diff options
Diffstat (limited to 'fs/binfmt_elf.c')
| -rw-r--r-- | fs/binfmt_elf.c | 23 |
1 files changed, 20 insertions, 3 deletions
diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c index f8a0b0efda44..53b6d624c7a9 100644 --- a/fs/binfmt_elf.c +++ b/fs/binfmt_elf.c @@ -140,6 +140,25 @@ static int padzero(unsigned long elf_bss) #define ELF_BASE_PLATFORM NULL #endif +/* + * Use get_random_int() to implement AT_RANDOM while avoiding depletion + * of the entropy pool. + */ +static void get_atrandom_bytes(unsigned char *buf, size_t nbytes) +{ + unsigned char *p = buf; + + while (nbytes) { + unsigned int random_variable; + size_t chunk = min(nbytes, sizeof(random_variable)); + + random_variable = get_random_int(); + memcpy(p, &random_variable, chunk); + p += chunk; + nbytes -= chunk; + } +} + static int create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec, unsigned long load_addr, unsigned long interp_load_addr) @@ -201,7 +220,7 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec, /* * Generate 16 random bytes for userspace PRNG seeding. */ - get_random_bytes(k_rand_bytes, sizeof(k_rand_bytes)); + get_atrandom_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))) @@ -738,8 +757,6 @@ static int load_elf_binary(struct linux_binprm *bprm) /* Do this so that we can load the interpreter, if need be. We will change some of these later */ - current->mm->free_area_cache = current->mm->mmap_base; - current->mm->cached_hole_size = 0; retval = setup_arg_pages(bprm, randomize_stack_top(STACK_TOP), executable_stack); if (retval < 0) { |