linux.git/include/net/genetlink.h, branch v6.1 Linux kernel source tree genetlink: piggy back on resv_op to default to a reject policy 2022-10-25T02:08:46+00:00 Jakub Kicinski kuba@kernel.org 2022-10-21T19:35:32+00:00 4fa86555d1cd338afc6e6308cc1ff890a014ec8c To keep backward compatibility we used to leave attribute parsing to the family if no policy is specified. This becomes tedious as we move to more strict validation. Families must define reject all policies if they don't want any attributes accepted. Piggy back on the resv_start_op field as the switchover point. AFAICT only ethtool has added new commands since the resv_start_op was defined, and it has per-op policies so this should be a no-op. Nonetheless the patch should still go into v6.1 for consistency. Link: https://lore.kernel.org/all/20221019125745.3f2e7659@kernel.org/ Link: https://lore.kernel.org/r/20221021193532.1511293-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
To keep backward compatibility we used to leave attribute parsing
to the family if no policy is specified. This becomes tedious as
we move to more strict validation. Families must define reject all
policies if they don't want any attributes accepted.

Piggy back on the resv_start_op field as the switchover point.
AFAICT only ethtool has added new commands since the resv_start_op
was defined, and it has per-op policies so this should be a no-op.

Nonetheless the patch should still go into v6.1 for consistency.

Link: https://lore.kernel.org/all/20221019125745.3f2e7659@kernel.org/
Link: https://lore.kernel.org/r/20221021193532.1511293-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
genetlink: fix kdoc warnings 2022-10-19T20:08:30+00:00 Jakub Kicinski kuba@kernel.org 2022-10-18T23:13:10+00:00 a1a824f448ba96c610b85288d844adc9f781828e Address a bunch of kdoc warnings: include/net/genetlink.h:81: warning: Function parameter or member 'module' not described in 'genl_family' include/net/genetlink.h:243: warning: expecting prototype for struct genl_info. Prototype was for struct genl_dumpit_info instead include/net/genetlink.h:419: warning: Function parameter or member 'net' not described in 'genlmsg_unicast' include/net/genetlink.h:438: warning: expecting prototype for gennlmsg_data(). Prototype was for genlmsg_data() instead include/net/genetlink.h:244: warning: Function parameter or member 'op' not described in 'genl_dumpit_info' Link: https://lore.kernel.org/r/20221018231310.1040482-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Address a bunch of kdoc warnings:

include/net/genetlink.h:81: warning: Function parameter or member 'module' not described in 'genl_family'
include/net/genetlink.h:243: warning: expecting prototype for struct genl_info. Prototype was for struct genl_dumpit_info instead
include/net/genetlink.h:419: warning: Function parameter or member 'net' not described in 'genlmsg_unicast'
include/net/genetlink.h:438: warning: expecting prototype for gennlmsg_data(). Prototype was for genlmsg_data() instead
include/net/genetlink.h:244: warning: Function parameter or member 'op' not described in 'genl_dumpit_info'

Link: https://lore.kernel.org/r/20221018231310.1040482-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
netlink: add helpers for extack attr presence checking 2022-08-30T10:20:43+00:00 Jakub Kicinski kuba@kernel.org 2022-08-26T03:09:32+00:00 45dca15759643806660e9285e6af8a1ba3c76c82 Being able to check attribute presence and set extack if not on one line is handy, add helpers. Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: Jakub Kicinski <kuba@kernel.org> Signed-off-by: Paolo Abeni <pabeni@redhat.com> 
Being able to check attribute presence and set extack
if not on one line is handy, add helpers.

Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
genetlink: start to validate reserved header bytes 2022-08-29T11:47:15+00:00 Jakub Kicinski kuba@kernel.org 2022-08-25T00:18:30+00:00 9c5d03d362519f36cd551aec596388f895c93d2d We had historically not checked that genlmsghdr.reserved is 0 on input which prevents us from using those precious bytes in the future. One use case would be to extend the cmd field, which is currently just 8 bits wide and 256 is not a lot of commands for some core families. To make sure that new families do the right thing by default put the onus of opting out of validation on existing families. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Acked-by: Paul Moore <paul@paul-moore.com> (NetLabel) Signed-off-by: David S. Miller <davem@davemloft.net> 
We had historically not checked that genlmsghdr.reserved
is 0 on input which prevents us from using those precious
bytes in the future.

One use case would be to extend the cmd field, which is
currently just 8 bits wide and 256 is not a lot of commands
for some core families.

To make sure that new families do the right thing by default
put the onus of opting out of validation on existing families.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Paul Moore <paul@paul-moore.com> (NetLabel)
Signed-off-by: David S. Miller <davem@davemloft.net>
net: add missing kdoc for struct genl_multicast_group::flags 2022-08-11T16:26:04+00:00 Jakub Kicinski kuba@kernel.org 2022-08-09T23:20:12+00:00 5c221f0af68cfa9edcffd26ba6dbbc4b7ddb1700 Multicast group flags were added in commit 4d54cc32112d ("mptcp: avoid lock_fast usage in accept path"), but it missed adding the kdoc. Mention which flags go into that field, and do the same for op structs. Link: https://lore.kernel.org/r/20220809232012.403730-1-kuba@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org> 
Multicast group flags were added in commit 4d54cc32112d ("mptcp: avoid
lock_fast usage in accept path"), but it missed adding the kdoc.

Mention which flags go into that field, and do the same for
op structs.

Link: https://lore.kernel.org/r/20220809232012.403730-1-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
mptcp: avoid lock_fast usage in accept path 2021-02-13T00:31:46+00:00 Florian Westphal fw@strlen.de 2021-02-12T23:59:59+00:00 4d54cc32112d8d8b0667559c9309f1a6f764f70b Once event support is added this may need to allocate memory while msk lock is held with softirqs disabled. Not using lock_fast also allows to do the allocation with GFP_KERNEL. Signed-off-by: Florian Westphal <fw@strlen.de> Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com> Signed-off-by: David S. Miller <davem@davemloft.net> 
Once event support is added this may need to allocate memory while msk
lock is held with softirqs disabled.

Not using lock_fast also allows to do the allocation with GFP_KERNEL.

Signed-off-by: Florian Westphal <fw@strlen.de>
Signed-off-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net 2020-10-06T01:40:01+00:00 David S. Miller davem@davemloft.net 2020-10-06T00:33:26+00:00 8b0308fe319b8002753ea66f8f940fb393792ddd Rejecting non-native endian BTF overlapped with the addition of support for it. The rest were more simple overlapping changes, except the renesas ravb binding update, which had to follow a file move as well as a YAML conversion. Signed-off-by: David S. Miller <davem@davemloft.net> 
Rejecting non-native endian BTF overlapped with the addition
of support for it.

The rest were more simple overlapping changes, except the
renesas ravb binding update, which had to follow a file
move as well as a YAML conversion.

Signed-off-by: David S. Miller <davem@davemloft.net>
genetlink: bring back per op policy 2020-10-03T02:11:12+00:00 Jakub Kicinski kuba@kernel.org 2020-10-02T21:49:57+00:00 48526a0f4ca2b484cab4318dc0b2c2be1d8685b7 Add policy to the struct genl_ops structure, this time with maxattr, so it can be used properly. Propagate .policy and .maxattr from the family in genl_get_cmd() if needed, this way the rest of the code does not have to worry if the policy is per op or global. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net> 
Add policy to the struct genl_ops structure, this time
with maxattr, so it can be used properly.

Propagate .policy and .maxattr from the family
in genl_get_cmd() if needed, this way the rest of the
code does not have to worry if the policy is per op
or global.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
genetlink: add small version of ops 2020-10-03T02:11:11+00:00 Jakub Kicinski kuba@kernel.org 2020-10-02T21:49:53+00:00 0b588afdd16f9e0b63128dc4bcd002e7f2725fe0 We want to add maxattr and policy back to genl_ops, to enable dumping per command policy to user space. This, however, would cause bloat for all the families with global policies. Introduce smaller version of ops (half the size of genl_ops). Translate these smaller ops into a full blown struct before use in the core. v1: - use struct assignment - put a full copy of the op in struct genl_dumpit_info - s/light/small/ Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net> 
We want to add maxattr and policy back to genl_ops, to enable
dumping per command policy to user space. This, however, would
cause bloat for all the families with global policies. Introduce
smaller version of ops (half the size of genl_ops). Translate
these smaller ops into a full blown struct before use in the
core.

v1:
 - use struct assignment
 - put a full copy of the op in struct genl_dumpit_info
 - s/light/small/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
genetlink: reorg struct genl_family 2020-10-03T02:11:11+00:00 Jakub Kicinski kuba@kernel.org 2020-10-02T21:49:52+00:00 e5086736969880478abb2ac85ef8757ac6ce45bf There are holes and oversized members in struct genl_family. Before: /* size: 104, cachelines: 2, members: 16 */ After: /* size: 88, cachelines: 2, members: 16 */ The command field in struct genlmsghdr is a u8, so no point in the operation count being 32 bit. Also operation 0 is usually undefined, so we only need 255 entries. netnsok and parallel_ops are only ever initialized to true. We can grow the fields as needed, compiler should warn us if someone tries to assign larger constants. Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Johannes Berg <johannes@sipsolutions.net> Signed-off-by: David S. Miller <davem@davemloft.net> 
There are holes and oversized members in struct genl_family.

Before: /* size: 104, cachelines: 2, members: 16 */
After:  /* size:  88, cachelines: 2, members: 16 */

The command field in struct genlmsghdr is a u8, so no point
in the operation count being 32 bit. Also operation 0 is
usually undefined, so we only need 255 entries.

netnsok and parallel_ops are only ever initialized to true.

We can grow the fields as needed, compiler should warn us
if someone tries to assign larger constants.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Reviewed-by: Johannes Berg <johannes@sipsolutions.net>
Signed-off-by: David S. Miller <davem@davemloft.net>