elf_addr_t __user *sp;
elf_addr_t __user *u_platform;
elf_addr_t __user *u_base_platform;
+ elf_addr_t __user *u_rand_bytes;
const char *k_platform = ELF_PLATFORM;
const char *k_base_platform = ELF_BASE_PLATFORM;
+ unsigned char k_rand_bytes[16];
int items;
elf_addr_t *elf_info;
int ei_index = 0;
return -EFAULT;
}
+ /*
+ * Generate 16 random bytes for userspace PRNG seeding.
+ */
+ get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes));
+ u_rand_bytes = (elf_addr_t __user *)
+ STACK_ALLOC(p, sizeof(k_rand_bytes));
+ if (__copy_to_user(u_rand_bytes, k_rand_bytes, sizeof(k_rand_bytes)))
+ return -EFAULT;
+
/* Create the ELF interpreter info */
elf_info = (elf_addr_t *)current->mm->saved_auxv;
/* update AT_VECTOR_SIZE_BASE if the number of NEW_AUX_ENT() changes */
NEW_AUX_ENT(AT_GID, cred->gid);
NEW_AUX_ENT(AT_EGID, cred->egid);
NEW_AUX_ENT(AT_SECURE, security_bprm_secureexec(bprm));
+ NEW_AUX_ENT(AT_RANDOM, (elf_addr_t)(unsigned long)u_rand_bytes);
NEW_AUX_ENT(AT_EXECFN, bprm->exec);
if (k_platform) {
NEW_AUX_ENT(AT_PLATFORM,
* check for an ELF header. If we find one, dump the first page to
* aid in determining what was mapped here.
*/
- if (FILTER(ELF_HEADERS) && vma->vm_file != NULL && vma->vm_pgoff == 0) {
+ if (FILTER(ELF_HEADERS) &&
+ vma->vm_pgoff == 0 && (vma->vm_flags & VM_READ)) {
u32 __user *header = (u32 __user *) vma->vm_start;
u32 word;
+ mm_segment_t fs = get_fs();
/*
* Doing it this way gets the constant folded by GCC.
*/
magic.elfmag[EI_MAG1] = ELFMAG1;
magic.elfmag[EI_MAG2] = ELFMAG2;
magic.elfmag[EI_MAG3] = ELFMAG3;
- if (get_user(word, header) == 0 && word == magic.cmp)
+ /*
+ * Switch to the user "segment" for get_user(),
+ * then put back what elf_core_dump() had in place.
+ */
+ set_fs(USER_DS);
+ if (unlikely(get_user(word, header)))
+ word = 0;
+ set_fs(fs);
+ if (word == magic.cmp)
return PAGE_SIZE;
}