cxgb4: Annotate struct cxgb4_tc_u32_table with __counted_by

Prepare for the coming implementation by GCC and Clang of the __counted_by
attribute. Flexible array members annotated with __counted_by can have
their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
(for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
functions).

As found with Coccinelle[1], add __counted_by for struct cxgb4_tc_u32_table.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

Cc: Raju Rangoju <rajur@chelsio.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230929181149.3006432-3-keescook@chromium.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

cxgb4: parse TC-U32 key values and masks natively

TC-U32 passes all keys values and masks in __be32 format. The parser
already expects this and hence pass the value and masks in __be32
natively to the parser.

Fixes following sparse warnings in several places:
cxgb4_tc_u32.c:57:21: warning: incorrect type in assignment (different base
types)
cxgb4_tc_u32.c:57:21: expected unsigned int [usertype] val
cxgb4_tc_u32.c:57:21: got restricted __be32 [usertype] val
cxgb4_tc_u32_parse.h:48:24: warning: cast to restricted __be32

Fixes: 2e8aad7bf203 ("cxgb4: add parser to translate u32 filters to internal spec")
Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

chelsio: Replace zero-length array with flexible-array member

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
int stuff;
struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

cxgb4: add support for offloading u32 filters

Add support for offloading u32 filter onto hardware. Links are stored
in a jump table to perform necessary jumps to match TCP/UDP header.
When inserting rules in the linked bucket, the TCP/UDP match fields
in the corresponding entry of the jump table are appended to the filter
rule before insertion. If a link is deleted, then all corresponding
filters associated with the link are also deleted. Also enable
hardware tc offload as a supported feature.

Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

cxgb4: add parser to translate u32 filters to internal spec

Parse information sent by u32 into internal filter specification.
Add support for parsing several fields in IPv4, IPv6, TCP, and UDP.

Signed-off-by: Rahul Lakkireddy <rahul.lakkireddy@chelsio.com>
Signed-off-by: Hariprasad Shenai <hariprasad@chelsio.com>
Signed-off-by: David S. Miller <davem@davemloft.net>