From nobody Thu Dec 18 19:47:19 2025 X-Original-To: dev-commits-src-main@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4dXLm80cwCz6LdcV for ; Thu, 18 Dec 2025 19:47:20 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "R12" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4dXLm76jKjz3Gtc for ; Thu, 18 Dec 2025 19:47:19 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1766087239; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=JIBkL+A8iVAmupEv2RO2yqsJlL9WLYnNeNDy8lGzRII=; b=WpIiB721I1jGkn2mFkBy9ZQ5Y+anDcaKK6eA4DLZcI1QePrVlhEC1qSyaQP8H8Tm+JBJAI N5gf5R79wsdWstzJmNOgy+8iQRUvSLNiDVgCuAJvpaNM37DnZL3YjT7zfy7xJkU81hLZvO 81hNLYxEp7rsC+q9FCKoOOLuNYKblefxjHrti5wo1UbsMFpyQqdLP5jQgdXByeI/DBXFhM ZIgdKWHCZwkIASvMb8jT1/GrcjoXR1T1mObpk+anXPIQVpUGlY+6gMmdLvSiuWwRAKyE0Y hdB6BcHlK6wDybcpMPYIemPN9BzOq25u+i3ZlDJYZHbN2xbVijZhuyX7VPf0yg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1766087239; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=JIBkL+A8iVAmupEv2RO2yqsJlL9WLYnNeNDy8lGzRII=; b=hesNpJk19kS2nBQM5MiHl0HsZvcGjLZJjkVxVyFoOUT4ulNl7kn9tVQkeKqWW0JAeUGubg xLHkAYDsVZzSTxynqD10FPvdC1SH/e7Pi8AGdpYKx/q5/AAp5UP5GUhD2UEfWKIzYmQJWG eOSL6RthBRI0UbWblcf3sDuozeZE6Ca+9erYKg/2YaYAP+q27YeWuCorSGY9aLjpMG/5js GneXLMQMDFjgiWQHQKYhPNFBxSYyGP8PqL6ZwLIBNftvIYBFCMmU7zifva5J3maDvth5Tm Y6XAAwOpwGqPegc8w9g/Bakw+R/wMoBkenGFKU4SL2Ewi30OAps8nqqPsOe5Fw== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1766087239; a=rsa-sha256; cv=none; b=CNvJgAtBV9SmQgINiWonN89+mvVs2q17QkBWCq+4SR4xxOF2wmXN8Fj3H25f9540j7/k8k GVlIsrjcDP4Kdo9PMKx1P8uD6h96bq9VIpInEyAm1FyzYeBR4Tk4eC2eXuHq0/Dv0tRoAd M6p0Z8M38xM0q44uTefdRnLHGVz+roLnT+hinFjxB5WsPN3IQipZExGmTSd19XPrKB4w6v 8lxaoqs/jm/psO9Ai+bvvG18DK6oBwH0DwPM6jajnI+uB0RYuT1BJOKJfF0G5EuJCby5US cn3RxBLncELEWAkZXxL3E2vOjeNsp6V7Z4l2oFIgF2oB1WTq1cBqeMrcHGEp7A== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4dXLm75xWXzsMn for ; Thu, 18 Dec 2025 19:47:19 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 3731a by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Thu, 18 Dec 2025 19:47:19 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: Mark Johnston Subject: git: 93811883500b - main - armv8rng: Fix an inverted test in random_rndr_read_one() List-Id: Commit messages for the main branch of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-main List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-main@freebsd.org Sender: owner-dev-commits-src-main@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: 93811883500b99f9f1fb4ffd6e764226d37dcfd0 Auto-Submitted: auto-generated Date: Thu, 18 Dec 2025 19:47:19 +0000 Message-Id: <69445a47.3731a.1226cb3@gitrepo.freebsd.org> The branch main has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=93811883500b99f9f1fb4ffd6e764226d37dcfd0 commit 93811883500b99f9f1fb4ffd6e764226d37dcfd0 Author: Mark Johnston AuthorDate: 2025-12-18 14:17:20 +0000 Commit: Mark Johnston CommitDate: 2025-12-18 19:46:42 +0000 armv8rng: Fix an inverted test in random_rndr_read_one() If we get a random number, the NZCV is set to 0b0000. Then "cset %w1, ne" will test whether Z == 0 and set %w1 to 1 if so. More specifically, "cset %w1, ne" maps to "csinc %w1, wzr, wzr, eq", which stores 0 in %w1 when NZCV == 0b0100 and 1 otherwise. Thus, on a successful read we expect ret != 0, so the loop condition needs to be fixed. In practice this means that we would end up trying to fetch entropy up to ten times in a row. If all attempts are successful, the last will be returned, otherwise no entropy will be returned. Reported by: Kevin Day Reviewed by: andrew Fixes: 9eecef052155 ("Add an Armv8 rndr random number provider") MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D54259 --- sys/dev/random/armv8rng.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/sys/dev/random/armv8rng.c b/sys/dev/random/armv8rng.c index 524d80317681..9573c09aa77a 100644 --- a/sys/dev/random/armv8rng.c +++ b/sys/dev/random/armv8rng.c @@ -64,7 +64,7 @@ random_rndr_read_one(u_long *buf) /* 1 on success, 0 on failure */ "cset %w1, ne\n" : "=&r" (val), "=&r"(ret) :: "cc"); - } while (ret != 0 && --loop > 0); + } while (ret == 0 && --loop > 0); if (ret != 0) *buf = val;