6.9-stable review patch. If anyone has any objections, please let me know.
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From: Saeed Mahameed saeedm@nvidia.com
[ Upstream commit 503757c809281a24d50ac2538401d3b1302b301c ]
When user submits a rxfh set command without touching XFRM_SYM_XOR, rxfh.input_xfrm is set to RXH_XFRM_NO_CHANGE, which is equal to 0xff.
Testing if (rxfh.input_xfrm & RXH_XFRM_SYM_XOR && !ops->cap_rss_sym_xor_supported) return -EOPNOTSUPP;
Will always be true on devices that don't set cap_rss_sym_xor_supported, since rxfh.input_xfrm & RXH_XFRM_SYM_XOR is always true, if input_xfrm was not set, i.e RXH_XFRM_NO_CHANGE=0xff, which will result in failure of any command that doesn't require any change of XFRM, e.g RSS context or hash function changes.
To avoid this breakage, test if rxfh.input_xfrm != RXH_XFRM_NO_CHANGE before testing other conditions. Note that the problem will only trigger with XFRM-aware userspace, old ethtool CLI would continue to work.
Fixes: 0dd415d15505 ("net: ethtool: add a NO_CHANGE uAPI for new RXFH's input_xfrm") Signed-off-by: Saeed Mahameed saeedm@nvidia.com Reviewed-by: Ahmed Zaki ahmed.zaki@intel.com Link: https://patch.msgid.link/20240710225538.43368-1-saeed@kernel.org Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/ethtool/ioctl.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/net/ethtool/ioctl.c b/net/ethtool/ioctl.c index e645d751a5e89..223dcd25d88a2 100644 --- a/net/ethtool/ioctl.c +++ b/net/ethtool/ioctl.c @@ -1306,7 +1306,8 @@ static noinline_for_stack int ethtool_set_rxfh(struct net_device *dev, if (rxfh.input_xfrm && rxfh.input_xfrm != RXH_XFRM_SYM_XOR && rxfh.input_xfrm != RXH_XFRM_NO_CHANGE) return -EINVAL; - if ((rxfh.input_xfrm & RXH_XFRM_SYM_XOR) && + if (rxfh.input_xfrm != RXH_XFRM_NO_CHANGE && + (rxfh.input_xfrm & RXH_XFRM_SYM_XOR) && !ops->cap_rss_sym_xor_supported) return -EOPNOTSUPP;