waitid(): Add missing access_ok() checks

Adds missing access_ok() checks.

CVE-2017-5123

Reported-by: Chris Salls <chrissalls5@gmail.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: Al Viro <viro@zeniv.linux.org.uk>
Fixes: 4c48abe91b ("waitid(): switch copyout of siginfo to unsafe_put_user()")
Cc: stable@kernel.org # 4.13
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Kees Cook 2017-10-09 11:36:52 -07:00 committed by Linus Torvalds
parent ff33952e4d
commit 96ca579a1e
1 changed files with 6 additions and 0 deletions

View File

@ -1610,6 +1610,9 @@ SYSCALL_DEFINE5(waitid, int, which, pid_t, upid, struct siginfo __user *,
if (!infop)
return err;
if (!access_ok(VERIFY_WRITE, infop, sizeof(*infop)))
goto Efault;
user_access_begin();
unsafe_put_user(signo, &infop->si_signo, Efault);
unsafe_put_user(0, &infop->si_errno, Efault);
@ -1735,6 +1738,9 @@ COMPAT_SYSCALL_DEFINE5(waitid,
if (!infop)
return err;
if (!access_ok(VERIFY_WRITE, infop, sizeof(*infop)))
goto Efault;
user_access_begin();
unsafe_put_user(signo, &infop->si_signo, Efault);
unsafe_put_user(0, &infop->si_errno, Efault);