diff options
Diffstat (limited to 'fs/exec.c')
| -rw-r--r-- | fs/exec.c | 47 |
1 files changed, 37 insertions, 10 deletions
diff --git a/fs/exec.c b/fs/exec.c index 9a1d9f0a60ab..52c9e2ff6e6b 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -1139,7 +1139,7 @@ void setup_new_exec(struct linux_binprm * bprm) /* This is the point of no return */ current->sas_ss_sp = current->sas_ss_size = 0; - if (current_euid() == current_uid() && current_egid() == current_gid()) + if (uid_eq(current_euid(), current_uid()) && gid_eq(current_egid(), current_gid())) set_dumpable(current->mm, 1); else set_dumpable(current->mm, suid_dumpable); @@ -1153,8 +1153,8 @@ void setup_new_exec(struct linux_binprm * bprm) current->mm->task_size = TASK_SIZE; /* install the new credentials */ - if (bprm->cred->uid != current_euid() || - bprm->cred->gid != current_egid()) { + if (!uid_eq(bprm->cred->uid, current_euid()) || + !gid_eq(bprm->cred->gid, current_egid())) { current->pdeath_signal = 0; } else { would_dump(bprm, bprm->file); @@ -1245,6 +1245,13 @@ static int check_unsafe_exec(struct linux_binprm *bprm) bprm->unsafe |= LSM_UNSAFE_PTRACE; } + /* + * This isn't strictly necessary, but it makes it harder for LSMs to + * mess up. + */ + if (current->no_new_privs) + bprm->unsafe |= LSM_UNSAFE_NO_NEW_PRIVS; + n_fs = 1; spin_lock(&p->fs->lock); rcu_read_lock(); @@ -1288,11 +1295,15 @@ int prepare_binprm(struct linux_binprm *bprm) bprm->cred->euid = current_euid(); bprm->cred->egid = current_egid(); - if (!(bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID)) { + if (!(bprm->file->f_path.mnt->mnt_flags & MNT_NOSUID) && + !current->no_new_privs) { /* Set-uid? */ if (mode & S_ISUID) { + if (!kuid_has_mapping(bprm->cred->user_ns, inode->i_uid)) + return -EPERM; bprm->per_clear |= PER_CLEAR_ON_SETID; bprm->cred->euid = inode->i_uid; + } /* Set-gid? */ @@ -1302,6 +1313,8 @@ int prepare_binprm(struct linux_binprm *bprm) * executable. */ if ((mode & (S_ISGID | S_IXGRP)) == (S_ISGID | S_IXGRP)) { + if (!kgid_has_mapping(bprm->cred->user_ns, inode->i_gid)) + return -EPERM; bprm->per_clear |= PER_CLEAR_ON_SETID; bprm->cred->egid = inode->i_gid; } @@ -1371,7 +1384,7 @@ int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs) unsigned int depth = bprm->recursion_depth; int try,retval; struct linux_binfmt *fmt; - pid_t old_pid; + pid_t old_pid, old_vpid; retval = security_bprm_check(bprm); if (retval) @@ -1382,8 +1395,9 @@ int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs) return retval; /* Need to fetch pid before load_binary changes it */ + old_pid = current->pid; rcu_read_lock(); - old_pid = task_pid_nr_ns(current, task_active_pid_ns(current->parent)); + old_vpid = task_pid_nr_ns(current, task_active_pid_ns(current->parent)); rcu_read_unlock(); retval = -ENOENT; @@ -1406,7 +1420,7 @@ int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs) if (retval >= 0) { if (depth == 0) { trace_sched_process_exec(current, old_pid, bprm); - ptrace_event(PTRACE_EVENT_EXEC, old_pid); + ptrace_event(PTRACE_EVENT_EXEC, old_vpid); } put_binfmt(fmt); allow_write_access(bprm->file); @@ -1929,8 +1943,21 @@ static int coredump_wait(int exit_code, struct core_state *core_state) core_waiters = zap_threads(tsk, mm, core_state, exit_code); up_write(&mm->mmap_sem); - if (core_waiters > 0) + if (core_waiters > 0) { + struct core_thread *ptr; + wait_for_completion(&core_state->startup); + /* + * Wait for all the threads to become inactive, so that + * all the thread context (extended register state, like + * fpu etc) gets copied to the memory. + */ + ptr = core_state->dumper.next; + while (ptr != NULL) { + wait_task_inactive(ptr->task, 0); + ptr = ptr->next; + } + } return core_waiters; } @@ -2120,7 +2147,7 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs) if (__get_dumpable(cprm.mm_flags) == 2) { /* Setuid core dump mode */ flag = O_EXCL; /* Stop rewrite attacks */ - cred->fsuid = 0; /* Dump root private */ + cred->fsuid = GLOBAL_ROOT_UID; /* Dump root private */ } retval = coredump_wait(exit_code, &core_state); @@ -2221,7 +2248,7 @@ void do_coredump(long signr, int exit_code, struct pt_regs *regs) * Dont allow local users get cute and trick others to coredump * into their pre-created files. */ - if (inode->i_uid != current_fsuid()) + if (!uid_eq(inode->i_uid, current_fsuid())) goto close_fail; if (!cprm.file->f_op || !cprm.file->f_op->write) goto close_fail; |