NTFS: Fix a bug in fs/ntfs/runlist.c::ntfs_mapping_pairs_decompress() in
the creation of the unmapped runlist element for the base attribute
extent.
Signed-off-by: Anton Altaparmakov <aia21@cantab.net>
diff --git a/fs/ntfs/ChangeLog b/fs/ntfs/ChangeLog
index 3f78fff..b40c334 100644
--- a/fs/ntfs/ChangeLog
+++ b/fs/ntfs/ChangeLog
@@ -60,6 +60,9 @@
enable bit which is set appropriately and a per inode sparse disable
bit which is preset on some system file inodes as appropriate.
- Enforce that sparse support is disabled on NTFS volumes pre 3.0.
+ - Fix a bug in fs/ntfs/runlist.c::ntfs_mapping_pairs_decompress() in
+ the creation of the unmapped runlist element for the base attribute
+ extent.
2.1.22 - Many bug and race fixes and error handling improvements.
diff --git a/fs/ntfs/runlist.c b/fs/ntfs/runlist.c
index 8438fb1..5244687 100644
--- a/fs/ntfs/runlist.c
+++ b/fs/ntfs/runlist.c
@@ -1,7 +1,7 @@
/**
* runlist.c - NTFS runlist handling code. Part of the Linux-NTFS project.
*
- * Copyright (c) 2001-2004 Anton Altaparmakov
+ * Copyright (c) 2001-2005 Anton Altaparmakov
* Copyright (c) 2002 Richard Russon
*
* This program/include file is free software; you can redistribute it and/or
@@ -59,7 +59,7 @@
*
* As the runlists grow, more memory will be required. To prevent the
* kernel having to allocate and reallocate large numbers of small bits of
- * memory, this function returns and entire page of memory.
+ * memory, this function returns an entire page of memory.
*
* It is up to the caller to serialize access to the runlist @rl.
*
@@ -855,30 +855,42 @@
if (!attr->data.non_resident.lowest_vcn) {
VCN max_cluster;
- max_cluster = (sle64_to_cpu(
+ max_cluster = ((sle64_to_cpu(
attr->data.non_resident.allocated_size) +
vol->cluster_size - 1) >>
- vol->cluster_size_bits;
+ vol->cluster_size_bits) - 1;
/*
- * If there is a difference between the highest_vcn and the
- * highest cluster, the runlist is either corrupt or, more
- * likely, there are more extents following this one.
+ * A highest_vcn of zero means this is a single extent
+ * attribute so simply terminate the runlist with LCN_ENOENT).
*/
- if (deltaxcn < --max_cluster) {
- ntfs_debug("More extents to follow; deltaxcn = 0x%llx, "
- "max_cluster = 0x%llx",
- (unsigned long long)deltaxcn,
- (unsigned long long)max_cluster);
- rl[rlpos].vcn = vcn;
- vcn += rl[rlpos].length = max_cluster - deltaxcn;
- rl[rlpos].lcn = LCN_RL_NOT_MAPPED;
- rlpos++;
- } else if (unlikely(deltaxcn > max_cluster)) {
- ntfs_error(vol->sb, "Corrupt attribute. deltaxcn = "
- "0x%llx, max_cluster = 0x%llx",
- (unsigned long long)deltaxcn,
- (unsigned long long)max_cluster);
- goto mpa_err;
+ if (deltaxcn) {
+ /*
+ * If there is a difference between the highest_vcn and
+ * the highest cluster, the runlist is either corrupt
+ * or, more likely, there are more extents following
+ * this one.
+ */
+ if (deltaxcn < max_cluster) {
+ ntfs_debug("More extents to follow; deltaxcn "
+ "= 0x%llx, max_cluster = "
+ "0x%llx",
+ (unsigned long long)deltaxcn,
+ (unsigned long long)
+ max_cluster);
+ rl[rlpos].vcn = vcn;
+ vcn += rl[rlpos].length = max_cluster -
+ deltaxcn;
+ rl[rlpos].lcn = LCN_RL_NOT_MAPPED;
+ rlpos++;
+ } else if (unlikely(deltaxcn > max_cluster)) {
+ ntfs_error(vol->sb, "Corrupt attribute. "
+ "deltaxcn = 0x%llx, "
+ "max_cluster = 0x%llx",
+ (unsigned long long)deltaxcn,
+ (unsigned long long)
+ max_cluster);
+ goto mpa_err;
+ }
}
rl[rlpos].lcn = LCN_ENOENT;
} else /* Not the base extent. There may be more extents to follow. */