xfs: create a separate hashname function for extended attributes

Source kernel commit: a64e0134754bf88021e937aa34f1fbb5b524e585

Create a separate function to compute name hashvalues for extended
attributes.  When we get to parent pointers we'll be altering the rules
so that metadump obfuscation doesn't turn heinous.

Signed-off-by: Darrick J. Wong <djwong@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>

diff --git a/libxfs/xfs_attr.c b/libxfs/xfs_attr.c
index 7f64d8a2ed9e2c4926ad5cddac9f3e755df41dba..91e7961c2fad79c8358ae2c8554a716578379fba 100644 (file)
--- a/libxfs/xfs_attr.c
+++ b/libxfs/xfs_attr.c
@@ -279,7 +279,7 @@ xfs_attr_get(
                args->owner = args->dp->i_ino;
        args->geo = args->dp->i_mount->m_attr_geo;
        args->whichfork = XFS_ATTR_FORK;
-       args->hashval = xfs_da_hashname(args->name, args->namelen);
+       xfs_attr_sethash(args);
 
        /* Entirely possible to look up a name which doesn't exist */
        args->op_flags = XFS_DA_OP_OKNOENT;
@@ -414,6 +414,30 @@ out:
        return error;
 }
 
+/* Compute the hash value for a user/root/secure extended attribute */
+xfs_dahash_t
+xfs_attr_hashname(
+       const uint8_t           *name,
+       int                     namelen)
+{
+       return xfs_da_hashname(name, namelen);
+}
+
+/* Compute the hash value for any extended attribute from any namespace. */
+xfs_dahash_t
+xfs_attr_hashval(
+       struct xfs_mount        *mp,
+       unsigned int            attr_flags,
+       const uint8_t           *name,
+       int                     namelen,
+       const void              *value,
+       int                     valuelen)
+{
+       ASSERT(xfs_attr_check_namespace(attr_flags));
+
+       return xfs_attr_hashname(name, namelen);
+}
+
 /*
  * Handle the state change on completion of a multi-state attr operation.
  *
@@ -924,7 +948,7 @@ xfs_attr_set(
                args->owner = args->dp->i_ino;
        args->geo = mp->m_attr_geo;
        args->whichfork = XFS_ATTR_FORK;
-       args->hashval = xfs_da_hashname(args->name, args->namelen);
+       xfs_attr_sethash(args);
 
        /*
         * We have no control over the attribute names that userspace passes us

diff --git a/libxfs/xfs_attr.h b/libxfs/xfs_attr.h
index cd106b0a424fa145ef7a704637d5cb62dd480647..c63b1d610e53bc0319ea88b6d50749b105cbbbf7 100644 (file)
--- a/libxfs/xfs_attr.h
+++ b/libxfs/xfs_attr.h
@@ -628,6 +628,20 @@ xfs_attr_init_replace_state(struct xfs_da_args *args)
        return xfs_attr_init_add_state(args);
 }
 
+xfs_dahash_t xfs_attr_hashname(const uint8_t *name, int namelen);
+
+xfs_dahash_t xfs_attr_hashval(struct xfs_mount *mp, unsigned int attr_flags,
+               const uint8_t *name, int namelen, const void *value,
+               int valuelen);
+
+/* Set the hash value for any extended attribute from any namespace. */
+static inline void xfs_attr_sethash(struct xfs_da_args *args)
+{
+       args->hashval = xfs_attr_hashval(args->dp->i_mount, args->attr_filter,
+                                        args->name, args->namelen,
+                                        args->value, args->valuelen);
+}
+
 extern struct kmem_cache *xfs_attr_intent_cache;
 int __init xfs_attr_intent_init_cache(void);
 void xfs_attr_intent_destroy_cache(void);

diff --git a/libxfs/xfs_attr_leaf.c b/libxfs/xfs_attr_leaf.c
index c6322fbd2e7f2a2e999d618c34a349d88fe01fde..212347bc3bdb7b9764e99013ece8a3d80a961294 100644 (file)
--- a/libxfs/xfs_attr_leaf.c
+++ b/libxfs/xfs_attr_leaf.c
@@ -945,14 +945,13 @@ xfs_attr_shortform_to_leaf(
                nargs.namelen = sfe->namelen;
                nargs.value = &sfe->nameval[nargs.namelen];
                nargs.valuelen = sfe->valuelen;
-               nargs.hashval = xfs_da_hashname(sfe->nameval,
-                                               sfe->namelen);
                nargs.attr_filter = sfe->flags & XFS_ATTR_NSP_ONDISK_MASK;
                if (!xfs_attr_check_namespace(sfe->flags)) {
                        xfs_da_mark_sick(args);
                        error = -EFSCORRUPTED;
                        goto out;
                }
+               xfs_attr_sethash(&nargs);
                error = xfs_attr3_leaf_lookup_int(bp, &nargs); /* set a->index */
                ASSERT(error == -ENOATTR);
                error = xfs_attr3_leaf_add(bp, &nargs);