lk/linux-kernel-test
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

IB/mad: Fix null pointer dereference in local_completions()

Browse Source 
handle_outgoing_dr_smp() can queue a struct ib_mad_local_private
*local on the mad_agent_priv->local_work work queue with
local->mad_priv == NULL if device->process_mad() returns
IB_MAD_RESULT_SUCCESS | IB_MAD_RESULT_REPLY and
(!ib_response_mad(&mad_priv->mad.mad) ||
!mad_agent_priv->agent.recv_handler).

In this case, local_completions() will be called with local->mad_priv
== NULL. The code does check for this case and skips calling
recv_mad_agent->agent.recv_handler() but recv == 0 so
kmem_cache_free() is called with a NULL pointer.

Also, since recv isn't reinitialized each time through the loop, it
can cause a memory leak if recv should have been zero.

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
This commit is contained in:
Ralph Campbell
2009-02-27 10:34:30 -08:00
committed by Roland Dreier
parent 7020cb0fe2
commit 1d9bc6d648
1 changed files with 4 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
drivers/infiniband/core/mad.c
View File

@@ -2356,7 +2356,7 @@ static void local_completions(struct work_struct *work)
struct ib_mad_local_private *local; struct ib_mad_local_private *local;
struct ib_mad_agent_private *recv_mad_agent; struct ib_mad_agent_private *recv_mad_agent;
unsigned long flags; unsigned long flags;
int recv = 0; int free_mad;
struct ib_wc wc; struct ib_wc wc;
struct ib_mad_send_wc mad_send_wc; struct ib_mad_send_wc mad_send_wc;
@@ -2370,14 +2370,15 @@ static void local_completions(struct work_struct *work)
completion_list); completion_list);
list_del(&local->completion_list); list_del(&local->completion_list);
spin_unlock_irqrestore(&mad_agent_priv->lock, flags); spin_unlock_irqrestore(&mad_agent_priv->lock, flags);
free_mad = 0;
if (local->mad_priv) { if (local->mad_priv) {
recv_mad_agent = local->recv_mad_agent; recv_mad_agent = local->recv_mad_agent;
if (!recv_mad_agent) { if (!recv_mad_agent) {
printk(KERN_ERR PFX "No receive MAD agent for local completion\n"); printk(KERN_ERR PFX "No receive MAD agent for local completion\n");
free_mad = 1;
goto local_send_completion; goto local_send_completion;
} }
recv = 1;
/* /*
* Defined behavior is to complete response * Defined behavior is to complete response
* before request * before request
@@ -2422,7 +2423,7 @@ local_send_completion:
spin_lock_irqsave(&mad_agent_priv->lock, flags); spin_lock_irqsave(&mad_agent_priv->lock, flags);
atomic_dec(&mad_agent_priv->refcount); atomic_dec(&mad_agent_priv->refcount);
if (!recv) if (free_mad)
kmem_cache_free(ib_mad_cache, local->mad_priv); kmem_cache_free(ib_mad_cache, local->mad_priv);
kfree(local); kfree(local);
} }