xfs
[Top] [All Lists]

[patch 06/11] Fix xfs_bulkstat_one size checks & error handling

To: xfs@xxxxxxxxxxx
Subject: [patch 06/11] Fix xfs_bulkstat_one size checks & error handling
From: sandeen@xxxxxxxxxxx
Date: Tue, 18 Nov 2008 22:44:07 -0600
Cc: hch@xxxxxxxxxxxxx, david@xxxxxxxxxxxxx
References: <20081119044401.573365619@xxxxxxxxxxx>
User-agent: quilt/0.46-1
The 32-bit xfs_blkstat_one handler was failing because
a size check checked whether the remaining (32-bit)
user buffer was less than the (64-bit) bulkstat buffer,
and failed with ENOMEM if so.  Move this check
into the respective handlers so that they check the
correct sizes.

Also, the formatters were returning negative errors
or positive bytes copied; this was odd in the positive
error value world of xfs, and handled wrong by at least
some of the callers, which treated the bytes returned
as an error value.  Move the bytes-used assignment
into the formatters.

Signed-off-by: Eric Sandeen <sandeen@xxxxxxxxxxx>
--

Index: linux-2.6-xfs/fs/xfs/linux-2.6/xfs_ioctl32.c
===================================================================
--- linux-2.6-xfs.orig/fs/xfs/linux-2.6/xfs_ioctl32.c
+++ linux-2.6-xfs/fs/xfs/linux-2.6/xfs_ioctl32.c
@@ -211,13 +211,18 @@ xfs_bstime_store_compat(
        return 0;
 }
 
+/* Return 0 on success or positive error (to xfs_bulkstat()) */
 STATIC int
 xfs_bulkstat_one_fmt_compat(
        void                    __user *ubuffer,
+       int                     ubsize,
+       int                     *ubused,
        const xfs_bstat_t       *buffer)
 {
        compat_xfs_bstat_t __user *p32 = ubuffer;
 
+       if (ubsize < sizeof(*p32))
+               return XFS_ERROR(ENOMEM);
        if (put_user(buffer->bs_ino, &p32->bs_ino) ||
            put_user(buffer->bs_mode, &p32->bs_mode) ||
            put_user(buffer->bs_nlink, &p32->bs_nlink) ||
@@ -238,8 +243,10 @@ xfs_bulkstat_one_fmt_compat(
            put_user(buffer->bs_dmevmask, &p32->bs_dmevmask) ||
            put_user(buffer->bs_dmstate, &p32->bs_dmstate) ||
            put_user(buffer->bs_aextents, &p32->bs_aextents))
-               return -XFS_ERROR(EFAULT);
-       return sizeof(*p32);
+               return XFS_ERROR(EFAULT);
+       if (ubused)
+               *ubused = sizeof(*p32);
+       return 0;
 }
 
 STATIC int
Index: linux-2.6-xfs/fs/xfs/xfs_itable.c
===================================================================
--- linux-2.6-xfs.orig/fs/xfs/xfs_itable.c
+++ linux-2.6-xfs/fs/xfs/xfs_itable.c
@@ -192,14 +192,21 @@ xfs_bulkstat_one_dinode(
        }
 }
 
+/* Return 0 on success or positive error */
 STATIC int
 xfs_bulkstat_one_fmt(
        void                    __user *ubuffer,
+       int                     ubsize,
+       int                     *ubused,
        const xfs_bstat_t       *buffer)
 {
+       if (ubsize < sizeof(*buffer))
+               return XFS_ERROR(ENOMEM);
        if (copy_to_user(ubuffer, buffer, sizeof(*buffer)))
-               return -EFAULT;
-       return sizeof(*buffer);
+               return XFS_ERROR(EFAULT);
+       if (ubused)
+               *ubused = sizeof(*buffer);
+       return 0;
 }
 
 /*
@@ -227,8 +234,6 @@ xfs_bulkstat_one_int(
 
        if (!buffer || xfs_internal_inum(mp, ino))
                return XFS_ERROR(EINVAL);
-       if (ubsize < sizeof(*buf))
-               return XFS_ERROR(ENOMEM);
 
        buf = kmem_alloc(sizeof(*buf), KM_SLEEP);
 
@@ -243,15 +248,11 @@ xfs_bulkstat_one_int(
                xfs_bulkstat_one_dinode(mp, ino, dip, buf);
        }
 
-       error = formatter(buffer, buf);
-       if (error < 0)  {
-               error = EFAULT;
+       error = formatter(buffer, ubsize, ubused, buf);
+       if (error)
                goto out_free;
-       }
 
        *stat = BULKSTAT_RV_DIDONE;
-       if (ubused)
-               *ubused = error;
 
  out_free:
        kmem_free(buf);
Index: linux-2.6-xfs/fs/xfs/xfs_itable.h
===================================================================
--- linux-2.6-xfs.orig/fs/xfs/xfs_itable.h
+++ linux-2.6-xfs/fs/xfs/xfs_itable.h
@@ -71,6 +71,8 @@ xfs_bulkstat_single(
 
 typedef int (*bulkstat_one_fmt_pf)(  /* used size in bytes or negative error */
        void                    __user *ubuffer, /* buffer to write to */
+       int                     ubsize,          /* remaining user buffer sz */
+       int                     *ubused,         /* bytes used by formatter */
        const xfs_bstat_t       *buffer);        /* buffer to read from */
 
 int

-- 

<Prev in Thread] Current Thread [Next in Thread>