From 0b987032f8b58ef51cc8a042f46cc0cf1f277172 Mon Sep 17 00:00:00 2001
From: Jon Hunter <jonathanh@nvidia.com>
Date: Wed, 15 Jul 2020 12:38:42 +0100
Subject: [PATCH] usb: tegra: Fix allocation for the FPCI context
Git-commit: 0b987032f8b58ef51cc8a042f46cc0cf1f277172
Patch-mainline: v5.8-rc7
References: git-fixes
Commit 5c4e8d3781bc ("usb: host: xhci-tegra: Add support for XUSB
context save/restore") is using the IPFS 'num_offsets' value when
allocating memory for FPCI context instead of the FPCI 'num_offsets'.
After commit cad064f1bd52 ("devres: handle zero size in devm_kmalloc()")
was added system suspend started failing on Tegra186. The kernel log
showed that the Tegra XHCI driver was crashing on entry to suspend when
attempting the save the USB context. On Tegra186, the IPFS context has a
zero length but the FPCI content has a non-zero length, and because of
the bug in the Tegra XHCI driver we are incorrectly allocating a zero
length array for the FPCI context. The crash seen on entering suspend
when we attempt to save the FPCI context and following commit
cad064f1bd52 ("devres: handle zero size in devm_kmalloc()") this now
causes a NULL pointer deference when we access the memory. Fix this by
correcting the amount of memory we are allocating for FPCI contexts.
Cc: stable@vger.kernel.org
Fixes: 5c4e8d3781bc ("usb: host: xhci-tegra: Add support for XUSB context save/restore")
Signed-off-by: Jon Hunter <jonathanh@nvidia.com>
Acked-by: Thierry Reding <treding@nvidia.com>
Link: https://lore.kernel.org/r/20200715113842.30680-1-jonathanh@nvidia.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Takashi Iwai <tiwai@suse.de>
---
drivers/usb/host/xhci-tegra.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/drivers/usb/host/xhci-tegra.c b/drivers/usb/host/xhci-tegra.c
index 2eaf5c0af80c..ee6bf01775bb 100644
--- a/drivers/usb/host/xhci-tegra.c
+++ b/drivers/usb/host/xhci-tegra.c
@@ -856,7 +856,7 @@ static int tegra_xusb_init_context(struct tegra_xusb *tegra)
if (!tegra->context.ipfs)
return -ENOMEM;
- tegra->context.fpci = devm_kcalloc(tegra->dev, soc->ipfs.num_offsets,
+ tegra->context.fpci = devm_kcalloc(tegra->dev, soc->fpci.num_offsets,
sizeof(u32), GFP_KERNEL);
if (!tegra->context.fpci)
return -ENOMEM;
--
2.16.4