[070/141] xhci: fix list access before init

Steven Rostedt
2013-07-03T18:41:52Z

[-- Attachment #1: 0070-xhci-fix-list-access-before-init.patch --]
[-- Type: text/plain, Size: 1624 bytes --]

3.6.11.6 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Vladimir Murzin <murzin.v@gmail.com>

[ Upstream commit 88696ae432ce7321540ac53d9caab3de9118b094 ]

If for whatever reason we fall into fail path in xhci_mem_init()
before bw table gets initialized we may access the uninitialized lists
in xhci_mem_cleanup().

Check for bw table before traversing lists in cleanup routine.

This patch should be backported to kernels as old as 3.2, that contain
the commit 839c817ce67178ca3c7c7ad534c571bba1e69ebe "xhci: Store
information about roothubs and TTs."

Reported-by: Sergey Dyasly <dserrg@gmail.com>
Tested-by: Sergey Dyasly <dserrg@gmail.com>
Signed-off-by: Vladimir Murzin <murzin.v@gmail.com>
Signed-off-by: Sarah Sharp <sarah.a.sharp@linux.intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
drivers/usb/host/xhci-mem.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/usb/host/xhci-mem.c b/drivers/usb/host/xhci-mem.c
index 0550d53..419d34a 100644
--- a/drivers/usb/host/xhci-mem.c
+++ b/drivers/usb/host/xhci-mem.c
@@ -1840,6 +1840,9 @@ void xhci_mem_cleanup(struct xhci_hcd *xhci)
}
spin_unlock_irqrestore(&xhci->lock, flags);

+ if (!xhci->rh_bw)
+ goto no_bw;
+
num_ports = HCS_MAX_PORTS(xhci->hcs_params1);
for (i = 0; i < num_ports; i++) {
struct xhci_interval_bw_table *bwt = &xhci->rh_bw[i].bw_table;
@@ -1858,6 +1861,7 @@ void xhci_mem_cleanup(struct xhci_hcd *xhci)
}
}

+no_bw:
xhci->num_usb2_ports = 0;
xhci->num_usb3_ports = 0;
xhci->num_active_eps = 0;
--
1.7.10.4