From nobody Fri Oct 03 17:13:04 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 4cdZxF4VkYz6BDLH; Fri, 03 Oct 2025 17:13:05 +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 4cdZxF2JXMz3P5g; Fri, 03 Oct 2025 17:13:05 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1759511585; 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=KcUJGJO2CIuefENcKeE5WMx+rQtIwovZjXKdMZry6ko=; b=dcCLDGNfx9WlkHbYgkppb88wYkRW64ncI6Jt1H+eFbS7BhQFPphb+TqtE1gUYrCeqKthoG lMLTwGZedXiRo9Zk3xQW4+03fnYp18xm5bna3nbMSWgJbw6/k1BQSnBWVjidjnPpjMmzpP caybTpjO/JSOfK95txkrjz1d5K6UhDdgtdMKL4tSs8G0o5SgvhGrTZ7eHcyLltcKQZODxp ZSqNptb5xE5puZ/9F/03HAflT8s4bvRdBBB1tqziP2FWFzc88Yu091dNc7SJ1h3Y0VkwwM +qED3TOvw04ed08+OznwnWuJVwo6/4pZZElYhP8F/hD9vse/AcRTXgWfNBTgkg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1759511585; 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=KcUJGJO2CIuefENcKeE5WMx+rQtIwovZjXKdMZry6ko=; b=bC2NQayxeBFPXuFIlYKw4C3uexF5spwNzTdlEuga7aiFPLuonUnde88e6H/tNiIZ7BT49L AazTD1Y0Wy+3jQpdxiJEqucD3WlcavRQEa76j4JtMn7A1bx9r78j4ETBksbsTst6SyUPLj q/Mj7xI6GP06o9jmtjrLtX1gjBkh7vNf7A1RGV50yQlK+ogzoJ56B9C3kH89TmnAfEi7Kw 6AmX0stjd0lsPJ+msufXqswCmCvlpMGqAGof2rbJUtIzfyoa/hozwIObg2FZAq4sYaBJqI Mq3czN7GH0grLzvDWRxeVtlNP6eOFvzVOhHJqby5T0xWYSNm6cwQv1JMC9lJFA== ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1759511585; a=rsa-sha256; cv=none; b=RqsqCzpo1tOlk2OlSz6F1DH+MA2Nh6DS6exqErUjROs9Fn9kvybXnTily6iPk/OBEO8KJI /DOFai8bi5WpaNeSfNpTsdBLqH8QzCXBNwRuuRUd0XIBFQ/wPCUHPTR8owpu9CXuRDEv9e hJqNGekFkz/JeNZF4XXUIWF3ZCMo6Z9xLu9NZRmLKVnsame6ZZNMH60Pi9gDpn+ZrsMhrP 2EAo1PhdOVOMaq8D1VTRMScXqVwt5sAR5aiRqdmWsoHpCLb33kamao65qKiCIxmr6T6BP9 AP8GWRdebFw7ARA4ARFkMI7uzHphkVYSzPuhKPVQAgCHIF7UYA3GV59vCHYS1g== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (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 did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4cdZxF0kQjz1416; Fri, 03 Oct 2025 17:13:05 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.18.1/8.18.1) with ESMTP id 593HD5k9002823; Fri, 3 Oct 2025 17:13:05 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.18.1/8.18.1/Submit) id 593HD4Z1002820; Fri, 3 Oct 2025 17:13:04 GMT (envelope-from git) Date: Fri, 3 Oct 2025 17:13:04 GMT Message-Id: <202510031713.593HD4Z1002820@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-main@FreeBSD.org From: John Baldwin Subject: git: dfd7d1610aeb - main - filedesc: Close race between fcntl(F_SETFL) and ioctl(FIONBIO/FIOASYNC) 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: jhb X-Git-Repository: src X-Git-Refname: refs/heads/main X-Git-Reftype: branch X-Git-Commit: dfd7d1610aeb654aafcaa8cf77b75fc5c7d60250 Auto-Submitted: auto-generated The branch main has been updated by jhb: URL: https://cgit.FreeBSD.org/src/commit/?id=dfd7d1610aeb654aafcaa8cf77b75fc5c7d60250 commit dfd7d1610aeb654aafcaa8cf77b75fc5c7d60250 Author: John Baldwin AuthorDate: 2025-10-03 16:43:30 +0000 Commit: John Baldwin CommitDate: 2025-10-03 16:43:30 +0000 filedesc: Close race between fcntl(F_SETFL) and ioctl(FIONBIO/FIOASYNC) - Use the recently-added fsetfl_lock/unlock API to synchronize direct FIONBIO and FIOASYNC ioctls with fcntl(F_SETFL). - While here, skip calling the underlying ioctl if the flag's current state matches the requested state. - Also while here, only update the flag state if the underlying ioctl succeeds. This fixes a bug where the flags represented the new state even if the underlying ioctl failed. A test is added for this last case that a failing FIOASYNC on /dev/null doesn't result in setting O_ASYNC in the file flags. Reviewed by: kib Differential Revision: https://reviews.freebsd.org/D52721 --- sys/kern/sys_generic.c | 36 +++++++++++++++++++++--------------- tests/sys/file/fcntlflags_test.c | 27 +++++++++++++++++++++++++++ 2 files changed, 48 insertions(+), 15 deletions(-) diff --git a/sys/kern/sys_generic.c b/sys/kern/sys_generic.c index 5606b36f772f..7d666da9f88b 100644 --- a/sys/kern/sys_generic.c +++ b/sys/kern/sys_generic.c @@ -729,7 +729,7 @@ kern_ioctl(struct thread *td, int fd, u_long com, caddr_t data) { struct file *fp; struct filedesc *fdp; - int error, tmp, locked; + int error, f_flag, tmp, locked; AUDIT_ARG_FD(fd); AUDIT_ARG_CMD(com); @@ -782,30 +782,36 @@ kern_ioctl(struct thread *td, int fd, u_long com, caddr_t data) goto out; } + f_flag = 0; switch (com) { case FIONCLEX: fdp->fd_ofiles[fd].fde_flags &= ~UF_EXCLOSE; - goto out; + break; case FIOCLEX: fdp->fd_ofiles[fd].fde_flags |= UF_EXCLOSE; - goto out; - case FIONBIO: - if ((tmp = *(int *)data)) - atomic_set_int(&fp->f_flag, FNONBLOCK); - else - atomic_clear_int(&fp->f_flag, FNONBLOCK); - data = (void *)&tmp; break; + case FIONBIO: case FIOASYNC: - if ((tmp = *(int *)data)) - atomic_set_int(&fp->f_flag, FASYNC); - else - atomic_clear_int(&fp->f_flag, FASYNC); - data = (void *)&tmp; + f_flag = com == FIONBIO ? FNONBLOCK : FASYNC; + tmp = *(int *)data; + fsetfl_lock(fp); + if (((fp->f_flag & f_flag) != 0) != (tmp != 0)) { + error = fo_ioctl(fp, com, (void *)&tmp, td->td_ucred, + td); + if (error == 0) { + if (tmp != 0) + atomic_set_int(&fp->f_flag, f_flag); + else + atomic_clear_int(&fp->f_flag, f_flag); + } + } + fsetfl_unlock(fp); + break; + default: + error = fo_ioctl(fp, com, data, td->td_ucred, td); break; } - error = fo_ioctl(fp, com, data, td->td_ucred, td); out: switch (locked) { case LA_XLOCKED: diff --git a/tests/sys/file/fcntlflags_test.c b/tests/sys/file/fcntlflags_test.c index 009bb87371a1..15a18c113c4a 100644 --- a/tests/sys/file/fcntlflags_test.c +++ b/tests/sys/file/fcntlflags_test.c @@ -24,6 +24,7 @@ * SUCH DAMAGE. */ +#include #include #include #include @@ -95,12 +96,38 @@ ATF_TC_BODY(exec_only_sh, tc) basic_tests("/bin/sh", O_EXEC, "O_EXEC"); } +ATF_TC_WITHOUT_HEAD(fioasync_dev_null); +ATF_TC_BODY(fioasync_dev_null, tc) +{ + int fd, flags1, flags2, val; + + fd = open("/dev/null", O_RDONLY); + ATF_REQUIRE_MSG(fd != -1, "open(\"/dev/null\") failed: %s", + strerror(errno)); + + flags1 = fcntl(fd, F_GETFL); + ATF_REQUIRE_MSG(flags1 != -1, "fcntl(F_GETFL) (1) failed: %s", + strerror(errno)); + ATF_REQUIRE((flags1 & O_ASYNC) == 0); + + val = 1; + ATF_REQUIRE_ERRNO(EINVAL, ioctl(fd, FIOASYNC, &val) == -1); + + flags2 = fcntl(fd, F_GETFL); + ATF_REQUIRE_MSG(flags2 != -1, "fcntl(F_GETFL) (2) failed: %s", + strerror(errno)); + ATF_REQUIRE_INTEQ(flags1, flags2); + + (void)close(fd); +} + ATF_TP_ADD_TCS(tp) { ATF_TP_ADD_TC(tp, read_only_null); ATF_TP_ADD_TC(tp, write_only_null); ATF_TP_ADD_TC(tp, read_write_null); ATF_TP_ADD_TC(tp, exec_only_sh); + ATF_TP_ADD_TC(tp, fioasync_dev_null); return (atf_no_error()); }