Commit Graph

8 Commits

Author SHA1 Message Date
Guillaume Nault 1bec9d0c00 ipv4: Convert ->flowi4_tos to dscp_t.
Convert the ->flowic_tos field of struct flowi_common from __u8 to
dscp_t, rename it ->flowic_dscp and propagate these changes to struct
flowi and struct flowi4.

We've had several bugs in the past where ECN bits could interfere with
IPv4 routing, because these bits were not properly cleared when setting
->flowi4_tos. These bugs should be fixed now and the dscp_t type has
been introduced to ensure that variables carrying DSCP values don't
accidentally have any ECN bits set. Several variables and structure
fields have been converted to dscp_t already, but the main IPv4 routing
structure, struct flowi4, is still using a __u8. To avoid any future
regression, this patch converts it to dscp_t.

There are many users to convert at once. Fortunately, around half of
->flowi4_tos users already have a dscp_t value at hand, which they
currently convert to __u8 using inet_dscp_to_dsfield(). For all of
these users, we just need to drop that conversion.

But, although we try to do the __u8 <-> dscp_t conversions at the
boundaries of the network or of user space, some places still store
TOS/DSCP variables as __u8 in core networking code. Those can hardly be
converted either because the data structure is part of UAPI or because
the same variable or field is also used for handling ECN in other parts
of the code. In all of these cases where we don't have a dscp_t
variable at hand, we need to use inet_dsfield_to_dscp() when
interacting with ->flowi4_dscp.

Changes since v1:
  * Fix space alignment in __bpf_redirect_neigh_v4() (Ido).

Signed-off-by: Guillaume Nault <gnault@redhat.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Link: https://patch.msgid.link/29acecb45e911d17446b9a3dbdb1ab7b821ea371.1756128932.git.gnault@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-26 17:34:31 -07:00
Edward Cree 60bda1ba06 sfc: unfix not-a-typo in comment
Commit fe09560f82 ("net: Fix typos") removed duplicated word 'fallback',
 but this was not a typo and change altered the semantic meaning of
 the comment.
Partially revert, using the phrase 'fallback of the fallback' to make
 the meaning more clear to future readers so that they won't try to
 change it again.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250731144138.2637949-1-edward.cree@amd.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-08-01 14:16:33 -07:00
Bjorn Helgaas fe09560f82 net: Fix typos
Fix typos in comments and error messages.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: David Arinzon <darinzon@amazon.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250723201528.2908218-1-helgaas@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-07-25 10:29:07 -07:00
Edward Cree fc21f08375 sfc: handle error pointers returned by rhashtable_lookup_get_insert_fast()
Several places in TC offload code assumed that the return from
 rhashtable_lookup_get_insert_fast() was always either NULL or a valid
 pointer to an existing entry, but in fact that function can return an
 error pointer.  In that case, perform the usual cleanup of the newly
 created entry, then pass up the error, rather than attempting to take a
 reference on the old entry.

Fixes: d902e1a737 ("sfc: bare bones TC offload on EF100")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Link: https://lore.kernel.org/r/20230919183949.59392-1-edward.cree@amd.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2023-09-21 10:37:16 +02:00
Arnd Bergmann f61d2d5cf1 sfc: fix uninitialized variable use
The new efx_bind_neigh() function contains a broken code path when IPV6 is
disabled:

drivers/net/ethernet/sfc/tc_encap_actions.c:144:7: error: variable 'n' is used uninitialized whenever 'if' condition is true [-Werror,-Wsometimes-uninitialized]
                if (encap->type & EFX_ENCAP_FLAG_IPV6) {
                    ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/sfc/tc_encap_actions.c:184:8: note: uninitialized use occurs here
                if (!n) {
                     ^
drivers/net/ethernet/sfc/tc_encap_actions.c:144:3: note: remove the 'if' if its condition is always false
                if (encap->type & EFX_ENCAP_FLAG_IPV6) {
                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/net/ethernet/sfc/tc_encap_actions.c:141:22: note: initialize the variable 'n' to silence this warning
                struct neighbour *n;
                                   ^
                                    = NULL

Change it to use the existing error handling path here.

Fixes: 7e5e7d8000 ("sfc: neighbour lookup for TC encap action offload")
Suggested-by: Edward Cree <ecree.xilinx@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Reviewed-by: Edward Cree <ecree.xilinx@gmail.com>
Link: https://lore.kernel.org/r/20230619091215.2731541-2-arnd@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-20 20:37:16 -07:00
Edward Cree a1e82162af sfc: generate encap headers for TC offload
Support constructing VxLAN and GENEVE headers, on either IPv4 or IPv6,
 using the neighbouring information obtained in encap->neigh to
 populate the Ethernet header.
Note that the ef100 hardware does not insert UDP checksums when
 performing encap, so for IPv6 the remote endpoint will need to be
 configured with udp6zerocsumrx or equivalent.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-10 00:11:50 -07:00
Edward Cree 7e5e7d8000 sfc: neighbour lookup for TC encap action offload
For each neighbour we're interested in, create a struct efx_neigh_binder
 object which has a list of all the encap_actions using it.  When we
 receive a neighbouring update (through the netevent notifier), find the
 corresponding efx_neigh_binder and update all its users.
Since the actual generation of encap headers is still only a stub, the
 resulting rules still get left on fallback actions.

Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-10 00:11:49 -07:00
Edward Cree b4da4235dc sfc: some plumbing towards TC encap action offload
Create software objects to manage the metadata for encap actions that
 can be attached to TC rules.  However, since we don't yet have the
 neighbouring information (needed to generate the Ethernet header),
 all rules with encap actions are marked as "unready" and thus insert
 the fallback action into hardware rather than actually offloading the
 encapsulation action.

Reviewed-by: Pieter Jansen van Vuuren <pieter.jansen-van-vuuren@amd.com>
Signed-off-by: Edward Cree <ecree.xilinx@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2023-06-10 00:11:49 -07:00