From: Michalis Pappas <michalis@unikraft.io>
Date: Wed, 30 Apr 2025 16:10:54 +0000 (+0200)
Subject: lib/posix-process/signal: Check canonical timeout on rt_sigtimedwait
X-Git-Url: http://xenbits.xensource.com/gitweb?a=commitdiff_plain;h=7abb246f70434de147448538b7d119abe9ac5e67;p=unikraft%2Funikraft.git

lib/posix-process/signal: Check canonical timeout on rt_sigtimedwait

Add check to ensure that the timeout value passed to rt_sigtimedwait()
is canonical.

Signed-off-by: Michalis Pappas <michalis@unikraft.io>
Reviewed-by: Sergiu Moga <sergiu@unikraft.io>
Reviewed-by: Andrei Tatar <andrei@unikraft.io>
Approved-by: Sergiu Moga <sergiu@unikraft.io>
GitHub-Closes: #1639
---

diff --git a/lib/posix-process/signal/rt_sigtimedwait.c b/lib/posix-process/signal/rt_sigtimedwait.c
index 4fe54762b..65119968d 100644
--- a/lib/posix-process/signal/rt_sigtimedwait.c
+++ b/lib/posix-process/signal/rt_sigtimedwait.c
@@ -46,11 +46,15 @@ UK_LLSYSCALL_R_DEFINE(int, rt_sigtimedwait,
 	if ((sig = pprocess_signal_next_pending_t(pthread)))
 		goto out;
 
-	if (timeout)
+	if (timeout) {
+		if (unlikely(!(uk_time_spec_canonical(timeout) &&
+			       uk_time_spec_positive(timeout))))
+			return -EINVAL;
 		uk_semaphore_down_to(&pthread->signal->pending_semaphore,
 				     uk_time_spec_to_nsec(timeout));
-	else
+	} else {
 		uk_semaphore_down(&pthread->signal->pending_semaphore);
+	}
 
 	if ((sig = pprocess_signal_next_pending_t(pthread)))
 		goto out;