diff options
| author | Roland Dreier <rolandd@cisco.com> | 2005-06-27 14:36:46 -0700 | 
|---|---|---|
| committer | Linus Torvalds <torvalds@ppc970.osdl.org> | 2005-06-27 15:11:47 -0700 | 
| commit | dae4c1d2362292ccd3318ff67d18aa5c22ee820c (patch) | |
| tree | 2bab3983a784bd6baef0fda8f8a62a555f38cb99 /drivers/infiniband/core | |
| parent | cae54bdf6f8b643e0e7a36ed531951f19e14fe56 (diff) | |
[PATCH] IB: Fix race in sa_query
Use a copy of the id we'll return to the consumer so that we don't
dereference query->sa_query after calling send_mad().  A completion may
occur very quickly and end up freeing the query before we get to do
anything after send_mad().
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'drivers/infiniband/core')
| -rw-r--r-- | drivers/infiniband/core/sa_query.c | 18 | 
1 files changed, 13 insertions, 5 deletions
| diff --git a/drivers/infiniband/core/sa_query.c b/drivers/infiniband/core/sa_query.c index 276e1a53010..5a08e81fa82 100644 --- a/drivers/infiniband/core/sa_query.c +++ b/drivers/infiniband/core/sa_query.c @@ -507,7 +507,13 @@ retry:  		spin_unlock_irqrestore(&idr_lock, flags);  	} -	return ret; +	/* +	 * It's not safe to dereference query any more, because the +	 * send may already have completed and freed the query in +	 * another context.  So use wr.wr_id, which has a copy of the +	 * query's id. +	 */ +	return ret ? ret : wr.wr_id;  }  static void ib_sa_path_rec_callback(struct ib_sa_query *sa_query, @@ -598,14 +604,15 @@ int ib_sa_path_rec_get(struct ib_device *device, u8 port_num,  		rec, query->sa_query.mad->data);  	*sa_query = &query->sa_query; +  	ret = send_mad(&query->sa_query, timeout_ms); -	if (ret) { +	if (ret < 0) {  		*sa_query = NULL;  		kfree(query->sa_query.mad);  		kfree(query);  	} -	return ret ? ret : query->sa_query.id; +	return ret;  }  EXPORT_SYMBOL(ib_sa_path_rec_get); @@ -674,14 +681,15 @@ int ib_sa_mcmember_rec_query(struct ib_device *device, u8 port_num,  		rec, query->sa_query.mad->data);  	*sa_query = &query->sa_query; +  	ret = send_mad(&query->sa_query, timeout_ms); -	if (ret) { +	if (ret < 0) {  		*sa_query = NULL;  		kfree(query->sa_query.mad);  		kfree(query);  	} -	return ret ? ret : query->sa_query.id; +	return ret;  }  EXPORT_SYMBOL(ib_sa_mcmember_rec_query); | 
