[PATCH net] sfc: handle rhashtable walk errors in mport lookup

[PATCH net] sfc: handle rhashtable walk errors in mport lookup

[Sang-Hoon Choi]

rhashtable_walk_next() can return ERR_PTR(-EAGAIN) when the table is
resized. efx_mae_lookup_mport() currently dereferences that value as an
mport descriptor.

Skip error values and continue the walk, as the other rhashtable walkers
in this driver already do.

Fixes: 5227adff37af ("sfc: add mport lookup based on driver's mport data")
Reported-by: Changyul Lee <lcy8047@gmail.com>
Assisted-by: LLM
Signed-off-by: Sang-Hoon Choi <csh0052@gmail.com>
---
Compile-tested the affected object with x86_64 allmodconfig
and W=1 (GCC 13.3.0). Base: mainline 3b7cab693ba2bab63774bf5b988e8a61b2ef0f32.
No hardware testing or runtime failure reproduction was performed.

 drivers/net/ethernet/sfc/mae.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/sfc/mae.c b/drivers/net/ethernet/sfc/mae.c
index 7a8606efd492..b6de61062a86 100644
--- a/drivers/net/ethernet/sfc/mae.c
+++ b/drivers/net/ethernet/sfc/mae.c
@@ -1030,6 +1030,8 @@ int efx_mae_lookup_mport(struct efx_nic *efx, u32 vf_idx, u32 *id)
 	rhashtable_walk_enter(&mae->mports_ht, &walk);
 	rhashtable_walk_start(&walk);
 	while ((m = rhashtable_walk_next(&walk)) != NULL) {
+		if (IS_ERR(m))
+			continue;
 		if (m->mport_type == MAE_MPORT_DESC_MPORT_TYPE_VNIC &&
 		    m->interface_idx == nic_data->local_mae_intf &&
 		    m->pf_idx == 0 &&

Re: [PATCH net] sfc: handle rhashtable walk errors in mport lookup

[Simon Horman]

On Fri, Oct 02, 2026 at 07:47:40PM +0000, Sang-Hoon Choi wrote:
> rhashtable_walk_next() can return ERR_PTR(-EAGAIN) when the table is
> resized. efx_mae_lookup_mport() currently dereferences that value as an
> mport descriptor.
> 
> Skip error values and continue the walk, as the other rhashtable walkers
> in this driver already do.
> 
> Fixes: 5227adff37af ("sfc: add mport lookup based on driver's mport data")
> Reported-by: Changyul Lee <lcy8047@gmail.com>
> Assisted-by: LLM
> Signed-off-by: Sang-Hoon Choi <csh0052@gmail.com>
> ---
> Compile-tested the affected object with x86_64 allmodconfig
> and W=1 (GCC 13.3.0). Base: mainline 3b7cab693ba2bab63774bf5b988e8a61b2ef0f32.
> No hardware testing or runtime failure reproduction was performed.

Reviewed-by: Simon Horman <horms@kernel.org>

Re: [PATCH net] sfc: handle rhashtable walk errors in mport lookup

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net-next.git (main)
by Jakub Kicinski <kuba@kernel.org>:

On Fri, 02 Oct 2026 19:47:40 +0000 you wrote:
> rhashtable_walk_next() can return ERR_PTR(-EAGAIN) when the table is
> resized. efx_mae_lookup_mport() currently dereferences that value as an
> mport descriptor.
> 
> Skip error values and continue the walk, as the other rhashtable walkers
> in this driver already do.
> 
> [...]

Here is the summary with links:
  - [net] sfc: handle rhashtable walk errors in mport lookup
    https://git.kernel.org/netdev/net-next/c/2a1359aa651f

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html