net: atlantic: fix double free in ring reinit logic
Driver has a logic leak in ring data allocation/free,
where double free may happen in aq_ring_free if system is under
stress and driver init/deinit is happening.
The probability is higher to get this during suspend/resume cycle.
Verification was done simulating same conditions with
stress -m 2000 --vm-bytes 20M --vm-hang 10 --backoff 1000
while true; do sudo ifconfig enp1s0 down; sudo ifconfig enp1s0 up; done
Fixed by explicitly clearing pointers to NULL on deallocation
Fixes: 018423e90bee ("net: ethernet: aquantia: Add ring support code")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Closes: https://lore.kernel.org/netdev/CAHk-=wiZZi7FcvqVSUirHBjx0bBUZ4dFrMDVLc3+3HCrtq0rBA@mail.gmail.com/
Signed-off-by: Igor Russkikh <irusskikh@marvell.com>
Link: https://lore.kernel.org/r/20231213094044.22988-1-irusskikh@marvell.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
diff --git a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
index 694daea..e1885c1 100644
--- a/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
+++ b/drivers/net/ethernet/aquantia/atlantic/aq_ring.c
@@ -938,11 +938,14 @@ void aq_ring_free(struct aq_ring_s *self)
return;
kfree(self->buff_ring);
+ self->buff_ring = NULL;
- if (self->dx_ring)
+ if (self->dx_ring) {
dma_free_coherent(aq_nic_get_dev(self->aq_nic),
self->size * self->dx_size, self->dx_ring,
self->dx_ring_pa);
+ self->dx_ring = NULL;
+ }
}
unsigned int aq_ring_fill_stats_data(struct aq_ring_s *self, u64 *data)
