1 files changed, 25 insertions, 9 deletions

diff --git a/fs/binfmt_elf.c b/fs/binfmt_elf.c
index 8fcfa398d350..e3ff2b9e602f 100644
--- a/fs/binfmt_elf.c
+++ b/fs/binfmt_elf.c
@@ -152,12 +152,14 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
         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;
-        struct task_struct *tsk = current;
+        const struct cred *cred = current_cred();
         struct vm_area_struct *vma;
 
         /*
@@ -196,6 +198,15 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
                         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 */
@@ -223,11 +234,12 @@ create_elf_tables(struct linux_binprm *bprm, struct elfhdr *exec,
         NEW_AUX_ENT(AT_BASE, interp_load_addr);
         NEW_AUX_ENT(AT_FLAGS, 0);
         NEW_AUX_ENT(AT_ENTRY, exec->e_entry);
-        NEW_AUX_ENT(AT_UID, tsk->uid);
-        NEW_AUX_ENT(AT_EUID, tsk->euid);
-        NEW_AUX_ENT(AT_GID, tsk->gid);
-        NEW_AUX_ENT(AT_EGID, tsk->egid);
+        NEW_AUX_ENT(AT_UID, cred->uid);
+        NEW_AUX_ENT(AT_EUID, cred->euid);
+        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,
@@ -949,14 +961,14 @@ static int load_elf_binary(struct linux_binprm *bprm, struct pt_regs *regs)
         set_binfmt(&elf_format);
 
 #ifdef ARCH_HAS_SETUP_ADDITIONAL_PAGES
-        retval = arch_setup_additional_pages(bprm, executable_stack);
+        retval = arch_setup_additional_pages(bprm, !!elf_interpreter);
         if (retval < 0) {
                 send_sig(SIGKILL, current, 0);
                 goto out;
         }
 #endif /* ARCH_HAS_SETUP_ADDITIONAL_PAGES */
 
-        compute_creds(bprm);
+        install_exec_creds(bprm);
         current->flags &= ~PF_FORKNOEXEC;
         retval = create_elf_tables(bprm, &loc->elf_ex,
                           load_addr, interp_load_addr);
@@ -1361,6 +1373,7 @@ static void fill_prstatus(struct elf_prstatus *prstatus,
 static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
                        struct mm_struct *mm)
 {
+        const struct cred *cred;
         unsigned int i, len;
         
         /* first copy the parameters from user space */
@@ -1388,8 +1401,11 @@ static int fill_psinfo(struct elf_prpsinfo *psinfo, struct task_struct *p,
         psinfo->pr_zomb = psinfo->pr_sname == 'Z';
         psinfo->pr_nice = task_nice(p);
         psinfo->pr_flag = p->flags;
-        SET_UID(psinfo->pr_uid, p->uid);
-        SET_GID(psinfo->pr_gid, p->gid);
+        rcu_read_lock();
+        cred = __task_cred(p);
+        SET_UID(psinfo->pr_uid, cred->uid);
+        SET_GID(psinfo->pr_gid, cred->gid);
+        rcu_read_unlock();
         strncpy(psinfo->pr_fname, p->comm, sizeof(psinfo->pr_fname));
         
         return 0;