_t prot = vma->vm_page_prot;
- if (vma->vm_pgoff + vsize > lpc_ctrl->mem_base + lpc_ctrl->mem_size)
+ if (vma->vm_pgoff + vma_pages(vma) > lpc_ctrl->mem_size >> PAGE_SHIFT)
return -EINVAL;
/* ast2400/2500 AHB accesses are not cache coherent */
Patches currently in stable-queue which might be from iwona.winiarska@xxxxxxxxx are
queue-5.4/soc-aspeed-lpc-ctrl-fix-boundary-check-for-mmap.patch
queue-5.4/soc-aspeed-p2a-ctrl-fix-boundary-check-for-mmap.patch
