From: Stefan Priebe <s.priebe@profihost.ag>
To: qemu-devel@nongnu.org
Cc: Stefan Priebe <s.priebe@profihost.ag>
Subject: [Qemu-devel] [PATCH] PATCH V2: fix NULL dereferences / races between task completition and abort
Date: Wed, 15 Aug 2012 09:05:01 +0200 [thread overview]
Message-ID: <1345014301-5855-1-git-send-email-s.priebe@profihost.ag> (raw)
---
block/iscsi.c | 55 +++++++++++++++++++++++--------------------------------
1 files changed, 23 insertions(+), 32 deletions(-)
diff --git a/block/iscsi.c b/block/iscsi.c
index 12ca76d..1c8b049 100644
--- a/block/iscsi.c
+++ b/block/iscsi.c
@@ -76,6 +76,10 @@ static void
iscsi_abort_task_cb(struct iscsi_context *iscsi, int status, void *command_data,
void *private_data)
{
+ IscsiAIOCB *acb = (IscsiAIOCB *)private_data;
+
+ scsi_free_scsi_task(acb->task);
+ acb->task = NULL;
}
static void
@@ -84,15 +88,15 @@ iscsi_aio_cancel(BlockDriverAIOCB *blockacb)
IscsiAIOCB *acb = (IscsiAIOCB *)blockacb;
IscsiLun *iscsilun = acb->iscsilun;
- acb->common.cb(acb->common.opaque, -ECANCELED);
acb->canceled = 1;
- /* send a task mgmt call to the target to cancel the task on the target */
- iscsi_task_mgmt_abort_task_async(iscsilun->iscsi, acb->task,
- iscsi_abort_task_cb, NULL);
+ acb->common.cb(acb->common.opaque, -ECANCELED);
- /* then also cancel the task locally in libiscsi */
- iscsi_scsi_task_cancel(iscsilun->iscsi, acb->task);
+ /* send a task mgmt call to the target to cancel the task on the target
+ * this also cancels the task in libiscsi
+ */
+ iscsi_task_mgmt_abort_task_async(iscsilun->iscsi, acb->task,
+ iscsi_abort_task_cb, &acb);
}
static AIOPool iscsi_aio_pool = {
@@ -179,11 +183,18 @@ iscsi_readv_writev_bh_cb(void *p)
qemu_bh_delete(acb->bh);
- if (acb->canceled == 0) {
+ if (!acb->canceled) {
acb->common.cb(acb->common.opaque, acb->status);
}
qemu_aio_release(acb);
+
+ if (acb->canceled) {
+ return;
+ }
+
+ scsi_free_scsi_task(acb->task);
+ acb->task = NULL;
}
@@ -197,10 +208,8 @@ iscsi_aio_write16_cb(struct iscsi_context *iscsi, int status,
g_free(acb->buf);
- if (acb->canceled != 0) {
+ if (acb->canceled) {
qemu_aio_release(acb);
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
return;
}
@@ -212,8 +221,6 @@ iscsi_aio_write16_cb(struct iscsi_context *iscsi, int status,
}
iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb);
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
}
static int64_t sector_qemu2lun(int64_t sector, IscsiLun *iscsilun)
@@ -298,10 +305,8 @@ iscsi_aio_read16_cb(struct iscsi_context *iscsi, int status,
trace_iscsi_aio_read16_cb(iscsi, status, acb, acb->canceled);
- if (acb->canceled != 0) {
+ if (acb->canceled) {
qemu_aio_release(acb);
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
return;
}
@@ -313,8 +318,6 @@ iscsi_aio_read16_cb(struct iscsi_context *iscsi, int status,
}
iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb);
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
}
static BlockDriverAIOCB *
@@ -414,10 +417,8 @@ iscsi_synccache10_cb(struct iscsi_context *iscsi, int status,
{
IscsiAIOCB *acb = opaque;
- if (acb->canceled != 0) {
+ if (acb->canceled) {
qemu_aio_release(acb);
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
return;
}
@@ -429,8 +430,6 @@ iscsi_synccache10_cb(struct iscsi_context *iscsi, int status,
}
iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb);
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
}
static BlockDriverAIOCB *
@@ -468,10 +467,8 @@ iscsi_unmap_cb(struct iscsi_context *iscsi, int status,
{
IscsiAIOCB *acb = opaque;
- if (acb->canceled != 0) {
+ if (acb->canceled) {
qemu_aio_release(acb);
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
return;
}
@@ -483,8 +480,6 @@ iscsi_unmap_cb(struct iscsi_context *iscsi, int status,
}
iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb);
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
}
static BlockDriverAIOCB *
@@ -528,10 +523,8 @@ iscsi_aio_ioctl_cb(struct iscsi_context *iscsi, int status,
{
IscsiAIOCB *acb = opaque;
- if (acb->canceled != 0) {
+ if (acb->canceled) {
qemu_aio_release(acb);
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
return;
}
@@ -560,8 +553,6 @@ iscsi_aio_ioctl_cb(struct iscsi_context *iscsi, int status,
}
iscsi_schedule_bh(iscsi_readv_writev_bh_cb, acb);
- scsi_free_scsi_task(acb->task);
- acb->task = NULL;
}
static BlockDriverAIOCB *iscsi_aio_ioctl(BlockDriverState *bs,
--
1.7.2.5
next reply other threads:[~2012-08-15 7:05 UTC|newest]
Thread overview: 6+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-08-15 7:05 Stefan Priebe [this message]
-- strict thread matches above, loose matches on Subject: below --
2012-08-15 7:09 [Qemu-devel] PATCH V2: fix NULL dereferences / races between task completition and abort Stefan Priebe
2012-08-15 7:09 ` [Qemu-devel] [PATCH] " Stefan Priebe
2012-08-15 7:10 ` Stefan Priebe - Profihost AG
2012-08-15 8:13 ` ronnie sahlberg
2012-08-15 10:20 ` Kevin Wolf
2012-08-14 20:29 Stefan Priebe
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