Fri Jan 20 22:07:58 2012 UTC ()

Ensure psshfs_node_read() completely reads all data before return.
Fixes file corruption in psshfs exposed with kernel MAXPHYS at 128KiB.


(jakllsch)

diff -r1.63 -r1.64 src/usr.sbin/puffs/mount_psshfs/node.c

--- src/usr.sbin/puffs/mount_psshfs/node.c 2011/08/12 04:14:00	1.63
+++ src/usr.sbin/puffs/mount_psshfs/node.c 2012/01/20 22:07:58	1.64

 @@ -1,14 +1,14 @@
-/*	$NetBSD: node.c,v 1.63 2011/08/12 04:14:00 riastradh Exp $	*/
+/*	$NetBSD: node.c,v 1.64 2012/01/20 22:07:58 jakllsch Exp $	*/
 /*
  * Copyright (c) 2006-2009  Antti Kantee.  All Rights Reserved.
+ *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
+ *
 @@ -17,27 +17,27 @@
  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
 #include <sys/cdefs.h>
 #ifndef lint
-__RCSID("$NetBSD: node.c,v 1.63 2011/08/12 04:14:00 riastradh Exp $");
+__RCSID("$NetBSD: node.c,v 1.64 2012/01/20 22:07:58 jakllsch Exp $");
 #endif /* !lint */
 #include <assert.h>
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include "psshfs.h"
 #include "sftp_proto.h"
 int
 psshfs_node_lookup(struct puffs_usermount *pu, puffs_cookie_t opc,
 	struct puffs_newinfo *pni, const struct puffs_cn *pcn)
 @@ -515,60 +515,70 @@ psshfs_node_read(struct puffs_usermount
+			}
 		psn->stat &= ~PSN_LAZYWAIT_R;
 		if ((rv = psn->lazyopen_err_r) != 0)
 			goto farout;
+	}
 	/* if there is still no handle, just refuse to live with this */
 	if (!psn->fhand_r) {
 		rv = EINVAL;
 		goto farout;
+	}
 again:
 	readlen = *resid;
 	psbuf_req_data(pb, SSH_FXP_READ, reqid, psn->fhand_r, psn->fhand_r_len);
 	psbuf_put_8(pb, offset);
 	psbuf_put_4(pb, readlen);
 	/*
 	 * Do this *after* accessing the file, the handle might not
 	 * exist after blocking.
 	 */
 	if (max_reads && ++psn->readcount > max_reads) {
 		struct psshfs_wait pw;
 		pw.pw_cc = pcc;
 		pw.pw_type = PWTYPE_READ2;
 		TAILQ_INSERT_TAIL(&psn->pw, &pw, pw_entries);
 		puffs_cc_yield(pcc);
+	}
 	GETRESPONSE(pb, pctx->sshfd_data);
 	rv = psbuf_do_data(pb, buf, &readlen);
-	if (rv == 0)
+	if (rv == 0) {
 		*resid -= readlen;
 		buf += readlen;
 		offset += readlen;
+	}
  out:
 	if (max_reads && --psn->readcount >= max_reads) {
 		TAILQ_FOREACH(pwp, &psn->pw, pw_entries)
 			if (pwp->pw_type == PWTYPE_READ2)
 				break;
 		assert(pwp != NULL);
 		puffs_cc_schedule(pwp->pw_cc);
 		TAILQ_REMOVE(&psn->pw, pwp, pw_entries);
+	}
 	if (rv == 0 && *resid > 0) {
 		reqid = NEXTREQ(pctx);
 		psbuf_recycleout(pb);
 		goto again;
+	}
  farout:
 	/* check if we need a lazyclose */
 	if (psn->stat & PSN_HANDLECLOSE && psn->fhand_r) {
 		TAILQ_FOREACH(pwp, &psn->pw, pw_entries)
 			if (pwp->pw_type == PWTYPE_READ1)
 				break;
 		if (pwp == NULL)
 			closehandles(pu, psn, HANDLE_READ);
+	}
 	PSSHFSRETURN(rv);
+}
 /* XXX: we should getattr for size */