| Message ID | 20230821180153.18652-1-edward.cree@amd.com (mailing list archive) |
|---|---|
| State | Accepted |
| Commit | 6dc5774deefe38d9ab385a5dafbe6614ae63d166 |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | [net] sfc: allocate a big enough SKB for loopback selftest packet | expand |
On Mon, Aug 21, 2023 at 07:01:53PM +0100, edward.cree@amd.com wrote: > From: Edward Cree <ecree.xilinx@gmail.com> > > Cited commits passed a size to alloc_skb that was only big enough for > the actual packet contents, but the following skb_put + memcpy writes > the whole struct efx_loopback_payload including leading and trailing > padding bytes (which are then stripped off with skb_pull/skb_trim). > This could cause an skb_over_panic, although in practice we get saved > by kmalloc_size_roundup. > Pass the entire size we use, instead of the size of the final packet. > > Reported-by: Andy Moreton <andy.moreton@amd.com> > Fixes: cf60ed469629 ("sfc: use padding to fix alignment in loopback test") > Fixes: 30c24dd87f3f ("sfc: siena: use padding to fix alignment in loopback test") > Fixes: 1186c6b31ee1 ("sfc: falcon: use padding to fix alignment in loopback test") > Signed-off-by: Edward Cree <ecree.xilinx@gmail.com> Reviewed-by: Simon Horman <horms@kernel.org>
Hello: This patch was applied to netdev/net.git (main) by Jakub Kicinski <kuba@kernel.org>: On Mon, 21 Aug 2023 19:01:53 +0100 you wrote: > From: Edward Cree <ecree.xilinx@gmail.com> > > Cited commits passed a size to alloc_skb that was only big enough for > the actual packet contents, but the following skb_put + memcpy writes > the whole struct efx_loopback_payload including leading and trailing > padding bytes (which are then stripped off with skb_pull/skb_trim). > This could cause an skb_over_panic, although in practice we get saved > by kmalloc_size_roundup. > Pass the entire size we use, instead of the size of the final packet. > > [...] Here is the summary with links: - [net] sfc: allocate a big enough SKB for loopback selftest packet https://git.kernel.org/netdev/net/c/6dc5774deefe You are awesome, thank you!
diff --git a/drivers/net/ethernet/sfc/falcon/selftest.c b/drivers/net/ethernet/sfc/falcon/selftest.c index cf1d67b6d86d..c3dc88e6c26c 100644 --- a/drivers/net/ethernet/sfc/falcon/selftest.c +++ b/drivers/net/ethernet/sfc/falcon/selftest.c @@ -428,7 +428,7 @@ static int ef4_begin_loopback(struct ef4_tx_queue *tx_queue) for (i = 0; i < state->packet_count; i++) { /* Allocate an skb, holding an extra reference for * transmit completion counting */ - skb = alloc_skb(EF4_LOOPBACK_PAYLOAD_LEN, GFP_KERNEL); + skb = alloc_skb(sizeof(state->payload), GFP_KERNEL); if (!skb) return -ENOMEM; state->skbs[i] = skb; diff --git a/drivers/net/ethernet/sfc/selftest.c b/drivers/net/ethernet/sfc/selftest.c index 19a0b8584afb..563c1e317ce9 100644 --- a/drivers/net/ethernet/sfc/selftest.c +++ b/drivers/net/ethernet/sfc/selftest.c @@ -426,7 +426,7 @@ static int efx_begin_loopback(struct efx_tx_queue *tx_queue) for (i = 0; i < state->packet_count; i++) { /* Allocate an skb, holding an extra reference for * transmit completion counting */ - skb = alloc_skb(EFX_LOOPBACK_PAYLOAD_LEN, GFP_KERNEL); + skb = alloc_skb(sizeof(state->payload), GFP_KERNEL); if (!skb) return -ENOMEM; state->skbs[i] = skb; diff --git a/drivers/net/ethernet/sfc/siena/selftest.c b/drivers/net/ethernet/sfc/siena/selftest.c index b55fd3346972..526da43d4b61 100644 --- a/drivers/net/ethernet/sfc/siena/selftest.c +++ b/drivers/net/ethernet/sfc/siena/selftest.c @@ -426,7 +426,7 @@ static int efx_begin_loopback(struct efx_tx_queue *tx_queue) for (i = 0; i < state->packet_count; i++) { /* Allocate an skb, holding an extra reference for * transmit completion counting */ - skb = alloc_skb(EFX_LOOPBACK_PAYLOAD_LEN, GFP_KERNEL); + skb = alloc_skb(sizeof(state->payload), GFP_KERNEL); if (!skb) return -ENOMEM; state->skbs[i] = skb;