| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Message-Id: <1314469905-7058-34-git-send-email-kys@microsoft.com>
Date: Sat, 27 Aug 2011 11:31:33 -0700
From: "K. Y. Srinivasan" <kys@...rosoft.com>
To: gregkh@...e.de, linux-kernel@...r.kernel.org,
devel@...uxdriverproject.org, virtualization@...ts.osdl.org
Cc: "K. Y. Srinivasan" <kys@...rosoft.com>,
Haiyang Zhang <haiyangz@...rosoft.com>
Subject: [PATCH 34/46] Staging: hv: vmbus: Properly deal with de-registering channel callback
Ensure that we correctly handle racing invocations of the channel callback
when the channel is being closed. We do this using the channel's inbound_lock.
A side-effect of this strategy is that we avoid repeatedly picking up this lock
as we drain the inbound ring-buffer.
Signed-off-by: K. Y. Srinivasan <kys@...rosoft.com>
Signed-off-by: Haiyang Zhang <haiyangz@...rosoft.com>
---
drivers/staging/hv/channel.c | 20 +++++---------------
drivers/staging/hv/connection.c | 3 +++
drivers/staging/hv/netvsc.c | 3 ---
drivers/staging/hv/storvsc_drv.c | 3 ---
4 files changed, 8 insertions(+), 21 deletions(-)
diff --git a/drivers/staging/hv/channel.c b/drivers/staging/hv/channel.c
index ac92c1f..b6f3d38 100644
--- a/drivers/staging/hv/channel.c
+++ b/drivers/staging/hv/channel.c
@@ -513,9 +513,12 @@ void vmbus_close(struct vmbus_channel *channel)
{
struct vmbus_channel_close_channel *msg;
int ret;
+ unsigned long flags;
/* Stop callback and cancel the timer asap */
+ spin_lock_irqsave(&channel->inbound_lock, flags);
channel->onchannel_callback = NULL;
+ spin_unlock_irqrestore(&channel->inbound_lock, flags);
/* Send a closing message */
@@ -735,19 +738,15 @@ int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
u32 packetlen;
u32 userlen;
int ret;
- unsigned long flags;
*buffer_actual_len = 0;
*requestid = 0;
- spin_lock_irqsave(&channel->inbound_lock, flags);
ret = hv_ringbuffer_peek(&channel->inbound, &desc,
sizeof(struct vmpacket_descriptor));
- if (ret != 0) {
- spin_unlock_irqrestore(&channel->inbound_lock, flags);
+ if (ret != 0)
return 0;
- }
packetlen = desc.len8 << 3;
userlen = packetlen - (desc.offset8 << 3);
@@ -755,7 +754,6 @@ int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
*buffer_actual_len = userlen;
if (userlen > bufferlen) {
- spin_unlock_irqrestore(&channel->inbound_lock, flags);
pr_err("Buffer too small - got %d needs %d\n",
bufferlen, userlen);
@@ -768,7 +766,6 @@ int vmbus_recvpacket(struct vmbus_channel *channel, void *buffer,
ret = hv_ringbuffer_read(&channel->inbound, buffer, userlen,
(desc.offset8 << 3));
- spin_unlock_irqrestore(&channel->inbound_lock, flags);
return 0;
}
@@ -785,19 +782,15 @@ int vmbus_recvpacket_raw(struct vmbus_channel *channel, void *buffer,
u32 packetlen;
u32 userlen;
int ret;
- unsigned long flags;
*buffer_actual_len = 0;
*requestid = 0;
- spin_lock_irqsave(&channel->inbound_lock, flags);
ret = hv_ringbuffer_peek(&channel->inbound, &desc,
sizeof(struct vmpacket_descriptor));
- if (ret != 0) {
- spin_unlock_irqrestore(&channel->inbound_lock, flags);
+ if (ret != 0)
return 0;
- }
packetlen = desc.len8 << 3;
@@ -806,8 +799,6 @@ int vmbus_recvpacket_raw(struct vmbus_channel *channel, void *buffer,
*buffer_actual_len = packetlen;
if (packetlen > bufferlen) {
- spin_unlock_irqrestore(&channel->inbound_lock, flags);
-
pr_err("Buffer too small - needed %d bytes but "
"got space for only %d bytes\n",
packetlen, bufferlen);
@@ -819,7 +810,6 @@ int vmbus_recvpacket_raw(struct vmbus_channel *channel, void *buffer,
/* Copy over the entire packet to the user buffer */
ret = hv_ringbuffer_read(&channel->inbound, buffer, packetlen, 0);
- spin_unlock_irqrestore(&channel->inbound_lock, flags);
return 0;
}
EXPORT_SYMBOL_GPL(vmbus_recvpacket_raw);
diff --git a/drivers/staging/hv/connection.c b/drivers/staging/hv/connection.c
index 7a3ec75..6aab802 100644
--- a/drivers/staging/hv/connection.c
+++ b/drivers/staging/hv/connection.c
@@ -215,6 +215,7 @@ struct vmbus_channel *relid2channel(u32 relid)
static void process_chn_event(u32 relid)
{
struct vmbus_channel *channel;
+ unsigned long flags;
/*
* Find the channel based on this relid and invokes the
@@ -222,11 +223,13 @@ static void process_chn_event(u32 relid)
*/
channel = relid2channel(relid);
+ spin_lock_irqsave(&channel->inbound_lock, flags);
if (channel && (channel->onchannel_callback != NULL)) {
channel->onchannel_callback(channel->channel_callback_context);
} else {
pr_err("channel not found for relid - %u\n", relid);
}
+ spin_unlock_irqrestore(&channel->inbound_lock, flags);
}
/*
diff --git a/drivers/staging/hv/netvsc.c b/drivers/staging/hv/netvsc.c
index 9828f0b..e4cc40a 100644
--- a/drivers/staging/hv/netvsc.c
+++ b/drivers/staging/hv/netvsc.c
@@ -62,9 +62,7 @@ static struct netvsc_device *get_outbound_net_device(struct hv_device *device)
static struct netvsc_device *get_inbound_net_device(struct hv_device *device)
{
struct netvsc_device *net_device;
- unsigned long flags;
- spin_lock_irqsave(&device->channel->inbound_lock, flags);
net_device = device->ext;
if (!net_device)
@@ -75,7 +73,6 @@ static struct netvsc_device *get_inbound_net_device(struct hv_device *device)
net_device = NULL;
get_in_err:
- spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
return net_device;
}
diff --git a/drivers/staging/hv/storvsc_drv.c b/drivers/staging/hv/storvsc_drv.c
index d575bc9..3686d10 100644
--- a/drivers/staging/hv/storvsc_drv.c
+++ b/drivers/staging/hv/storvsc_drv.c
@@ -352,9 +352,7 @@ static inline struct storvsc_device *get_in_stor_device(
struct hv_device *device)
{
struct storvsc_device *stor_device;
- unsigned long flags;
- spin_lock_irqsave(&device->channel->inbound_lock, flags);
stor_device = (struct storvsc_device *)device->ext;
if (!stor_device)
@@ -370,7 +368,6 @@ static inline struct storvsc_device *get_in_stor_device(
stor_device = NULL;
get_in_err:
- spin_unlock_irqrestore(&device->channel->inbound_lock, flags);
return stor_device;
}
--
1.7.4.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists