Commit aa4bf44d authored by Christian Brauner's avatar Christian Brauner Committed by Eric W. Biederman
Browse files

userns: use union in {g,u}idmap struct 



- Add a struct containing two pointer to extents and wrap both the static extent
  array and the struct into a union. This is done in preparation for bumping the
  {g,u}idmap limits for user namespaces.
- Add brackets around anonymous union when using designated initializers to
  initialize members in order to please gcc <= 4.4.

Signed-off-by: default avatarChristian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: default avatarEric W. Biederman <ebiederm@xmission.com>
parent e19b205b

include/linux/user_namespace.h

+13 −5
Original line number Diff line number Diff line
@@ -12,13 +12,21 @@ 


#define UID_GID_MAP_MAX_EXTENTS 5



struct uid_gid_map {	/* 64 bytes -- 1 cache line */

	u32 nr_extents;

struct uid_gid_extent {

	u32 first;

	u32 lower_first;

	u32 count;

	} extent[UID_GID_MAP_MAX_EXTENTS];

};



struct uid_gid_map {	/* 64 bytes -- 1 cache line */

	u32 nr_extents;

	union {

		struct uid_gid_extent extent[UID_GID_MAP_MAX_EXTENTS];

		struct {

			struct uid_gid_extent *forward;

			struct uid_gid_extent *reverse;

		};

	};

};



#define USERNS_SETGROUPS_ALLOWED 1UL

kernel/user.c

+18 −12
Original line number Diff line number Diff line
@@ -26,28 +26,34 @@ 
struct user_namespace init_user_ns = {

	.uid_map = {

		.nr_extents = 1,

		{

			.extent[0] = {

				.first = 0,

				.lower_first = 0,

				.count = 4294967295U,

			},

		},

	},

	.gid_map = {

		.nr_extents = 1,

		{

			.extent[0] = {

				.first = 0,

				.lower_first = 0,

				.count = 4294967295U,

			},

		},

	},

	.projid_map = {

		.nr_extents = 1,

		{

			.extent[0] = {

				.first = 0,

				.lower_first = 0,

				.count = 4294967295U,

			},

		},

	},

	.count = ATOMIC_INIT(3),

	.owner = GLOBAL_ROOT_UID,

	.group = GLOBAL_ROOT_GID,

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