From: Wang Yan Date: Mon, 22 Jun 2026 10:33:48 +0000 (+0800) Subject: time: Fix off-by-one in compat settimeofday() usec validation X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=269f2b43fae692d1f3988c9f888a6301aa537b82;p=thirdparty%2Flinux.git time: Fix off-by-one in compat settimeofday() usec validation The compat version of settimeofday() uses '>' instead of '>=' when validating tv_usec against USEC_PER_SEC, allowing the value 1000000 to pass the check. After the subsequent conversion to nanoseconds (tv_nsec *= NSEC_PER_USEC), this results in tv_nsec == NSEC_PER_SEC, which violates the timespec invariant that tv_nsec must be strictly less than NSEC_PER_SEC. The native settimeofday() was already fixed in commit ce4abda5e126 ("time: Fix off-by-one in settimeofday() usec validation"), but the compat counterpart was missed. Fix it by using '>=' to reject tv_usec values outside the valid range [0, USEC_PER_SEC - 1]. Fixes: 5e0fb1b57bea ("y2038: time: avoid timespec usage in settimeofday()") Signed-off-by: Wang Yan Signed-off-by: Thomas Gleixner Acked-by: Arnd Bergmann Cc: stable@vger.kernel.org Link: https://patch.msgid.link/20260622103348.120255-1-wangyan01@kylinos.cn --- diff --git a/kernel/time/time.c b/kernel/time/time.c index 771cef87ad3b0..0dd63a91e7c58 100644 --- a/kernel/time/time.c +++ b/kernel/time/time.c @@ -251,7 +251,7 @@ COMPAT_SYSCALL_DEFINE2(settimeofday, struct old_timeval32 __user *, tv, get_user(new_ts.tv_nsec, &tv->tv_usec)) return -EFAULT; - if (new_ts.tv_nsec > USEC_PER_SEC || new_ts.tv_nsec < 0) + if (new_ts.tv_nsec >= USEC_PER_SEC || new_ts.tv_nsec < 0) return -EINVAL; new_ts.tv_nsec *= NSEC_PER_USEC;