diff options
| author | Ido Schimmel <idosch@nvidia.com> | 2023-12-20 17:43:58 +0200 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2023-12-29 08:43:59 +0000 |
| commit | cd4d7263d58ab98fd4dee876776e4da6c328faa3 (patch) | |
| tree | 3f8d29bd2988c6daa7f27f90857c5a640b9a7b73 /include/net | |
| parent | f732ba4ac9f3626e235cc33a4f1756f17884dd32 (diff) | |
genetlink: Use internal flags for multicast groups
As explained in commit e03781879a0d ("drop_monitor: Require
'CAP_SYS_ADMIN' when joining "events" group"), the "flags" field in the
multicast group structure reuses uAPI flags despite the field not being
exposed to user space. This makes it impossible to extend its use
without adding new uAPI flags, which is inappropriate for internal
kernel checks.
Solve this by adding internal flags (i.e., "GENL_MCAST_*") and convert
the existing users to use them instead of the uAPI flags.
Tested using the reproducers in commit 44ec98ea5ea9 ("psample: Require
'CAP_NET_ADMIN' when joining "packets" group") and commit e03781879a0d
("drop_monitor: Require 'CAP_SYS_ADMIN' when joining "events" group").
No functional changes intended.
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Mat Martineau <martineau@kernel.org>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'include/net')
| -rw-r--r-- | include/net/genetlink.h | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/include/net/genetlink.h b/include/net/genetlink.h index 85c63d4f16dd..e61469129402 100644 --- a/include/net/genetlink.h +++ b/include/net/genetlink.h @@ -8,16 +8,19 @@ #define GENLMSG_DEFAULT_SIZE (NLMSG_DEFAULT_SIZE - GENL_HDRLEN) +/* Binding to multicast group requires %CAP_NET_ADMIN */ +#define GENL_MCAST_CAP_NET_ADMIN BIT(0) +/* Binding to multicast group requires %CAP_SYS_ADMIN */ +#define GENL_MCAST_CAP_SYS_ADMIN BIT(1) + /** * struct genl_multicast_group - generic netlink multicast group * @name: name of the multicast group, names are per-family - * @flags: GENL_* flags (%GENL_ADMIN_PERM or %GENL_UNS_ADMIN_PERM) - * @cap_sys_admin: whether %CAP_SYS_ADMIN is required for binding + * @flags: GENL_MCAST_* flags */ struct genl_multicast_group { char name[GENL_NAMSIZ]; u8 flags; - u8 cap_sys_admin:1; }; struct genl_split_ops; |