From owner-svn-src-head@freebsd.org Thu Jun 20 23:07:23 2019 Return-Path: Delivered-To: svn-src-head@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id D167215CA211; Thu, 20 Jun 2019 23:07:22 +0000 (UTC) (envelope-from asomers@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) server-signature RSA-PSS (4096 bits) client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "Let's Encrypt Authority X3" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 53C566B804; Thu, 20 Jun 2019 23:07:22 +0000 (UTC) (envelope-from asomers@FreeBSD.org) Received: from repo.freebsd.org (repo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:0]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 2D1E31AC54; Thu, 20 Jun 2019 23:07:22 +0000 (UTC) (envelope-from asomers@FreeBSD.org) Received: from repo.freebsd.org ([127.0.1.37]) by repo.freebsd.org (8.15.2/8.15.2) with ESMTP id x5KN7MQ9002093; Thu, 20 Jun 2019 23:07:22 GMT (envelope-from asomers@FreeBSD.org) Received: (from asomers@localhost) by repo.freebsd.org (8.15.2/8.15.2/Submit) id x5KN7LLB002088; Thu, 20 Jun 2019 23:07:21 GMT (envelope-from asomers@FreeBSD.org) Message-Id: <201906202307.x5KN7LLB002088@repo.freebsd.org> X-Authentication-Warning: repo.freebsd.org: asomers set sender to asomers@FreeBSD.org using -f From: Alan Somers Date: Thu, 20 Jun 2019 23:07:21 +0000 (UTC) To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-head@freebsd.org Subject: svn commit: r349248 - in head/sys: fs/fifofs kern sys X-SVN-Group: head X-SVN-Commit-Author: asomers X-SVN-Commit-Paths: in head/sys: fs/fifofs kern sys X-SVN-Commit-Revision: 349248 X-SVN-Commit-Repository: base MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 53C566B804 X-Spamd-Bar: -- Authentication-Results: mx1.freebsd.org X-Spamd-Result: default: False [-2.95 / 15.00]; local_wl_from(0.00)[FreeBSD.org]; NEURAL_HAM_MEDIUM(-1.00)[-0.998,0]; NEURAL_HAM_SHORT(-0.96)[-0.956,0]; NEURAL_HAM_LONG(-1.00)[-1.000,0]; ASN(0.00)[asn:11403, ipnet:2610:1c1:1::/48, country:US] X-BeenThere: svn-src-head@freebsd.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: SVN commit messages for the src tree for head/-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 20 Jun 2019 23:07:23 -0000 Author: asomers Date: Thu Jun 20 23:07:20 2019 New Revision: 349248 URL: https://svnweb.freebsd.org/changeset/base/349248 Log: fcntl: fix overflow when setting F_READAHEAD VOP_READ and VOP_WRITE take the seqcount in blocks in a 16-bit field. However, fcntl allows you to set the seqcount in bytes to any nonnegative 31-bit value. The result can be a 16-bit overflow, which will be sign-extended in functions like ffs_read. Fix this by sanitizing the argument in kern_fcntl. As a matter of policy, limit to IO_SEQMAX rather than INT16_MAX. Also, fifos have overloaded the f_seqcount field for a completely different purpose ever since r238936. Formalize that by using a union type. Reviewed by: cem MFC after: 2 weeks Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D20710 Modified: head/sys/fs/fifofs/fifo_vnops.c head/sys/kern/kern_descrip.c head/sys/kern/sys_pipe.c head/sys/kern/vfs_vnops.c head/sys/sys/file.h Modified: head/sys/fs/fifofs/fifo_vnops.c ============================================================================== --- head/sys/fs/fifofs/fifo_vnops.c Thu Jun 20 22:21:42 2019 (r349247) +++ head/sys/fs/fifofs/fifo_vnops.c Thu Jun 20 23:07:20 2019 (r349248) @@ -174,7 +174,7 @@ fifo_open(ap) if (fip->fi_writers > 0) wakeup(&fip->fi_writers); } - fp->f_seqcount = fpipe->pipe_wgen - fip->fi_writers; + fp->f_pipegen = fpipe->pipe_wgen - fip->fi_writers; } if (ap->a_mode & FWRITE) { if ((ap->a_mode & O_NONBLOCK) && fip->fi_readers == 0) { Modified: head/sys/kern/kern_descrip.c ============================================================================== --- head/sys/kern/kern_descrip.c Thu Jun 20 22:21:42 2019 (r349247) +++ head/sys/kern/kern_descrip.c Thu Jun 20 23:07:20 2019 (r349248) @@ -780,7 +780,9 @@ kern_fcntl(struct thread *td, int fd, int cmd, intptr_ } if (arg >= 0) { bsize = fp->f_vnode->v_mount->mnt_stat.f_iosize; - fp->f_seqcount = (arg + bsize - 1) / bsize; + arg = MIN(arg, INT_MAX - bsize + 1); + fp->f_seqcount = MIN(IO_SEQMAX, + (arg + bsize - 1) / bsize); atomic_set_int(&fp->f_flag, FRDAHEAD); } else { atomic_clear_int(&fp->f_flag, FRDAHEAD); Modified: head/sys/kern/sys_pipe.c ============================================================================== --- head/sys/kern/sys_pipe.c Thu Jun 20 22:21:42 2019 (r349247) +++ head/sys/kern/sys_pipe.c Thu Jun 20 23:07:20 2019 (r349248) @@ -1414,7 +1414,7 @@ pipe_poll(struct file *fp, int events, struct ucred *a levents = events & (POLLIN | POLLINIGNEOF | POLLPRI | POLLRDNORM | POLLRDBAND); if (rpipe->pipe_state & PIPE_NAMED && fp->f_flag & FREAD && levents && - fp->f_seqcount == rpipe->pipe_wgen) + fp->f_pipegen == rpipe->pipe_wgen) events |= POLLINIGNEOF; if ((events & POLLINIGNEOF) == 0) { Modified: head/sys/kern/vfs_vnops.c ============================================================================== --- head/sys/kern/vfs_vnops.c Thu Jun 20 22:21:42 2019 (r349247) +++ head/sys/kern/vfs_vnops.c Thu Jun 20 23:07:20 2019 (r349248) @@ -499,7 +499,8 @@ sequential_heuristic(struct uio *uio, struct file *fp) * closely related to the best I/O size for real disks than * to any block size used by software. */ - fp->f_seqcount += howmany(uio->uio_resid, 16384); + fp->f_seqcount += MIN(IO_SEQMAX, + howmany(uio->uio_resid, 16384)); if (fp->f_seqcount > IO_SEQMAX) fp->f_seqcount = IO_SEQMAX; return (fp->f_seqcount << IO_SEQSHIFT); Modified: head/sys/sys/file.h ============================================================================== --- head/sys/sys/file.h Thu Jun 20 22:21:42 2019 (r349247) +++ head/sys/sys/file.h Thu Jun 20 23:07:20 2019 (r349248) @@ -179,7 +179,10 @@ struct file { /* * DTYPE_VNODE specific fields. */ - int f_seqcount; /* (a) Count of sequential accesses. */ + union { + int16_t f_seqcount; /* (a) Count of sequential accesses. */ + int f_pipegen; + }; off_t f_nextoff; /* next expected read/write offset. */ union { struct cdev_privdata *fvn_cdevpriv;