NTFS: - Set the ntfs_inode->allocated_size to the real allocated size in the

        mft record for resident attributes (fs/ntfs/inode.c).
      - Small readability cleanup to use "a" instead of "ctx->attr"
        everywhere (fs/ntfs/inode.c).

Signed-off-by: Anton Altaparmakov <aia21@cantab.net>

1 files changed, 170 insertions, 174 deletions

diff --git a/fs/ntfs/inode.c b/fs/ntfs/inode.c
index 372c7fcdc068..cfca17384115 100644
--- a/fs/ntfs/inode.c
+++ b/fs/ntfs/inode.c
@@ -525,6 +525,7 @@ static int ntfs_read_locked_inode(struct inode *vi)
         ntfs_volume *vol = NTFS_SB(vi->i_sb);
         ntfs_inode *ni;
         MFT_RECORD *m;
+        ATTR_RECORD *a;
         STANDARD_INFORMATION *si;
         ntfs_attr_search_ctx *ctx;
         int err = 0;
@@ -633,9 +634,10 @@ static int ntfs_read_locked_inode(struct inode *vi)
                 }
                 goto unm_err_out;
         }
+        a = ctx->attr;
         /* Get the standard information attribute value. */
-        si = (STANDARD_INFORMATION*)((char*)ctx->attr +
-                        le16_to_cpu(ctx->attr->data.resident.value_offset));
+        si = (STANDARD_INFORMATION*)((u8*)a +
+                        le16_to_cpu(a->data.resident.value_offset));
 
         /* Transfer information from the standard information into vi. */
         /*
@@ -674,15 +676,16 @@ static int ntfs_read_locked_inode(struct inode *vi)
                         goto skip_attr_list_load;
                 ntfs_debug("Attribute list found in inode 0x%lx.", vi->i_ino);
                 NInoSetAttrList(ni);
-                if (ctx->attr->flags & ATTR_IS_ENCRYPTED ||
-                                ctx->attr->flags & ATTR_COMPRESSION_MASK ||
-                                ctx->attr->flags & ATTR_IS_SPARSE) {
+                a = ctx->attr;
+                if (a->flags & ATTR_IS_ENCRYPTED ||
+                                a->flags & ATTR_COMPRESSION_MASK ||
+                                a->flags & ATTR_IS_SPARSE) {
                         ntfs_error(vi->i_sb, "Attribute list attribute is "
                                         "compressed/encrypted/sparse.");
                         goto unm_err_out;
                 }
                 /* Now allocate memory for the attribute list. */
-                ni->attr_list_size = (u32)ntfs_attr_size(ctx->attr);
+                ni->attr_list_size = (u32)ntfs_attr_size(a);
                 ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
                 if (!ni->attr_list) {
                         ntfs_error(vi->i_sb, "Not enough memory to allocate "
@@ -690,9 +693,9 @@ static int ntfs_read_locked_inode(struct inode *vi)
                         err = -ENOMEM;
                         goto unm_err_out;
                 }
-                if (ctx->attr->non_resident) {
+                if (a->non_resident) {
                         NInoSetAttrListNonResident(ni);
-                        if (ctx->attr->data.non_resident.lowest_vcn) {
+                        if (a->data.non_resident.lowest_vcn) {
                                 ntfs_error(vi->i_sb, "Attribute list has non "
                                                 "zero lowest_vcn.");
                                 goto unm_err_out;
@@ -702,7 +705,7 @@ static int ntfs_read_locked_inode(struct inode *vi)
                          * exclusive access to the inode at this time.
                          */
                         ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
-                                        ctx->attr, NULL);
+                                        a, NULL);
                         if (IS_ERR(ni->attr_list_rl.rl)) {
                                 err = PTR_ERR(ni->attr_list_rl.rl);
                                 ni->attr_list_rl.rl = NULL;
@@ -713,27 +716,26 @@ static int ntfs_read_locked_inode(struct inode *vi)
                         /* Now load the attribute list. */
                         if ((err = load_attribute_list(vol, &ni->attr_list_rl,
                                         ni->attr_list, ni->attr_list_size,
-                                        sle64_to_cpu(ctx->attr->data.
-                                        non_resident.initialized_size)))) {
+                                        sle64_to_cpu(a->data.non_resident.
+                                        initialized_size)))) {
                                 ntfs_error(vi->i_sb, "Failed to load "
                                                 "attribute list attribute.");
                                 goto unm_err_out;
                         }
-                } else /* if (!ctx.attr->non_resident) */ {
-                        if ((u8*)ctx->attr + le16_to_cpu(
-                                        ctx->attr->data.resident.value_offset) +
-                                        le32_to_cpu(
-                                        ctx->attr->data.resident.value_length) >
+                } else /* if (!a->non_resident) */ {
+                        if ((u8*)a + le16_to_cpu(a->data.resident.value_offset)
+                                        + le32_to_cpu(
+                                        a->data.resident.value_length) >
                                         (u8*)ctx->mrec + vol->mft_record_size) {
                                 ntfs_error(vi->i_sb, "Corrupt attribute list "
                                                 "in inode.");
                                 goto unm_err_out;
                         }
                         /* Now copy the attribute list. */
-                        memcpy(ni->attr_list, (u8*)ctx->attr + le16_to_cpu(
-                                        ctx->attr->data.resident.value_offset),
+                        memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
+                                        a->data.resident.value_offset),
                                         le32_to_cpu(
-                                        ctx->attr->data.resident.value_length));
+                                        a->data.resident.value_length));
                 }
         }
 skip_attr_list_load:
@@ -746,7 +748,7 @@ skip_attr_list_load:
                 struct inode *bvi;
                 ntfs_inode *bni;
                 INDEX_ROOT *ir;
-                char *ir_end, *index_end;
+                u8 *ir_end, *index_end;
 
                 /* It is a directory, find index root attribute. */
                 ntfs_attr_reinit_search_ctx(ctx);
@@ -762,17 +764,16 @@ skip_attr_list_load:
                         }
                         goto unm_err_out;
                 }
+                a = ctx->attr;
                 /* Set up the state. */
-                if (unlikely(ctx->attr->non_resident)) {
+                if (unlikely(a->non_resident)) {
                         ntfs_error(vol->sb, "$INDEX_ROOT attribute is not "
                                         "resident.");
                         goto unm_err_out;
                 }
                 /* Ensure the attribute name is placed before the value. */
-                if (unlikely(ctx->attr->name_length &&
-                                (le16_to_cpu(ctx->attr->name_offset) >=
-                                le16_to_cpu(ctx->attr->data.resident.
-                                value_offset)))) {
+                if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
+                                le16_to_cpu(a->data.resident.value_offset)))) {
                         ntfs_error(vol->sb, "$INDEX_ROOT attribute name is "
                                         "placed after the attribute value.");
                         goto unm_err_out;
@@ -783,28 +784,27 @@ skip_attr_list_load:
                  * encrypted. However index root cannot be both compressed and
                  * encrypted.
                  */
-                if (ctx->attr->flags & ATTR_COMPRESSION_MASK)
+                if (a->flags & ATTR_COMPRESSION_MASK)
                         NInoSetCompressed(ni);
-                if (ctx->attr->flags & ATTR_IS_ENCRYPTED) {
-                        if (ctx->attr->flags & ATTR_COMPRESSION_MASK) {
+                if (a->flags & ATTR_IS_ENCRYPTED) {
+                        if (a->flags & ATTR_COMPRESSION_MASK) {
                                 ntfs_error(vi->i_sb, "Found encrypted and "
                                                 "compressed attribute.");
                                 goto unm_err_out;
                         }
                         NInoSetEncrypted(ni);
                 }
-                if (ctx->attr->flags & ATTR_IS_SPARSE)
+                if (a->flags & ATTR_IS_SPARSE)
                         NInoSetSparse(ni);
-                ir = (INDEX_ROOT*)((char*)ctx->attr + le16_to_cpu(
-                                ctx->attr->data.resident.value_offset));
-                ir_end = (char*)ir + le32_to_cpu(
-                                ctx->attr->data.resident.value_length);
-                if (ir_end > (char*)ctx->mrec + vol->mft_record_size) {
+                ir = (INDEX_ROOT*)((u8*)a +
+                                le16_to_cpu(a->data.resident.value_offset));
+                ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
+                if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
                         ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
                                         "corrupt.");
                         goto unm_err_out;
                 }
-                index_end = (char*)&ir->index +
+                index_end = (u8*)&ir->index +
                                 le32_to_cpu(ir->index.index_length);
                 if (index_end > ir_end) {
                         ntfs_error(vi->i_sb, "Directory index is corrupt.");
@@ -891,7 +891,8 @@ skip_attr_list_load:
                                                 "attribute.");
                         goto unm_err_out;
                 }
-                if (!ctx->attr->non_resident) {
+                a = ctx->attr;
+                if (!a->non_resident) {
                         ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
                                         "is resident.");
                         goto unm_err_out;
@@ -900,42 +901,40 @@ skip_attr_list_load:
                  * Ensure the attribute name is placed before the mapping pairs
                  * array.
                  */
-                if (unlikely(ctx->attr->name_length &&
-                                (le16_to_cpu(ctx->attr->name_offset) >=
-                                le16_to_cpu(ctx->attr->data.non_resident.
-                                mapping_pairs_offset)))) {
+                if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
+                                le16_to_cpu(
+                                a->data.non_resident.mapping_pairs_offset)))) {
                         ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name "
                                         "is placed after the mapping pairs "
                                         "array.");
                         goto unm_err_out;
                 }
-                if (ctx->attr->flags & ATTR_IS_ENCRYPTED) {
+                if (a->flags & ATTR_IS_ENCRYPTED) {
                         ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
                                         "is encrypted.");
                         goto unm_err_out;
                 }
-                if (ctx->attr->flags & ATTR_IS_SPARSE) {
+                if (a->flags & ATTR_IS_SPARSE) {
                         ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
                                         "is sparse.");
                         goto unm_err_out;
                 }
-                if (ctx->attr->flags & ATTR_COMPRESSION_MASK) {
+                if (a->flags & ATTR_COMPRESSION_MASK) {
                         ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
                                         "is compressed.");
                         goto unm_err_out;
                 }
-                if (ctx->attr->data.non_resident.lowest_vcn) {
+                if (a->data.non_resident.lowest_vcn) {
                         ntfs_error(vi->i_sb, "First extent of "
                                         "$INDEX_ALLOCATION attribute has non "
                                         "zero lowest_vcn.");
                         goto unm_err_out;
                 }
-                vi->i_size = sle64_to_cpu(
-                                ctx->attr->data.non_resident.data_size);
+                vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
                 ni->initialized_size = sle64_to_cpu(
-                                ctx->attr->data.non_resident.initialized_size);
+                                a->data.non_resident.initialized_size);
                 ni->allocated_size = sle64_to_cpu(
-                                ctx->attr->data.non_resident.allocated_size);
+                                a->data.non_resident.allocated_size);
                 /*
                  * We are done with the mft record, so we release it. Otherwise
                  * we would deadlock in ntfs_attr_iget().
@@ -1013,10 +1012,11 @@ skip_large_dir_stuff:
                         ntfs_error(vi->i_sb, "$DATA attribute is missing.");
                         goto unm_err_out;
                 }
+                a = ctx->attr;
                 /* Setup the state. */
-                if (ctx->attr->non_resident) {
+                if (a->non_resident) {
                         NInoSetNonResident(ni);
-                        if (ctx->attr->flags & ATTR_COMPRESSION_MASK) {
+                        if (a->flags & ATTR_COMPRESSION_MASK) {
                                 NInoSetCompressed(ni);
                                 if (vol->cluster_size > 4096) {
                                         ntfs_error(vi->i_sb, "Found "
@@ -1026,7 +1026,7 @@ skip_large_dir_stuff:
                                                 vol->cluster_size);
                                         goto unm_err_out;
                                 }
-                                if ((ctx->attr->flags & ATTR_COMPRESSION_MASK)
+                                if ((a->flags & ATTR_COMPRESSION_MASK)
                                                 != ATTR_IS_COMPRESSED) {
                                         ntfs_error(vi->i_sb, "Found "
                                                 "unknown compression method or "
@@ -1034,37 +1034,37 @@ skip_large_dir_stuff:
                                         goto unm_err_out;
                                 }
                                 ni->itype.compressed.block_clusters = 1U <<
-                                                ctx->attr->data.non_resident.
+                                                a->data.non_resident.
                                                 compression_unit;
-                                if (ctx->attr->data.non_resident.
-                                                compression_unit != 4) {
+                                if (a->data.non_resident.compression_unit !=
+                                                4) {
                                         ntfs_error(vi->i_sb, "Found "
                                                 "nonstandard compression unit "
                                                 "(%u instead of 4).  Cannot "
                                                 "handle this.",
-                                                ctx->attr->data.non_resident.
+                                                a->data.non_resident.
                                                 compression_unit);
                                         err = -EOPNOTSUPP;
                                         goto unm_err_out;
                                 }
                                 ni->itype.compressed.block_size = 1U << (
-                                                ctx->attr->data.non_resident.
+                                                a->data.non_resident.
                                                 compression_unit +
                                                 vol->cluster_size_bits);
                                 ni->itype.compressed.block_size_bits = ffs(
                                         ni->itype.compressed.block_size) - 1;
                         }
-                        if (ctx->attr->flags & ATTR_IS_ENCRYPTED) {
-                                if (ctx->attr->flags & ATTR_COMPRESSION_MASK) {
+                        if (a->flags & ATTR_IS_ENCRYPTED) {
+                                if (a->flags & ATTR_COMPRESSION_MASK) {
                                         ntfs_error(vi->i_sb, "Found encrypted "
                                                         "and compressed data.");
                                         goto unm_err_out;
                                 }
                                 NInoSetEncrypted(ni);
                         }
-                        if (ctx->attr->flags & ATTR_IS_SPARSE)
+                        if (a->flags & ATTR_IS_SPARSE)
                                 NInoSetSparse(ni);
-                        if (ctx->attr->data.non_resident.lowest_vcn) {
+                        if (a->data.non_resident.lowest_vcn) {
                                 ntfs_error(vi->i_sb, "First extent of $DATA "
                                                 "attribute has non zero "
                                                 "lowest_vcn.");
@@ -1072,28 +1072,28 @@ skip_large_dir_stuff:
                         }
                         /* Setup all the sizes. */
                         vi->i_size = sle64_to_cpu(
-                                        ctx->attr->data.non_resident.data_size);
+                                        a->data.non_resident.data_size);
                         ni->initialized_size = sle64_to_cpu(
-                                        ctx->attr->data.non_resident.
-                                        initialized_size);
+                                        a->data.non_resident.initialized_size);
                         ni->allocated_size = sle64_to_cpu(
-                                        ctx->attr->data.non_resident.
-                                        allocated_size);
-                        if (NInoCompressed(ni)) {
+                                        a->data.non_resident.allocated_size);
+                        if (NInoCompressed(ni))
                                 ni->itype.compressed.size = sle64_to_cpu(
-                                                ctx->attr->data.non_resident.
+                                                a->data.non_resident.
                                                 compressed_size);
-                        }
                 } else { /* Resident attribute. */
-                        /*
-                         * Make all sizes equal for simplicity in read code
-                         * paths. FIXME: Need to keep this in mind when
-                         * converting to non-resident attribute in write code
-                         * path. (Probably only affects truncate().)
-                         */
-                        vi->i_size = ni->initialized_size = ni->allocated_size =
-                                        le32_to_cpu(
-                                        ctx->attr->data.resident.value_length);
+                        /* Setup all the sizes. */
+                        vi->i_size = ni->initialized_size = le32_to_cpu(
+                                        a->data.resident.value_length);
+                        ni->allocated_size = le32_to_cpu(a->length) -
+                                        le16_to_cpu(
+                                        a->data.resident.value_offset);
+                        if (vi->i_size > ni->allocated_size) {
+                                ntfs_error(vi->i_sb, "Resident data attribute "
+                                                "is corrupt (size exceeds "
+                                                "allocation).");
+                                goto unm_err_out;
+                        }
                 }
 no_data_attr_special_case:
                 /* We are done with the mft record, so we release it. */
@@ -1169,6 +1169,7 @@ static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi)
         ntfs_volume *vol = NTFS_SB(vi->i_sb);
         ntfs_inode *ni, *base_ni;
         MFT_RECORD *m;
+        ATTR_RECORD *a;
         ntfs_attr_search_ctx *ctx;
         int err = 0;
 
@@ -1203,24 +1204,21 @@ static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi)
                 err = -ENOMEM;
                 goto unm_err_out;
         }
-
         /* Find the attribute. */
         err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
                         CASE_SENSITIVE, 0, NULL, 0, ctx);
         if (unlikely(err))
                 goto unm_err_out;
-
-        if (!ctx->attr->non_resident) {
+        a = ctx->attr;
+        if (!a->non_resident) {
                 /* Ensure the attribute name is placed before the value. */
-                if (unlikely(ctx->attr->name_length &&
-                                (le16_to_cpu(ctx->attr->name_offset) >=
-                                le16_to_cpu(ctx->attr->data.resident.
-                                value_offset)))) {
+                if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
+                                le16_to_cpu(a->data.resident.value_offset)))) {
                         ntfs_error(vol->sb, "Attribute name is placed after "
                                         "the attribute value.");
                         goto unm_err_out;
                 }
-                if (NInoMstProtected(ni) || ctx->attr->flags) {
+                if (NInoMstProtected(ni) || a->flags) {
                         ntfs_error(vi->i_sb, "Found mst protected attribute "
                                         "or attribute with non-zero flags but "
                                         "the attribute is resident.  Please "
@@ -1228,27 +1226,30 @@ static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi)
                                         "linux-ntfs-dev@lists.sourceforge.net");
                         goto unm_err_out;
                 }
-                /*
-                 * Resident attribute. Make all sizes equal for simplicity in
-                 * read code paths.
-                 */
-                vi->i_size = ni->initialized_size = ni->allocated_size =
-                        le32_to_cpu(ctx->attr->data.resident.value_length);
+                /* Resident attribute.  Setup all the sizes. */
+                vi->i_size = ni->initialized_size = le32_to_cpu(
+                                a->data.resident.value_length);
+                ni->allocated_size = le32_to_cpu(a->length) -
+                                le16_to_cpu(a->data.resident.value_offset);
+                if (vi->i_size > ni->allocated_size) {
+                        ntfs_error(vi->i_sb, "Resident data attribute is "
+                                        "corrupt (size exceeds allocation).");
+                        goto unm_err_out;
+                }
         } else {
                 NInoSetNonResident(ni);
                 /*
                  * Ensure the attribute name is placed before the mapping pairs
                  * array.
                  */
-                if (unlikely(ctx->attr->name_length &&
-                                (le16_to_cpu(ctx->attr->name_offset) >=
-                                le16_to_cpu(ctx->attr->data.non_resident.
-                                mapping_pairs_offset)))) {
+                if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
+                                le16_to_cpu(
+                                a->data.non_resident.mapping_pairs_offset)))) {
                         ntfs_error(vol->sb, "Attribute name is placed after "
                                         "the mapping pairs array.");
                         goto unm_err_out;
                 }
-                if (ctx->attr->flags & ATTR_COMPRESSION_MASK) {
+                if (a->flags & ATTR_COMPRESSION_MASK) {
                         if (NInoMstProtected(ni)) {
                                 ntfs_error(vi->i_sb, "Found mst protected "
                                                 "attribute but the attribute "
@@ -1277,36 +1278,33 @@ static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi)
                                                 vol->cluster_size);
                                 goto unm_err_out;
                         }
-                        if ((ctx->attr->flags & ATTR_COMPRESSION_MASK)
-                                        != ATTR_IS_COMPRESSED) {
+                        if ((a->flags & ATTR_COMPRESSION_MASK) !=
+                                        ATTR_IS_COMPRESSED) {
                                 ntfs_error(vi->i_sb, "Found unknown "
                                                 "compression method.");
                                 goto unm_err_out;
                         }
                         ni->itype.compressed.block_clusters = 1U <<
-                                        ctx->attr->data.non_resident.
-                                        compression_unit;
-                        if (ctx->attr->data.non_resident.compression_unit !=
-                                        4) {
+                                        a->data.non_resident.compression_unit;
+                        if (a->data.non_resident.compression_unit != 4) {
                                 ntfs_error(vi->i_sb, "Found nonstandard "
                                                 "compression unit (%u instead "
                                                 "of 4).  Cannot handle this.",
-                                                ctx->attr->data.non_resident.
+                                                a->data.non_resident.
                                                 compression_unit);
                                 err = -EOPNOTSUPP;
                                 goto unm_err_out;
                         }
                         ni->itype.compressed.block_size = 1U << (
-                                        ctx->attr->data.non_resident.
-                                        compression_unit +
+                                        a->data.non_resident.compression_unit +
                                         vol->cluster_size_bits);
                         ni->itype.compressed.block_size_bits = ffs(
-                                ni->itype.compressed.block_size) - 1;
+                                        ni->itype.compressed.block_size) - 1;
                 }
-                if (ctx->attr->flags & ATTR_IS_ENCRYPTED) {
-                        if (ctx->attr->flags & ATTR_COMPRESSION_MASK) {
-                                ntfs_error(vi->i_sb, "Found encrypted "
-                                                "and compressed data.");
+                if (a->flags & ATTR_IS_ENCRYPTED) {
+                        if (a->flags & ATTR_COMPRESSION_MASK) {
+                                ntfs_error(vi->i_sb, "Found encrypted and "
+                                                "compressed data.");
                                 goto unm_err_out;
                         }
                         if (NInoMstProtected(ni)) {
@@ -1320,7 +1318,7 @@ static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi)
                         }
                         NInoSetEncrypted(ni);
                 }
-                if (ctx->attr->flags & ATTR_IS_SPARSE) {
+                if (a->flags & ATTR_IS_SPARSE) {
                         if (NInoMstProtected(ni)) {
                                 ntfs_error(vi->i_sb, "Found mst protected "
                                                 "attribute but the attribute "
@@ -1332,23 +1330,20 @@ static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi)
                         }
                         NInoSetSparse(ni);
                 }
-                if (ctx->attr->data.non_resident.lowest_vcn) {
+                if (a->data.non_resident.lowest_vcn) {
                         ntfs_error(vi->i_sb, "First extent of attribute has "
                                         "non-zero lowest_vcn.");
                         goto unm_err_out;
                 }
                 /* Setup all the sizes. */
-                vi->i_size = sle64_to_cpu(
-                                ctx->attr->data.non_resident.data_size);
+                vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
                 ni->initialized_size = sle64_to_cpu(
-                                ctx->attr->data.non_resident.initialized_size);
+                                a->data.non_resident.initialized_size);
                 ni->allocated_size = sle64_to_cpu(
-                                ctx->attr->data.non_resident.allocated_size);
-                if (NInoCompressed(ni)) {
+                                a->data.non_resident.allocated_size);
+                if (NInoCompressed(ni))
                         ni->itype.compressed.size = sle64_to_cpu(
-                                        ctx->attr->data.non_resident.
-                                        compressed_size);
-                }
+                                        a->data.non_resident.compressed_size);
         }
 
         /* Setup the operations for this attribute inode. */
@@ -1437,6 +1432,7 @@ static int ntfs_read_locked_index_inode(struct inode *base_vi, struct inode *vi)
         ntfs_inode *ni, *base_ni, *bni;
         struct inode *bvi;
         MFT_RECORD *m;
+        ATTR_RECORD *a;
         ntfs_attr_search_ctx *ctx;
         INDEX_ROOT *ir;
         u8 *ir_end, *index_end;
@@ -1478,30 +1474,28 @@ static int ntfs_read_locked_index_inode(struct inode *base_vi, struct inode *vi)
                                         "missing.");
                 goto unm_err_out;
         }
+        a = ctx->attr;
         /* Set up the state. */
-        if (unlikely(ctx->attr->non_resident)) {
+        if (unlikely(a->non_resident)) {
                 ntfs_error(vol->sb, "$INDEX_ROOT attribute is not resident.");
                 goto unm_err_out;
         }
         /* Ensure the attribute name is placed before the value. */
-        if (unlikely(ctx->attr->name_length &&
-                        (le16_to_cpu(ctx->attr->name_offset) >=
-                        le16_to_cpu(ctx->attr->data.resident.
-                        value_offset)))) {
+        if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
+                        le16_to_cpu(a->data.resident.value_offset)))) {
                 ntfs_error(vol->sb, "$INDEX_ROOT attribute name is placed "
                                 "after the attribute value.");
                 goto unm_err_out;
         }
         /* Compressed/encrypted/sparse index root is not allowed. */
-        if (ctx->attr->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_ENCRYPTED |
+        if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_ENCRYPTED |
                         ATTR_IS_SPARSE)) {
                 ntfs_error(vi->i_sb, "Found compressed/encrypted/sparse index "
                                 "root attribute.");
                 goto unm_err_out;
         }
-        ir = (INDEX_ROOT*)((u8*)ctx->attr +
-                        le16_to_cpu(ctx->attr->data.resident.value_offset));
-        ir_end = (u8*)ir + le32_to_cpu(ctx->attr->data.resident.value_length);
+        ir = (INDEX_ROOT*)((u8*)a + le16_to_cpu(a->data.resident.value_offset));
+        ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
         if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
                 ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is corrupt.");
                 goto unm_err_out;
@@ -1574,7 +1568,7 @@ static int ntfs_read_locked_index_inode(struct inode *base_vi, struct inode *vi)
                                         "$INDEX_ALLOCATION attribute.");
                 goto unm_err_out;
         }
-        if (!ctx->attr->non_resident) {
+        if (!a->non_resident) {
                 ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
                                 "resident.");
                 goto unm_err_out;
@@ -1582,37 +1576,36 @@ static int ntfs_read_locked_index_inode(struct inode *base_vi, struct inode *vi)
         /*
          * Ensure the attribute name is placed before the mapping pairs array.
          */
-        if (unlikely(ctx->attr->name_length && (le16_to_cpu(
-                        ctx->attr->name_offset) >= le16_to_cpu(
-                        ctx->attr->data.non_resident.mapping_pairs_offset)))) {
+        if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
+                        le16_to_cpu(
+                        a->data.non_resident.mapping_pairs_offset)))) {
                 ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name is "
                                 "placed after the mapping pairs array.");
                 goto unm_err_out;
         }
-        if (ctx->attr->flags & ATTR_IS_ENCRYPTED) {
+        if (a->flags & ATTR_IS_ENCRYPTED) {
                 ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
                                 "encrypted.");
                 goto unm_err_out;
         }
-        if (ctx->attr->flags & ATTR_IS_SPARSE) {
+        if (a->flags & ATTR_IS_SPARSE) {
                 ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is sparse.");
                 goto unm_err_out;
         }
-        if (ctx->attr->flags & ATTR_COMPRESSION_MASK) {
+        if (a->flags & ATTR_COMPRESSION_MASK) {
                 ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
                                 "compressed.");
                 goto unm_err_out;
         }
-        if (ctx->attr->data.non_resident.lowest_vcn) {
+        if (a->data.non_resident.lowest_vcn) {
                 ntfs_error(vi->i_sb, "First extent of $INDEX_ALLOCATION "
                                 "attribute has non zero lowest_vcn.");
                 goto unm_err_out;
         }
-        vi->i_size = sle64_to_cpu(ctx->attr->data.non_resident.data_size);
+        vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
         ni->initialized_size = sle64_to_cpu(
-                        ctx->attr->data.non_resident.initialized_size);
-        ni->allocated_size = sle64_to_cpu(
-                        ctx->attr->data.non_resident.allocated_size);
+                        a->data.non_resident.initialized_size);
+        ni->allocated_size = sle64_to_cpu(a->data.non_resident.allocated_size);
         /*
          * We are done with the mft record, so we release it.  Otherwise
          * we would deadlock in ntfs_attr_iget().
@@ -1716,7 +1709,7 @@ int ntfs_read_inode_mount(struct inode *vi)
         struct buffer_head *bh;
         ntfs_inode *ni;
         MFT_RECORD *m = NULL;
-        ATTR_RECORD *attr;
+        ATTR_RECORD *a;
         ntfs_attr_search_ctx *ctx;
         unsigned int i, nr_blocks;
         int err;
@@ -1813,9 +1806,10 @@ int ntfs_read_inode_mount(struct inode *vi)
 
                 ntfs_debug("Attribute list attribute found in $MFT.");
                 NInoSetAttrList(ni);
-                if (ctx->attr->flags & ATTR_IS_ENCRYPTED ||
-                                ctx->attr->flags & ATTR_COMPRESSION_MASK ||
-                                ctx->attr->flags & ATTR_IS_SPARSE) {
+                a = ctx->attr;
+                if (a->flags & ATTR_IS_ENCRYPTED ||
+                                a->flags & ATTR_COMPRESSION_MASK ||
+                                a->flags & ATTR_IS_SPARSE) {
                         ntfs_error(sb, "Attribute list attribute is "
                                         "compressed/encrypted/sparse. Not "
                                         "allowed. $MFT is corrupt. You should "
@@ -1823,16 +1817,16 @@ int ntfs_read_inode_mount(struct inode *vi)
                         goto put_err_out;
                 }
                 /* Now allocate memory for the attribute list. */
-                ni->attr_list_size = (u32)ntfs_attr_size(ctx->attr);
+                ni->attr_list_size = (u32)ntfs_attr_size(a);
                 ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
                 if (!ni->attr_list) {
                         ntfs_error(sb, "Not enough memory to allocate buffer "
                                         "for attribute list.");
                         goto put_err_out;
                 }
-                if (ctx->attr->non_resident) {
+                if (a->non_resident) {
                         NInoSetAttrListNonResident(ni);
-                        if (ctx->attr->data.non_resident.lowest_vcn) {
+                        if (a->data.non_resident.lowest_vcn) {
                                 ntfs_error(sb, "Attribute list has non zero "
                                                 "lowest_vcn. $MFT is corrupt. "
                                                 "You should run chkdsk.");
@@ -1840,7 +1834,7 @@ int ntfs_read_inode_mount(struct inode *vi)
                         }
                         /* Setup the runlist. */
                         ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
-                                        ctx->attr, NULL);
+                                        a, NULL);
                         if (IS_ERR(ni->attr_list_rl.rl)) {
                                 err = PTR_ERR(ni->attr_list_rl.rl);
                                 ni->attr_list_rl.rl = NULL;
@@ -1852,7 +1846,7 @@ int ntfs_read_inode_mount(struct inode *vi)
                         /* Now load the attribute list. */
                         if ((err = load_attribute_list(vol, &ni->attr_list_rl,
                                         ni->attr_list, ni->attr_list_size,
-                                        sle64_to_cpu(ctx->attr->data.
+                                        sle64_to_cpu(a->data.
                                         non_resident.initialized_size)))) {
                                 ntfs_error(sb, "Failed to load attribute list "
                                                 "attribute with error code %i.",
@@ -1860,20 +1854,20 @@ int ntfs_read_inode_mount(struct inode *vi)
                                 goto put_err_out;
                         }
                 } else /* if (!ctx.attr->non_resident) */ {
-                        if ((u8*)ctx->attr + le16_to_cpu(
-                                        ctx->attr->data.resident.value_offset) +
+                        if ((u8*)a + le16_to_cpu(
+                                        a->data.resident.value_offset) +
                                         le32_to_cpu(
-                                        ctx->attr->data.resident.value_length) >
+                                        a->data.resident.value_length) >
                                         (u8*)ctx->mrec + vol->mft_record_size) {
                                 ntfs_error(sb, "Corrupt attribute list "
                                                 "attribute.");
                                 goto put_err_out;
                         }
                         /* Now copy the attribute list. */
-                        memcpy(ni->attr_list, (u8*)ctx->attr + le16_to_cpu(
-                                        ctx->attr->data.resident.value_offset),
+                        memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
+                                        a->data.resident.value_offset),
                                         le32_to_cpu(
-                                        ctx->attr->data.resident.value_length));
+                                        a->data.resident.value_length));
                 }
                 /* The attribute list is now setup in memory. */
                 /*
@@ -1939,25 +1933,25 @@ int ntfs_read_inode_mount(struct inode *vi)
         ntfs_attr_reinit_search_ctx(ctx);
 
         /* Now load all attribute extents. */
-        attr = NULL;
+        a = NULL;
         next_vcn = last_vcn = highest_vcn = 0;
         while (!(err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, next_vcn, NULL, 0,
                         ctx))) {
                 runlist_element *nrl;
 
                 /* Cache the current attribute. */
-                attr = ctx->attr;
+                a = ctx->attr;
                 /* $MFT must be non-resident. */
-                if (!attr->non_resident) {
+                if (!a->non_resident) {
                         ntfs_error(sb, "$MFT must be non-resident but a "
                                         "resident extent was found. $MFT is "
                                         "corrupt. Run chkdsk.");
                         goto put_err_out;
                 }
                 /* $MFT must be uncompressed and unencrypted. */
-                if (attr->flags & ATTR_COMPRESSION_MASK ||
-                                attr->flags & ATTR_IS_ENCRYPTED ||
-                                attr->flags & ATTR_IS_SPARSE) {
+                if (a->flags & ATTR_COMPRESSION_MASK ||
+                                a->flags & ATTR_IS_ENCRYPTED ||
+                                a->flags & ATTR_IS_SPARSE) {
                         ntfs_error(sb, "$MFT must be uncompressed, "
                                         "non-sparse, and unencrypted but a "
                                         "compressed/sparse/encrypted extent "
@@ -1971,7 +1965,7 @@ int ntfs_read_inode_mount(struct inode *vi)
                  * as we have exclusive access to the inode at this time and we
                  * are a mount in progress task, too.
                  */
-                nrl = ntfs_mapping_pairs_decompress(vol, attr, ni->runlist.rl);
+                nrl = ntfs_mapping_pairs_decompress(vol, a, ni->runlist.rl);
                 if (IS_ERR(nrl)) {
                         ntfs_error(sb, "ntfs_mapping_pairs_decompress() "
                                         "failed with error code %ld.  $MFT is "
@@ -1982,7 +1976,7 @@ int ntfs_read_inode_mount(struct inode *vi)
 
                 /* Are we in the first extent? */
                 if (!next_vcn) {
-                        if (attr->data.non_resident.lowest_vcn) {
+                        if (a->data.non_resident.lowest_vcn) {
                                 ntfs_error(sb, "First extent of $DATA "
                                                 "attribute has non zero "
                                                 "lowest_vcn. $MFT is corrupt. "
@@ -1991,15 +1985,15 @@ int ntfs_read_inode_mount(struct inode *vi)
                         }
                         /* Get the last vcn in the $DATA attribute. */
                         last_vcn = sle64_to_cpu(
-                                        attr->data.non_resident.allocated_size)
+                                        a->data.non_resident.allocated_size)
                                         >> vol->cluster_size_bits;
                         /* Fill in the inode size. */
                         vi->i_size = sle64_to_cpu(
-                                        attr->data.non_resident.data_size);
-                        ni->initialized_size = sle64_to_cpu(attr->data.
-                                        non_resident.initialized_size);
+                                        a->data.non_resident.data_size);
+                        ni->initialized_size = sle64_to_cpu(
+                                        a->data.non_resident.initialized_size);
                         ni->allocated_size = sle64_to_cpu(
-                                        attr->data.non_resident.allocated_size);
+                                        a->data.non_resident.allocated_size);
                         /*
                          * Verify the number of mft records does not exceed
                          * 2^32 - 1.
@@ -2056,7 +2050,7 @@ int ntfs_read_inode_mount(struct inode *vi)
                 }
 
                 /* Get the lowest vcn for the next extent. */
-                highest_vcn = sle64_to_cpu(attr->data.non_resident.highest_vcn);
+                highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
                 next_vcn = highest_vcn + 1;
 
                 /* Only one extent or error, which we catch below. */
@@ -2065,7 +2059,7 @@ int ntfs_read_inode_mount(struct inode *vi)
 
                 /* Avoid endless loops due to corruption. */
                 if (next_vcn < sle64_to_cpu(
-                                attr->data.non_resident.lowest_vcn)) {
+                                a->data.non_resident.lowest_vcn)) {
                         ntfs_error(sb, "$MFT has corrupt attribute list "
                                         "attribute. Run chkdsk.");
                         goto put_err_out;
@@ -2076,7 +2070,7 @@ int ntfs_read_inode_mount(struct inode *vi)
                                 "$MFT is corrupt. Run chkdsk.");
                 goto put_err_out;
         }
-        if (!attr) {
+        if (!a) {
                 ntfs_error(sb, "$MFT/$DATA attribute not found. $MFT is "
                                 "corrupt. Run chkdsk.");
                 goto put_err_out;
@@ -2318,6 +2312,7 @@ int ntfs_truncate(struct inode *vi)
         ntfs_volume *vol = ni->vol;
         ntfs_attr_search_ctx *ctx;
         MFT_RECORD *m;
+        ATTR_RECORD *a;
         const char *te = "  Leaving file length out of sync with i_size.";
         int err;
 
@@ -2354,14 +2349,15 @@ int ntfs_truncate(struct inode *vi)
                                         vi->i_ino, err);
                 goto err_out;
         }
+        a = ctx->attr;
         /* If the size has not changed there is nothing to do. */
-        if (ntfs_attr_size(ctx->attr) == i_size_read(vi))
+        if (ntfs_attr_size(a) == i_size_read(vi))
                 goto done;
         // TODO: Implement the truncate...
         ntfs_error(vi->i_sb, "Inode size has changed but this is not "
                         "implemented yet.  Resetting inode size to old value. "
                         " This is most likely a bug in the ntfs driver!");
-        i_size_write(vi, ntfs_attr_size(ctx->attr)); 
+        i_size_write(vi, ntfs_attr_size(a)); 
 done:
         ntfs_attr_put_search_ctx(ctx);
         unmap_mft_record(ni);