Re: kern/47226: KASSERT while running t_faccessat on tmpfs mount

["J. Hannken-Illjes" <hannken%eis.cs.tu-bs.de@localhost>]

The following reply was made to PR kern/47226; it has been noted by GNATS.

From: "J. Hannken-Illjes" <hannken%eis.cs.tu-bs.de@localhost>
To: gnats-bugs%NetBSD.org@localhost
Cc: 
Subject: Re: kern/47226: KASSERT while running t_faccessat on tmpfs mount
Date: Wed, 21 Nov 2012 19:39:27 +0100

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 Both fd_nameiat() and fd_nameiat_simple() call VOP_ACCESS() on
 an unlocked vnode which is wrong.
 
 The untested diff attached could fix it.
 
 --
 J. Hannken-Illjes - hannken%eis.cs.tu-bs.de@localhost - TU Braunschweig 
(Germany)
 
 
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 Index: vfs_syscalls.c
 ===================================================================
 RCS file: /cvsroot/src/sys/kern/vfs_syscalls.c,v
 retrieving revision 1.461
 diff -p -u -2 -r1.461 vfs_syscalls.c
 --- vfs_syscalls.c     19 Nov 2012 15:01:17 -0000      1.461
 +++ vfs_syscalls.c     21 Nov 2012 18:40:17 -0000
 @@ -183,5 +183,7 @@ fd_nameiat(struct lwp *l, int fdat, stru
  
                if (!(dfp->f_flag & FSEARCH)) {
 +                      vn_lock(dfp->f_data, LK_EXCLUSIVE);
                        error = VOP_ACCESS(dfp->f_data, VEXEC, l->l_cred);
 +                      VOP_UNLOCK(dfp->f_data);
                        if (error)
                                goto cleanup;
 @@ -213,5 +215,7 @@ fd_nameiat_simple_user(struct lwp *l, in
  
                if (!(dfp->f_flag & FSEARCH)) {
 +                      vn_lock(dfp->f_data, LK_EXCLUSIVE);
                        error = VOP_ACCESS(dfp->f_data, VEXEC, l->l_cred);
 +                      VOP_UNLOCK(dfp->f_data);
                        if (error)
                                goto cleanup;
 
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