diff options
Diffstat (limited to 'fs/ntfs/attrib.c')
| -rw-r--r-- | fs/ntfs/attrib.c | 32 |
1 files changed, 31 insertions, 1 deletions
diff --git a/fs/ntfs/attrib.c b/fs/ntfs/attrib.c index 79dda398068..98b5b96e839 100644 --- a/fs/ntfs/attrib.c +++ b/fs/ntfs/attrib.c @@ -43,6 +43,9 @@ * which is not an error as such. This is -ENOENT. It means that @vcn is out * of bounds of the runlist. * + * Note the runlist can be NULL after this function returns if @vcn is zero and + * the attribute has zero allocated size, i.e. there simply is no runlist. + * * Locking: - The runlist must be locked for writing. * - This function modifies the runlist. */ @@ -54,6 +57,7 @@ int ntfs_map_runlist_nolock(ntfs_inode *ni, VCN vcn) ATTR_RECORD *a; ntfs_attr_search_ctx *ctx; runlist_element *rl; + unsigned long flags; int err = 0; ntfs_debug("Mapping runlist part containing vcn 0x%llx.", @@ -85,8 +89,11 @@ int ntfs_map_runlist_nolock(ntfs_inode *ni, VCN vcn) * ntfs_mapping_pairs_decompress() fails. */ end_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn) + 1; - if (unlikely(!a->data.non_resident.lowest_vcn && end_vcn <= 1)) + if (unlikely(!a->data.non_resident.lowest_vcn && end_vcn <= 1)) { + read_lock_irqsave(&ni->size_lock, flags); end_vcn = ni->allocated_size >> ni->vol->cluster_size_bits; + read_unlock_irqrestore(&ni->size_lock, flags); + } if (unlikely(vcn >= end_vcn)) { err = -ENOENT; goto err_out; @@ -165,6 +172,7 @@ LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn, const BOOL write_locked) { LCN lcn; + unsigned long flags; BOOL is_retry = FALSE; ntfs_debug("Entering for i_ino 0x%lx, vcn 0x%llx, %s_locked.", @@ -173,6 +181,14 @@ LCN ntfs_attr_vcn_to_lcn_nolock(ntfs_inode *ni, const VCN vcn, BUG_ON(!ni); BUG_ON(!NInoNonResident(ni)); BUG_ON(vcn < 0); + if (!ni->runlist.rl) { + read_lock_irqsave(&ni->size_lock, flags); + if (!ni->allocated_size) { + read_unlock_irqrestore(&ni->size_lock, flags); + return LCN_ENOENT; + } + read_unlock_irqrestore(&ni->size_lock, flags); + } retry_remap: /* Convert vcn to lcn. If that fails map the runlist and retry once. */ lcn = ntfs_rl_vcn_to_lcn(ni->runlist.rl, vcn); @@ -255,6 +271,7 @@ retry_remap: runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni, const VCN vcn, const BOOL write_locked) { + unsigned long flags; runlist_element *rl; int err = 0; BOOL is_retry = FALSE; @@ -265,6 +282,14 @@ runlist_element *ntfs_attr_find_vcn_nolock(ntfs_inode *ni, const VCN vcn, BUG_ON(!ni); BUG_ON(!NInoNonResident(ni)); BUG_ON(vcn < 0); + if (!ni->runlist.rl) { + read_lock_irqsave(&ni->size_lock, flags); + if (!ni->allocated_size) { + read_unlock_irqrestore(&ni->size_lock, flags); + return ERR_PTR(-ENOENT); + } + read_unlock_irqrestore(&ni->size_lock, flags); + } retry_remap: rl = ni->runlist.rl; if (likely(rl && vcn >= rl[0].vcn)) { @@ -528,6 +553,11 @@ int load_attribute_list(ntfs_volume *vol, runlist *runlist, u8 *al_start, block_size_bits = sb->s_blocksize_bits; down_read(&runlist->lock); rl = runlist->rl; + if (!rl) { + ntfs_error(sb, "Cannot read attribute list since runlist is " + "missing."); + goto err_out; + } /* Read all clusters specified by the runlist one run at a time. */ while (rl->length) { lcn = ntfs_rl_vcn_to_lcn(rl, rl->vcn); |