From: Vlad Dogaru vdogaru@nvidia.com
[ Upstream commit 6991a975e416154576b0f5f06256aec13e23b0a7 ]
Replicate some sanity checks that firmware does, since hardware steering does not go through firmware.
When creating a definer, disallow matching on IP addresses without also matching on IP version. The latter can be satisfied by matching either on the version field in the IP header, or on the ethertype field.
Also refuse to match IPv4 IHL alongside IPv6.
Signed-off-by: Vlad Dogaru vdogaru@nvidia.com Reviewed-by: Yevgeny Kliteynik kliteyn@nvidia.com Signed-off-by: Mark Bloch mbloch@nvidia.com Link: https://patch.msgid.link/20250422092540.182091-3-mbloch@nvidia.com Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org ---
**YES** This commit should be backported to stable kernel trees based on the following analysis: ## Nature of the Change This is a **hardening/validation fix** that adds critical input validation to prevent invalid hardware configurations. The code changes add two essential checks: 1. **IP Address Version Validation**: Ensures that when matching on IP addresses, either IP version or ethertype is also specified 2. **Protocol Consistency Check**: Prevents matching IPv6 addresses alongside IPv4-specific fields like IHL (Internet Header Length) ## Code Analysis The changes are purely additive validation logic in `hws_definer_conv_outer()` and `hws_definer_conv_inner()`: ```c // Prevents matching IP addresses without version specification if (ip_addr_set && !ip_ver_set) { mlx5hws_err(cd->ctx, "Unsupported match on IP address without version or ethertype\n"); return -EINVAL; } // Prevents IPv6/IPv4 field conflicts if (is_ipv6 && HWS_IS_FLD_SET(match_param, outer_headers.ipv4_ihl)) { mlx5hws_err(cd->ctx, "Unsupported match on IPv6 address and IPv4 IHL\n"); return -EINVAL; } ``` ## Critical Context As stated in the commit message, this "replicates sanity checks that firmware does, since hardware steering does not go through firmware." This is essential because: - Hardware Steering (HWS) bypasses normal firmware validation paths - Without these checks, invalid configurations could reach the hardware - Invalid configurations could cause hardware errors or undefined behavior ## Similarity to Established Patterns This follows the same pattern as **Similar Commit #4** (marked YES for backporting), which added similar validation for IP matching requirements in software steering with the message "Don't allow match on IP w/o matching on full ethertype/ip_version." ## Backporting Justification 1. **Low Risk**: Only adds validation, doesn't change functional behavior 2. **High Value**: Prevents potential hardware errors and system instability 3. **Defensive Programming**: Early error detection with clear diagnostic messages 4. **No Dependencies**: Uses existing error reporting infrastructure 5. **Protocol Compliance**: Ensures proper IP protocol field usage This type of input validation and hardware protection logic is exactly what stable kernel trees need to maintain system reliability and prevent configuration errors that could cause more serious issues.
.../mlx5/core/steering/hws/mlx5hws_definer.c | 44 ++++++++++++++++++- 1 file changed, 42 insertions(+), 2 deletions(-)
diff --git a/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_definer.c b/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_definer.c index 5cabde7098b68..678e2539cf312 100644 --- a/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_definer.c +++ b/drivers/net/ethernet/mellanox/mlx5/core/steering/hws/mlx5hws_definer.c @@ -508,9 +508,9 @@ static int hws_definer_conv_outer(struct mlx5hws_definer_conv_data *cd, u32 *match_param) { + bool is_ipv6, smac_set, dmac_set, ip_addr_set, ip_ver_set; struct mlx5hws_definer_fc *fc = cd->fc; struct mlx5hws_definer_fc *curr_fc; - bool is_ipv6, smac_set, dmac_set; u32 *s_ipv6, *d_ipv6;
if (HWS_IS_FLD_SET_SZ(match_param, outer_headers.l4_type, 0x2) || @@ -520,6 +520,20 @@ hws_definer_conv_outer(struct mlx5hws_definer_conv_data *cd, return -EINVAL; }
+ ip_addr_set = HWS_IS_FLD_SET_SZ(match_param, + outer_headers.src_ipv4_src_ipv6, + 0x80) || + HWS_IS_FLD_SET_SZ(match_param, + outer_headers.dst_ipv4_dst_ipv6, 0x80); + ip_ver_set = HWS_IS_FLD_SET(match_param, outer_headers.ip_version) || + HWS_IS_FLD_SET(match_param, outer_headers.ethertype); + + if (ip_addr_set && !ip_ver_set) { + mlx5hws_err(cd->ctx, + "Unsupported match on IP address without version or ethertype\n"); + return -EINVAL; + } + /* L2 Check ethertype */ HWS_SET_HDR(fc, match_param, ETH_TYPE_O, outer_headers.ethertype, @@ -572,6 +586,12 @@ hws_definer_conv_outer(struct mlx5hws_definer_conv_data *cd, is_ipv6 = s_ipv6[0] || s_ipv6[1] || s_ipv6[2] || d_ipv6[0] || d_ipv6[1] || d_ipv6[2];
+ /* IHL is an IPv4-specific field. */ + if (is_ipv6 && HWS_IS_FLD_SET(match_param, outer_headers.ipv4_ihl)) { + mlx5hws_err(cd->ctx, "Unsupported match on IPv6 address and IPv4 IHL\n"); + return -EINVAL; + } + if (is_ipv6) { /* Handle IPv6 source address */ HWS_SET_HDR(fc, match_param, IPV6_SRC_127_96_O, @@ -661,9 +681,9 @@ static int hws_definer_conv_inner(struct mlx5hws_definer_conv_data *cd, u32 *match_param) { + bool is_ipv6, smac_set, dmac_set, ip_addr_set, ip_ver_set; struct mlx5hws_definer_fc *fc = cd->fc; struct mlx5hws_definer_fc *curr_fc; - bool is_ipv6, smac_set, dmac_set; u32 *s_ipv6, *d_ipv6;
if (HWS_IS_FLD_SET_SZ(match_param, inner_headers.l4_type, 0x2) || @@ -673,6 +693,20 @@ hws_definer_conv_inner(struct mlx5hws_definer_conv_data *cd, return -EINVAL; }
+ ip_addr_set = HWS_IS_FLD_SET_SZ(match_param, + inner_headers.src_ipv4_src_ipv6, + 0x80) || + HWS_IS_FLD_SET_SZ(match_param, + inner_headers.dst_ipv4_dst_ipv6, 0x80); + ip_ver_set = HWS_IS_FLD_SET(match_param, inner_headers.ip_version) || + HWS_IS_FLD_SET(match_param, inner_headers.ethertype); + + if (ip_addr_set && !ip_ver_set) { + mlx5hws_err(cd->ctx, + "Unsupported match on IP address without version or ethertype\n"); + return -EINVAL; + } + /* L2 Check ethertype */ HWS_SET_HDR(fc, match_param, ETH_TYPE_I, inner_headers.ethertype, @@ -727,6 +761,12 @@ hws_definer_conv_inner(struct mlx5hws_definer_conv_data *cd, is_ipv6 = s_ipv6[0] || s_ipv6[1] || s_ipv6[2] || d_ipv6[0] || d_ipv6[1] || d_ipv6[2];
+ /* IHL is an IPv4-specific field. */ + if (is_ipv6 && HWS_IS_FLD_SET(match_param, inner_headers.ipv4_ihl)) { + mlx5hws_err(cd->ctx, "Unsupported match on IPv6 address and IPv4 IHL\n"); + return -EINVAL; + } + if (is_ipv6) { /* Handle IPv6 source address */ HWS_SET_HDR(fc, match_param, IPV6_SRC_127_96_I,