This is a note to let you know that I've just added the patch titled
IB/ucm: Fix Spectre v1 vulnerability
to the 4.4-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:
ib-ucm-fix-spectre-v1-vulnerability.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 0295e39595e1146522f2722715dba7f7fba42217 Mon Sep 17 00:00:00 2001
From: "Gustavo A. R. Silva" <gustavo@xxxxxxxxxxxxxx>
Date: Tue, 16 Oct 2018 16:32:40 +0200
Subject: IB/ucm: Fix Spectre v1 vulnerability
From: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
commit 0295e39595e1146522f2722715dba7f7fba42217 upstream.
hdr.cmd can be indirectly controlled by user-space, hence leading to
a potential exploitation of the Spectre variant 1 vulnerability.
This issue was detected with the help of Smatch:
drivers/infiniband/core/ucm.c:1127 ib_ucm_write() warn: potential
spectre issue 'ucm_cmd_table' [r] (local cap)
Fix this by sanitizing hdr.cmd before using it to index
ucm_cmd_table.
Notice that given that speculation windows are large, the policy is
to kill the speculation on the first load and not worry if it can be
completed with a dependent load/store [1].
[1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Gustavo A. R. Silva <gustavo@xxxxxxxxxxxxxx>
Signed-off-by: Doug Ledford <dledford@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/infiniband/core/ucm.c | 3 +++
1 file changed, 3 insertions(+)
--- a/drivers/infiniband/core/ucm.c
+++ b/drivers/infiniband/core/ucm.c
@@ -46,6 +46,8 @@
#include <linux/mutex.h>
#include <linux/slab.h>
+#include <linux/nospec.h>
+
#include <asm/uaccess.h>
#include <rdma/ib.h>
@@ -1115,6 +1117,7 @@ static ssize_t ib_ucm_write(struct file
if (hdr.cmd >= ARRAY_SIZE(ucm_cmd_table))
return -EINVAL;
+ hdr.cmd = array_index_nospec(hdr.cmd, ARRAY_SIZE(ucm_cmd_table));
if (hdr.in + sizeof(hdr) > len)
return -EINVAL;
Patches currently in stable-queue which might be from gustavo@xxxxxxxxxxxxxx are
queue-4.4/video-fbdev-pxa3xx_gcu-fix-error-return-code-in-pxa3.patch
queue-4.4/spi-bcm63xx-fix-error-return-code-in-bcm63xx_spi_pro.patch
queue-4.4/usb-imx21-hcd-fix-error-return-code-in-imx21_probe.patch
queue-4.4/spi-xlp-fix-error-return-code-in-xlp_spi_probe.patch
queue-4.4/gpio-msic-fix-error-return-code-in-platform_msic_gpi.patch
queue-4.4/usb-ehci-omap-fix-error-return-code-in-ehci_hcd_omap.patch
queue-4.4/gpu-host1x-fix-error-return-code-in-host1x_probe.patch
queue-4.4/ptp-fix-spectre-v1-vulnerability.patch
queue-4.4/tty-serial-sprd-fix-error-return-code-in-sprd_probe.patch
queue-4.4/rdma-ucma-fix-spectre-v1-vulnerability.patch
queue-4.4/usb-gadget-storage-fix-spectre-v1-vulnerability.patch
queue-4.4/ib-ucm-fix-spectre-v1-vulnerability.patch
queue-4.4/usb-dwc3-omap-fix-error-return-code-in-dwc3_omap_pro.patch
queue-4.4/spi-bcm63xx-hspi-fix-error-return-code-in-bcm63xx_hs.patch
