This is a note to let you know that I've just added the patch titled
[media] saa7164: fix double fetch PCIe access condition
to the 4.12-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:
saa7164-fix-double-fetch-pcie-access-condition.patch
and it can be found in the queue-4.12 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 6fb05e0dd32e566facb96ea61a48c7488daa5ac3 Mon Sep 17 00:00:00 2001
From: Steven Toth <stoth@xxxxxxxxxxxxxx>
Date: Tue, 6 Jun 2017 09:30:27 -0300
Subject: [media] saa7164: fix double fetch PCIe access condition
From: Steven Toth <stoth@xxxxxxxxxxxxxx>
commit 6fb05e0dd32e566facb96ea61a48c7488daa5ac3 upstream.
Avoid a double fetch by reusing the values from the prior transfer.
Originally reported via https://bugzilla.kernel.org/show_bug.cgi?id=195559
Thanks to Pengfei Wang <wpengfeinudt@xxxxxxxxx> for reporting.
Signed-off-by: Steven Toth <stoth@xxxxxxxxxxxxxx>
Reported-by: Pengfei Wang <wpengfeinudt@xxxxxxxxx>
Signed-off-by: Mauro Carvalho Chehab <mchehab@xxxxxxxxxxxxxxxx>
Cc: Eduardo Valentin <eduval@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
drivers/media/pci/saa7164/saa7164-bus.c | 13 +------------
1 file changed, 1 insertion(+), 12 deletions(-)
--- a/drivers/media/pci/saa7164/saa7164-bus.c
+++ b/drivers/media/pci/saa7164/saa7164-bus.c
@@ -389,11 +389,11 @@ int saa7164_bus_get(struct saa7164_dev *
msg_tmp.size = le16_to_cpu((__force __le16)msg_tmp.size);
msg_tmp.command = le32_to_cpu((__force __le32)msg_tmp.command);
msg_tmp.controlselector = le16_to_cpu((__force __le16)msg_tmp.controlselector);
+ memcpy(msg, &msg_tmp, sizeof(*msg));
/* No need to update the read positions, because this was a peek */
/* If the caller specifically want to peek, return */
if (peekonly) {
- memcpy(msg, &msg_tmp, sizeof(*msg));
goto peekout;
}
@@ -438,21 +438,15 @@ int saa7164_bus_get(struct saa7164_dev *
space_rem = bus->m_dwSizeGetRing - curr_grp;
if (space_rem < sizeof(*msg)) {
- /* msg wraps around the ring */
- memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, space_rem);
- memcpy_fromio((u8 *)msg + space_rem, bus->m_pdwGetRing,
- sizeof(*msg) - space_rem);
if (buf)
memcpy_fromio(buf, bus->m_pdwGetRing + sizeof(*msg) -
space_rem, buf_size);
} else if (space_rem == sizeof(*msg)) {
- memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg));
if (buf)
memcpy_fromio(buf, bus->m_pdwGetRing, buf_size);
} else {
/* Additional data wraps around the ring */
- memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg));
if (buf) {
memcpy_fromio(buf, bus->m_pdwGetRing + curr_grp +
sizeof(*msg), space_rem - sizeof(*msg));
@@ -465,15 +459,10 @@ int saa7164_bus_get(struct saa7164_dev *
} else {
/* No wrapping */
- memcpy_fromio(msg, bus->m_pdwGetRing + curr_grp, sizeof(*msg));
if (buf)
memcpy_fromio(buf, bus->m_pdwGetRing + curr_grp + sizeof(*msg),
buf_size);
}
- /* Convert from little endian to CPU */
- msg->size = le16_to_cpu((__force __le16)msg->size);
- msg->command = le32_to_cpu((__force __le32)msg->command);
- msg->controlselector = le16_to_cpu((__force __le16)msg->controlselector);
/* Update the read positions, adjusting the ring */
saa7164_writel(bus->m_dwGetReadPos, new_grp);
Patches currently in stable-queue which might be from stoth@xxxxxxxxxxxxxx are
queue-4.12/saa7164-fix-double-fetch-pcie-access-condition.patch