Topic: struct group_info init_groups = { .usage = ATOMIC_INIT(2) };
Falco !a7Q.SWNEJw started this discussion 11 years ago #32,101
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;
[/i][/i][/i](Edited 11 years later by a moderator.)
Anonymous B joined in and replied with this 11 years ago, 1 minute later[^] [v] #449,826
Elite hacker!(Edited 11 years later by a moderator.)
HaikerensGuide !dBGi/iH4eY joined in and replied with this 11 years ago, 5 minutes later, 6 minutes after the original post[^] [v] #449,827
Anonymous B replied with this 11 years ago, 2 minutes later, 9 minutes after the original post[^] [v] #449,829
Anonymous D joined in and replied with this 11 years ago, 7 hours later, 8 hours after the original post[^] [v] #449,851
use a code tag
Anonymous E joined in and replied with this 11 years ago, 13 hours later, 21 hours after the original post[^] [v] #449,912
that shit is ugly