groups: move code to kernel/groups.c
Move supplementary groups implementation to kernel/groups.c . kernel/sys.c already accumulated quite a few random stuff. Do strictly copy/paste + add required headers to compile. Compile-tested on many configs and archs. Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com> Cc: Ingo Molnar <mingo@elte.hu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Alexey Dobriyan
Linus Torvalds
Родитель
8b0b1db013
Коммит
30639b6af8
|
|
@ -11,6 +11,7 @@ obj-y = sched.o fork.o exec_domain.o panic.o printk.o \
|
|||
hrtimer.o rwsem.o nsproxy.o srcu.o semaphore.o \
|
||||
notifier.o ksysfs.o pm_qos_params.o sched_clock.o cred.o \
|
||||
async.o
|
||||
obj-y += groups.o
|
||||
|
||||
ifdef CONFIG_FUNCTION_TRACER
|
||||
# Do not trace debug files and internal ftrace files
|
||||
|
|
|
|||
|
|
@ -0,0 +1,288 @@
|
|||
/*
|
||||
* Supplementary group IDs
|
||||
*/
|
||||
#include <linux/cred.h>
|
||||
#include <linux/module.h>
|
||||
#include <linux/slab.h>
|
||||
#include <linux/security.h>
|
||||
#include <linux/syscalls.h>
|
||||
#include <asm/uaccess.h>
|
||||
|
||||
/* init to 2 - one for init_task, one to ensure it is never freed */
|
||||
struct group_info init_groups = { .usage = ATOMIC_INIT(2) };
|
||||
|
||||
struct group_info *groups_alloc(int gidsetsize)
|
||||
{
|
||||
struct group_info *group_info;
|
||||
int nblocks;
|
||||
int i;
|
||||
|
||||
nblocks = (gidsetsize + NGROUPS_PER_BLOCK - 1) / NGROUPS_PER_BLOCK;
|
||||
/* Make sure we always allocate at least one indirect block pointer */
|
||||
nblocks = nblocks ? : 1;
|
||||
group_info = kmalloc(sizeof(*group_info) + nblocks*sizeof(gid_t *), GFP_USER);
|
||||
if (!group_info)
|
||||
return NULL;
|
||||
group_info->ngroups = gidsetsize;
|
||||
group_info->nblocks = nblocks;
|
||||
atomic_set(&group_info->usage, 1);
|
||||
|
||||
if (gidsetsize <= NGROUPS_SMALL)
|
||||
group_info->blocks[0] = group_info->small_block;
|
||||
else {
|
||||
for (i = 0; i < nblocks; i++) {
|
||||
gid_t *b;
|
||||
b = (void *)__get_free_page(GFP_USER);
|
||||
if (!b)
|
||||
goto out_undo_partial_alloc;
|
||||
group_info->blocks[i] = b;
|
||||
}
|
||||
}
|
||||
return group_info;
|
||||
|
||||
out_undo_partial_alloc:
|
||||
while (--i >= 0) {
|
||||
free_page((unsigned long)group_info->blocks[i]);
|
||||
}
|
||||
kfree(group_info);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(groups_alloc);
|
||||
|
||||
void groups_free(struct group_info *group_info)
|
||||
{
|
||||
if (group_info->blocks[0] != group_info->small_block) {
|
||||
int i;
|
||||
for (i = 0; i < group_info->nblocks; i++)
|
||||
free_page((unsigned long)group_info->blocks[i]);
|
||||
}
|
||||
kfree(group_info);
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(groups_free);
|
||||
|
||||
/* export the group_info to a user-space array */
|
||||
static int groups_to_user(gid_t __user *grouplist,
|
||||
const struct group_info *group_info)
|
||||
{
|
||||
int i;
|
||||
unsigned int count = group_info->ngroups;
|
||||
|
||||
for (i = 0; i < group_info->nblocks; i++) {
|
||||
unsigned int cp_count = min(NGROUPS_PER_BLOCK, count);
|
||||
unsigned int len = cp_count * sizeof(*grouplist);
|
||||
|
||||
if (copy_to_user(grouplist, group_info->blocks[i], len))
|
||||
return -EFAULT;
|
||||
|
||||
grouplist += NGROUPS_PER_BLOCK;
|
||||
count -= cp_count;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* fill a group_info from a user-space array - it must be allocated already */
|
||||
static int groups_from_user(struct group_info *group_info,
|
||||
gid_t __user *grouplist)
|
||||
{
|
||||
int i;
|
||||
unsigned int count = group_info->ngroups;
|
||||
|
||||
for (i = 0; i < group_info->nblocks; i++) {
|
||||
unsigned int cp_count = min(NGROUPS_PER_BLOCK, count);
|
||||
unsigned int len = cp_count * sizeof(*grouplist);
|
||||
|
||||
if (copy_from_user(group_info->blocks[i], grouplist, len))
|
||||
return -EFAULT;
|
||||
|
||||
grouplist += NGROUPS_PER_BLOCK;
|
||||
count -= cp_count;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* a simple Shell sort */
|
||||
static void groups_sort(struct group_info *group_info)
|
||||
{
|
||||
int base, max, stride;
|
||||
int gidsetsize = group_info->ngroups;
|
||||
|
||||
for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1)
|
||||
; /* nothing */
|
||||
stride /= 3;
|
||||
|
||||
while (stride) {
|
||||
max = gidsetsize - stride;
|
||||
for (base = 0; base < max; base++) {
|
||||
int left = base;
|
||||
int right = left + stride;
|
||||
gid_t tmp = GROUP_AT(group_info, right);
|
||||
|
||||
while (left >= 0 && GROUP_AT(group_info, left) > tmp) {
|
||||
GROUP_AT(group_info, right) =
|
||||
GROUP_AT(group_info, left);
|
||||
right = left;
|
||||
left -= stride;
|
||||
}
|
||||
GROUP_AT(group_info, right) = tmp;
|
||||
}
|
||||
stride /= 3;
|
||||
}
|
||||
}
|
||||
|
||||
/* a simple bsearch */
|
||||
int groups_search(const struct group_info *group_info, gid_t grp)
|
||||
{
|
||||
unsigned int left, right;
|
||||
|
||||
if (!group_info)
|
||||
return 0;
|
||||
|
||||
left = 0;
|
||||
right = group_info->ngroups;
|
||||
while (left < right) {
|
||||
unsigned int mid = (left+right)/2;
|
||||
int cmp = grp - GROUP_AT(group_info, mid);
|
||||
if (cmp > 0)
|
||||
left = mid + 1;
|
||||
else if (cmp < 0)
|
||||
right = mid;
|
||||
else
|
||||
return 1;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* set_groups - Change a group subscription in a set of credentials
|
||||
* @new: The newly prepared set of credentials to alter
|
||||
* @group_info: The group list to install
|
||||
*
|
||||
* Validate a group subscription and, if valid, insert it into a set
|
||||
* of credentials.
|
||||
*/
|
||||
int set_groups(struct cred *new, struct group_info *group_info)
|
||||
{
|
||||
int retval;
|
||||
|
||||
retval = security_task_setgroups(group_info);
|
||||
if (retval)
|
||||
return retval;
|
||||
|
||||
put_group_info(new->group_info);
|
||||
groups_sort(group_info);
|
||||
get_group_info(group_info);
|
||||
new->group_info = group_info;
|
||||
return 0;
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(set_groups);
|
||||
|
||||
/**
|
||||
* set_current_groups - Change current's group subscription
|
||||
* @group_info: The group list to impose
|
||||
*
|
||||
* Validate a group subscription and, if valid, impose it upon current's task
|
||||
* security record.
|
||||
*/
|
||||
int set_current_groups(struct group_info *group_info)
|
||||
{
|
||||
struct cred *new;
|
||||
int ret;
|
||||
|
||||
new = prepare_creds();
|
||||
if (!new)
|
||||
return -ENOMEM;
|
||||
|
||||
ret = set_groups(new, group_info);
|
||||
if (ret < 0) {
|
||||
abort_creds(new);
|
||||
return ret;
|
||||
}
|
||||
|
||||
return commit_creds(new);
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(set_current_groups);
|
||||
|
||||
SYSCALL_DEFINE2(getgroups, int, gidsetsize, gid_t __user *, grouplist)
|
||||
{
|
||||
const struct cred *cred = current_cred();
|
||||
int i;
|
||||
|
||||
if (gidsetsize < 0)
|
||||
return -EINVAL;
|
||||
|
||||
/* no need to grab task_lock here; it cannot change */
|
||||
i = cred->group_info->ngroups;
|
||||
if (gidsetsize) {
|
||||
if (i > gidsetsize) {
|
||||
i = -EINVAL;
|
||||
goto out;
|
||||
}
|
||||
if (groups_to_user(grouplist, cred->group_info)) {
|
||||
i = -EFAULT;
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
out:
|
||||
return i;
|
||||
}
|
||||
|
||||
/*
|
||||
* SMP: Our groups are copy-on-write. We can set them safely
|
||||
* without another task interfering.
|
||||
*/
|
||||
|
||||
SYSCALL_DEFINE2(setgroups, int, gidsetsize, gid_t __user *, grouplist)
|
||||
{
|
||||
struct group_info *group_info;
|
||||
int retval;
|
||||
|
||||
if (!capable(CAP_SETGID))
|
||||
return -EPERM;
|
||||
if ((unsigned)gidsetsize > NGROUPS_MAX)
|
||||
return -EINVAL;
|
||||
|
||||
group_info = groups_alloc(gidsetsize);
|
||||
if (!group_info)
|
||||
return -ENOMEM;
|
||||
retval = groups_from_user(group_info, grouplist);
|
||||
if (retval) {
|
||||
put_group_info(group_info);
|
||||
return retval;
|
||||
}
|
||||
|
||||
retval = set_current_groups(group_info);
|
||||
put_group_info(group_info);
|
||||
|
||||
return retval;
|
||||
}
|
||||
|
||||
/*
|
||||
* Check whether we're fsgid/egid or in the supplemental group..
|
||||
*/
|
||||
int in_group_p(gid_t grp)
|
||||
{
|
||||
const struct cred *cred = current_cred();
|
||||
int retval = 1;
|
||||
|
||||
if (grp != cred->fsgid)
|
||||
retval = groups_search(cred->group_info, grp);
|
||||
return retval;
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(in_group_p);
|
||||
|
||||
int in_egroup_p(gid_t grp)
|
||||
{
|
||||
const struct cred *cred = current_cred();
|
||||
int retval = 1;
|
||||
|
||||
if (grp != cred->egid)
|
||||
retval = groups_search(cred->group_info, grp);
|
||||
return retval;
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(in_egroup_p);
|
||||
283
kernel/sys.c
283
kernel/sys.c
|
|
@ -1113,289 +1113,6 @@ out:
|
|||
return err;
|
||||
}
|
||||
|
||||
/*
|
||||
* Supplementary group IDs
|
||||
*/
|
||||
|
||||
/* init to 2 - one for init_task, one to ensure it is never freed */
|
||||
struct group_info init_groups = { .usage = ATOMIC_INIT(2) };
|
||||
|
||||
struct group_info *groups_alloc(int gidsetsize)
|
||||
{
|
||||
struct group_info *group_info;
|
||||
int nblocks;
|
||||
int i;
|
||||
|
||||
nblocks = (gidsetsize + NGROUPS_PER_BLOCK - 1) / NGROUPS_PER_BLOCK;
|
||||
/* Make sure we always allocate at least one indirect block pointer */
|
||||
nblocks = nblocks ? : 1;
|
||||
group_info = kmalloc(sizeof(*group_info) + nblocks*sizeof(gid_t *), GFP_USER);
|
||||
if (!group_info)
|
||||
return NULL;
|
||||
group_info->ngroups = gidsetsize;
|
||||
group_info->nblocks = nblocks;
|
||||
atomic_set(&group_info->usage, 1);
|
||||
|
||||
if (gidsetsize <= NGROUPS_SMALL)
|
||||
group_info->blocks[0] = group_info->small_block;
|
||||
else {
|
||||
for (i = 0; i < nblocks; i++) {
|
||||
gid_t *b;
|
||||
b = (void *)__get_free_page(GFP_USER);
|
||||
if (!b)
|
||||
goto out_undo_partial_alloc;
|
||||
group_info->blocks[i] = b;
|
||||
}
|
||||
}
|
||||
return group_info;
|
||||
|
||||
out_undo_partial_alloc:
|
||||
while (--i >= 0) {
|
||||
free_page((unsigned long)group_info->blocks[i]);
|
||||
}
|
||||
kfree(group_info);
|
||||
return NULL;
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(groups_alloc);
|
||||
|
||||
void groups_free(struct group_info *group_info)
|
||||
{
|
||||
if (group_info->blocks[0] != group_info->small_block) {
|
||||
int i;
|
||||
for (i = 0; i < group_info->nblocks; i++)
|
||||
free_page((unsigned long)group_info->blocks[i]);
|
||||
}
|
||||
kfree(group_info);
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(groups_free);
|
||||
|
||||
/* export the group_info to a user-space array */
|
||||
static int groups_to_user(gid_t __user *grouplist,
|
||||
const struct group_info *group_info)
|
||||
{
|
||||
int i;
|
||||
unsigned int count = group_info->ngroups;
|
||||
|
||||
for (i = 0; i < group_info->nblocks; i++) {
|
||||
unsigned int cp_count = min(NGROUPS_PER_BLOCK, count);
|
||||
unsigned int len = cp_count * sizeof(*grouplist);
|
||||
|
||||
if (copy_to_user(grouplist, group_info->blocks[i], len))
|
||||
return -EFAULT;
|
||||
|
||||
grouplist += NGROUPS_PER_BLOCK;
|
||||
count -= cp_count;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* fill a group_info from a user-space array - it must be allocated already */
|
||||
static int groups_from_user(struct group_info *group_info,
|
||||
gid_t __user *grouplist)
|
||||
{
|
||||
int i;
|
||||
unsigned int count = group_info->ngroups;
|
||||
|
||||
for (i = 0; i < group_info->nblocks; i++) {
|
||||
unsigned int cp_count = min(NGROUPS_PER_BLOCK, count);
|
||||
unsigned int len = cp_count * sizeof(*grouplist);
|
||||
|
||||
if (copy_from_user(group_info->blocks[i], grouplist, len))
|
||||
return -EFAULT;
|
||||
|
||||
grouplist += NGROUPS_PER_BLOCK;
|
||||
count -= cp_count;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* a simple Shell sort */
|
||||
static void groups_sort(struct group_info *group_info)
|
||||
{
|
||||
int base, max, stride;
|
||||
int gidsetsize = group_info->ngroups;
|
||||
|
||||
for (stride = 1; stride < gidsetsize; stride = 3 * stride + 1)
|
||||
; /* nothing */
|
||||
stride /= 3;
|
||||
|
||||
while (stride) {
|
||||
max = gidsetsize - stride;
|
||||
for (base = 0; base < max; base++) {
|
||||
int left = base;
|
||||
int right = left + stride;
|
||||
gid_t tmp = GROUP_AT(group_info, right);
|
||||
|
||||
while (left >= 0 && GROUP_AT(group_info, left) > tmp) {
|
||||
GROUP_AT(group_info, right) =
|
||||
GROUP_AT(group_info, left);
|
||||
right = left;
|
||||
left -= stride;
|
||||
}
|
||||
GROUP_AT(group_info, right) = tmp;
|
||||
}
|
||||
stride /= 3;
|
||||
}
|
||||
}
|
||||
|
||||
/* a simple bsearch */
|
||||
int groups_search(const struct group_info *group_info, gid_t grp)
|
||||
{
|
||||
unsigned int left, right;
|
||||
|
||||
if (!group_info)
|
||||
return 0;
|
||||
|
||||
left = 0;
|
||||
right = group_info->ngroups;
|
||||
while (left < right) {
|
||||
unsigned int mid = (left+right)/2;
|
||||
int cmp = grp - GROUP_AT(group_info, mid);
|
||||
if (cmp > 0)
|
||||
left = mid + 1;
|
||||
else if (cmp < 0)
|
||||
right = mid;
|
||||
else
|
||||
return 1;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
/**
|
||||
* set_groups - Change a group subscription in a set of credentials
|
||||
* @new: The newly prepared set of credentials to alter
|
||||
* @group_info: The group list to install
|
||||
*
|
||||
* Validate a group subscription and, if valid, insert it into a set
|
||||
* of credentials.
|
||||
*/
|
||||
int set_groups(struct cred *new, struct group_info *group_info)
|
||||
{
|
||||
int retval;
|
||||
|
||||
retval = security_task_setgroups(group_info);
|
||||
if (retval)
|
||||
return retval;
|
||||
|
||||
put_group_info(new->group_info);
|
||||
groups_sort(group_info);
|
||||
get_group_info(group_info);
|
||||
new->group_info = group_info;
|
||||
return 0;
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(set_groups);
|
||||
|
||||
/**
|
||||
* set_current_groups - Change current's group subscription
|
||||
* @group_info: The group list to impose
|
||||
*
|
||||
* Validate a group subscription and, if valid, impose it upon current's task
|
||||
* security record.
|
||||
*/
|
||||
int set_current_groups(struct group_info *group_info)
|
||||
{
|
||||
struct cred *new;
|
||||
int ret;
|
||||
|
||||
new = prepare_creds();
|
||||
if (!new)
|
||||
return -ENOMEM;
|
||||
|
||||
ret = set_groups(new, group_info);
|
||||
if (ret < 0) {
|
||||
abort_creds(new);
|
||||
return ret;
|
||||
}
|
||||
|
||||
return commit_creds(new);
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(set_current_groups);
|
||||
|
||||
SYSCALL_DEFINE2(getgroups, int, gidsetsize, gid_t __user *, grouplist)
|
||||
{
|
||||
const struct cred *cred = current_cred();
|
||||
int i;
|
||||
|
||||
if (gidsetsize < 0)
|
||||
return -EINVAL;
|
||||
|
||||
/* no need to grab task_lock here; it cannot change */
|
||||
i = cred->group_info->ngroups;
|
||||
if (gidsetsize) {
|
||||
if (i > gidsetsize) {
|
||||
i = -EINVAL;
|
||||
goto out;
|
||||
}
|
||||
if (groups_to_user(grouplist, cred->group_info)) {
|
||||
i = -EFAULT;
|
||||
goto out;
|
||||
}
|
||||
}
|
||||
out:
|
||||
return i;
|
||||
}
|
||||
|
||||
/*
|
||||
* SMP: Our groups are copy-on-write. We can set them safely
|
||||
* without another task interfering.
|
||||
*/
|
||||
|
||||
SYSCALL_DEFINE2(setgroups, int, gidsetsize, gid_t __user *, grouplist)
|
||||
{
|
||||
struct group_info *group_info;
|
||||
int retval;
|
||||
|
||||
if (!capable(CAP_SETGID))
|
||||
return -EPERM;
|
||||
if ((unsigned)gidsetsize > NGROUPS_MAX)
|
||||
return -EINVAL;
|
||||
|
||||
group_info = groups_alloc(gidsetsize);
|
||||
if (!group_info)
|
||||
return -ENOMEM;
|
||||
retval = groups_from_user(group_info, grouplist);
|
||||
if (retval) {
|
||||
put_group_info(group_info);
|
||||
return retval;
|
||||
}
|
||||
|
||||
retval = set_current_groups(group_info);
|
||||
put_group_info(group_info);
|
||||
|
||||
return retval;
|
||||
}
|
||||
|
||||
/*
|
||||
* Check whether we're fsgid/egid or in the supplemental group..
|
||||
*/
|
||||
int in_group_p(gid_t grp)
|
||||
{
|
||||
const struct cred *cred = current_cred();
|
||||
int retval = 1;
|
||||
|
||||
if (grp != cred->fsgid)
|
||||
retval = groups_search(cred->group_info, grp);
|
||||
return retval;
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(in_group_p);
|
||||
|
||||
int in_egroup_p(gid_t grp)
|
||||
{
|
||||
const struct cred *cred = current_cred();
|
||||
int retval = 1;
|
||||
|
||||
if (grp != cred->egid)
|
||||
retval = groups_search(cred->group_info, grp);
|
||||
return retval;
|
||||
}
|
||||
|
||||
EXPORT_SYMBOL(in_egroup_p);
|
||||
|
||||
DECLARE_RWSEM(uts_sem);
|
||||
|
||||
SYSCALL_DEFINE1(newuname, struct new_utsname __user *, name)
|
||||
|
|
|
|||
Загрузка…
Ссылка в новой задаче