[src/trunk]: src/sys/ufs/ext2fs adjust ext2fs_loadvnode_content() to do the s...

[jdolecek <jdolecek%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/61e9878adad3
branches:  trunk
changeset: 347321:61e9878adad3
user:      jdolecek <jdolecek%NetBSD.org@localhost>
date:      Sat Aug 20 20:05:28 2016 +0000

description:
adjust ext2fs_loadvnode_content() to do the sanity checking before allocating
memory, and avoid reallocaing memory on vnode reload

diffstat:

 sys/ufs/ext2fs/ext2fs_vfsops.c |  26 +++++++++++---------------
 1 files changed, 11 insertions(+), 15 deletions(-)

diffs (67 lines):

diff -r 59e586a9d7d1 -r 61e9878adad3 sys/ufs/ext2fs/ext2fs_vfsops.c
--- a/sys/ufs/ext2fs/ext2fs_vfsops.c    Sat Aug 20 19:53:43 2016 +0000
+++ b/sys/ufs/ext2fs/ext2fs_vfsops.c    Sat Aug 20 20:05:28 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ext2fs_vfsops.c,v 1.200 2016/08/20 19:47:44 jdolecek Exp $     */
+/*     $NetBSD: ext2fs_vfsops.c,v 1.201 2016/08/20 20:05:28 jdolecek Exp $     */
 
 /*
  * Copyright (c) 1989, 1991, 1993, 1994
@@ -60,7 +60,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: ext2fs_vfsops.c,v 1.200 2016/08/20 19:47:44 jdolecek Exp $");
+__KERNEL_RCSID(0, "$NetBSD: ext2fs_vfsops.c,v 1.201 2016/08/20 20:05:28 jdolecek Exp $");
 
 #if defined(_KERNEL_OPT)
 #include "opt_compat_netbsd.h"
@@ -493,22 +493,19 @@
 }
 
 /*
- *
+ * Sanity check the disk vnode content, and copy it over to inode structure.
  */
 static int
 ext2fs_loadvnode_content(struct m_ext2fs *fs, ino_t ino, struct buf *bp, struct inode *ip)
 {
        struct ext2fs_dinode *din;
-       void *cp;
        int error = 0;
 
-       cp = (char *)bp->b_data + (ino_to_fsbo(fs, ino) * EXT2_DINODE_SIZE(fs));
-       din = kmem_alloc(EXT2_DINODE_SIZE(fs), KM_SLEEP);
-       e2fs_iload((struct ext2fs_dinode *)cp, din, EXT2_DINODE_SIZE(fs));
+       din = (struct ext2fs_dinode *)((char *)bp->b_data + (ino_to_fsbo(fs, ino) * EXT2_DINODE_SIZE(fs)));
 
-       /* sanity checks */
+       /* sanity checks - inode data NOT byteswapped at this point */
        if (EXT2_DINODE_FITS(din, e2di_extra_isize, EXT2_DINODE_SIZE(fs))
-           && (EXT2_DINODE_SIZE(fs) - EXT2_REV0_DINODE_SIZE) < din->e2di_extra_isize)
+           && (EXT2_DINODE_SIZE(fs) - EXT2_REV0_DINODE_SIZE) < fs2h16(din->e2di_extra_isize))
        {
                printf("ext2fs: inode %"PRIu64" bad extra_isize %u",
                        ino, din->e2di_extra_isize);
@@ -516,16 +513,15 @@
                goto bad;
        }
 
-       /* replace old dinode; assumes new dinode size is same as old one */
-       if (ip->i_din.e2fs_din)
-               kmem_free(ip->i_din.e2fs_din, EXT2_DINODE_SIZE(fs));
-       ip->i_din.e2fs_din = din;
+       /* everything allright, proceed with copy */
+       if (ip->i_din.e2fs_din == NULL)
+               ip->i_din.e2fs_din = kmem_alloc(EXT2_DINODE_SIZE(fs), KM_SLEEP);
+
+       e2fs_iload(din, ip->i_din.e2fs_din, EXT2_DINODE_SIZE(fs));
 
        ext2fs_set_inode_guid(ip);
-       return error;
 
     bad:
-       kmem_free(din, EXT2_DINODE_SIZE(fs));
        return error;
 }