Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit d2d56c5f authored by Marcel Holtmann's avatar Marcel Holtmann Committed by Linus Torvalds
Browse files

Reset current->pdeath_signal on SUID binary execution 

This fixes a vulnerability in the "parent process death signal"
implementation discoverd by Wojciech Purczynski of COSEINC PTE Ltd.
and iSEC Security Research.

http://marc.info/?l=bugtraq&m=118711306802632&w=2



Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent 28e8351a

fs/exec.c

+9 −4
Original line number Diff line number Diff line
@@ -1084,8 +1084,11 @@ int flush_old_exec(struct linux_binprm * bprm) 
	 */

	current->mm->task_size = TASK_SIZE;



	if (bprm->e_uid != current->euid || bprm->e_gid != current->egid || 

	    file_permission(bprm->file, MAY_READ) ||

	if (bprm->e_uid != current->euid || bprm->e_gid != current->egid) {

		suid_keys(current);

		set_dumpable(current->mm, suid_dumpable);

		current->pdeath_signal = 0;

	} else if (file_permission(bprm->file, MAY_READ) ||

			(bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP)) {

		suid_keys(current);

		set_dumpable(current->mm, suid_dumpable);
@@ -1177,8 +1180,10 @@ void compute_creds(struct linux_binprm *bprm) 
{

	int unsafe;



	if (bprm->e_uid != current->uid)

	if (bprm->e_uid != current->uid) {

		suid_keys(current);

		current->pdeath_signal = 0;

	}

	exec_keys(current);



	task_lock(current);