include/uapi/linux/xfrm.h: Fix XFRM_MSG_MAPPING ABI breakage

Commit 2d151d3907 ("xfrm: Add possibility to set the default to block
if we have no policy") broke ABI by changing the value of the XFRM_MSG_MAPPING
enum item, thus also evading the build-time check
in security/selinux/nlmsgtab.c:selinux_nlmsg_lookup for presence of proper
security permission checks in nlmsg_xfrm_perms.  Fix it by placing
XFRM_MSG_SETDEFAULT/XFRM_MSG_GETDEFAULT to the end of the enum, right before
__XFRM_MSG_MAX, and updating the nlmsg_xfrm_perms accordingly.

Fixes: 2d151d3907 ("xfrm: Add possibility to set the default to block if we have no policy")
References: https://lore.kernel.org/netdev/20210901151402.GA2557@altlinux.org/
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Acked-by: Antony Antony <antony.antony@secunet.com>
Acked-by: Nicolas Dichtel <nicolas.dichtel@6wind.com>
Signed-off-by: Steffen Klassert <steffen.klassert@secunet.com>
This commit is contained in:
Eugene Syromiatnikov 2021-09-12 14:22:34 +02:00 коммит произвёл Steffen Klassert
Родитель 3c10ffddc6
Коммит 844f7eaaed
2 изменённых файлов: 6 добавлений и 4 удалений

Просмотреть файл

@ -213,13 +213,13 @@ enum {
XFRM_MSG_GETSPDINFO,
#define XFRM_MSG_GETSPDINFO XFRM_MSG_GETSPDINFO
XFRM_MSG_MAPPING,
#define XFRM_MSG_MAPPING XFRM_MSG_MAPPING
XFRM_MSG_SETDEFAULT,
#define XFRM_MSG_SETDEFAULT XFRM_MSG_SETDEFAULT
XFRM_MSG_GETDEFAULT,
#define XFRM_MSG_GETDEFAULT XFRM_MSG_GETDEFAULT
XFRM_MSG_MAPPING,
#define XFRM_MSG_MAPPING XFRM_MSG_MAPPING
__XFRM_MSG_MAX
};
#define XFRM_MSG_MAX (__XFRM_MSG_MAX - 1)

Просмотреть файл

@ -126,6 +126,8 @@ static const struct nlmsg_perm nlmsg_xfrm_perms[] =
{ XFRM_MSG_NEWSPDINFO, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_GETSPDINFO, NETLINK_XFRM_SOCKET__NLMSG_READ },
{ XFRM_MSG_MAPPING, NETLINK_XFRM_SOCKET__NLMSG_READ },
{ XFRM_MSG_SETDEFAULT, NETLINK_XFRM_SOCKET__NLMSG_WRITE },
{ XFRM_MSG_GETDEFAULT, NETLINK_XFRM_SOCKET__NLMSG_READ },
};
static const struct nlmsg_perm nlmsg_audit_perms[] =
@ -189,7 +191,7 @@ int selinux_nlmsg_lookup(u16 sclass, u16 nlmsg_type, u32 *perm)
* structures at the top of this file with the new mappings
* before updating the BUILD_BUG_ON() macro!
*/
BUILD_BUG_ON(XFRM_MSG_MAX != XFRM_MSG_MAPPING);
BUILD_BUG_ON(XFRM_MSG_MAX != XFRM_MSG_GETDEFAULT);
err = nlmsg_perm(nlmsg_type, perm, nlmsg_xfrm_perms,
sizeof(nlmsg_xfrm_perms));
break;