Commit 84328342 authored by Michael S. Tsirkin's avatar Michael S. Tsirkin Committed by David S. Miller
Browse files

ptr_ring: disallow lockless __ptr_ring_full

Similar to bcecb4bb

 ("net: ptr_ring: otherwise safe empty checks can
overrun array bounds") a lockless use of __ptr_ring_full might
cause an out of bounds access.

We can fix this, but it's easier to just disallow lockless
__ptr_ring_full for now.
Signed-off-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 88fae873
......@@ -45,9 +45,10 @@ struct ptr_ring {
};
/* Note: callers invoking this in a loop must use a compiler barrier,
* for example cpu_relax(). If ring is ever resized, callers must hold
* producer_lock - see e.g. ptr_ring_full. Otherwise, if callers don't hold
* producer_lock, the next call to __ptr_ring_produce may fail.
* for example cpu_relax().
*
* NB: this is unlike __ptr_ring_empty in that callers must hold producer_lock:
* see e.g. ptr_ring_full.
*/
static inline bool __ptr_ring_full(struct ptr_ring *r)
{
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment