ports/149674: [patch] fusefs-kmod: ftruncate() sycall on FUSE filesystems cause panic

[Dmitrij Tejblum]

>Number:         149674
>Category:       ports
>Synopsis:       [patch] fusefs-kmod: ftruncate() sycall on FUSE filesystems cause panic
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-ports-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Sun Aug 15 14:00:04 UTC 2010
>Closed-Date:
>Last-Modified:
>Originator:     Dmitrij Tejblum
>Release:        8.1-STABLE
>Organization:
>Environment:
>Description:
At early days of FreeBSD 8.x a field named `fo_truncate' was added `struct fileops' in sys/file.h, and ftruncate() syscall was made to use it. FUSE module has its own instance of `struct fileops', but it was not adapted to this change. 
(It seems that FreeBSD 7.x and earlier aren't affected by this bug.)
>How-To-Repeat:
On a FUSE filesystem (e.g. ntfs-3g) do
dd if=/dev/zero count=1 oseek=1000000 of=SOMEFILE
The system will panic.
>Fix:
The attached patch can be added to the files/ directory of the sysutils/fusefs-kmod port as patch-fuse_module__fuse_main.c

Patch attached with submission follows:

--- fuse_module/fuse_main.c.00	2010-08-15 14:40:29.000000000 +0400
+++ fuse_module/fuse_main.c	2010-08-15 15:56:56.000000000 +0400
@@ -108,6 +108,9 @@
 	switch (what) {
 	case MOD_LOAD:                /* kldload */
 
+#if __FreeBSD_version > 800009
+	        fuse_fileops.fo_truncate = vnops.fo_truncate;
+#endif
 		fuse_fileops.fo_ioctl    = vnops.fo_ioctl;
 		fuse_fileops.fo_poll     = vnops.fo_poll;
 		fuse_fileops.fo_kqfilter = vnops.fo_kqfilter;


>Release-Note:
>Audit-Trail:
>Unformatted: