From: Danila Chernetsov <listdansp@xxxxxxx>
[ Upstream commit aa4b92c5234878d55da96d387ea4d3695ca5e4ab ]
In ntfs_mft_data_extend_allocation_nolock(), if an error condition occurs
prior to 'ctx' being set to a non-NULL value, avoid dereferencing the NULL
'ctx' pointer in error handling.
Found by Linux Verification Center (linuxtesting.org) with SVACE.
Signed-off-by: Danila Chernetsov <listdansp@xxxxxxx>
Reviewed-by: Namjae Jeon <linkinjeon@xxxxxxxxxx>
Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/ntfs/mft.c | 36 +++++++++++++++++++-----------------
1 file changed, 19 insertions(+), 17 deletions(-)
diff --git a/fs/ntfs/mft.c b/fs/ntfs/mft.c
index 48030899dc6ec..0155f106ec344 100644
--- a/fs/ntfs/mft.c
+++ b/fs/ntfs/mft.c
@@ -1955,36 +1955,38 @@ static int ntfs_mft_data_extend_allocation_nolock(ntfs_volume *vol)
"attribute.%s", es);
NVolSetErrors(vol);
}
- a = ctx->attr;
+
if (ntfs_rl_truncate_nolock(vol, &mft_ni->runlist, old_last_vcn)) {
ntfs_error(vol->sb, "Failed to truncate mft data attribute "
"runlist.%s", es);
NVolSetErrors(vol);
}
- if (mp_rebuilt && !IS_ERR(ctx->mrec)) {
- if (ntfs_mapping_pairs_build(vol, (u8*)a + le16_to_cpu(
+ if (ctx) {
+ a = ctx->attr;
+ if (mp_rebuilt && !IS_ERR(ctx->mrec)) {
+ if (ntfs_mapping_pairs_build(vol, (u8 *)a + le16_to_cpu(
a->data.non_resident.mapping_pairs_offset),
old_alen - le16_to_cpu(
- a->data.non_resident.mapping_pairs_offset),
+ a->data.non_resident.mapping_pairs_offset),
rl2, ll, -1, NULL)) {
- ntfs_error(vol->sb, "Failed to restore mapping pairs "
+ ntfs_error(vol->sb, "Failed to restore mapping pairs "
"array.%s", es);
- NVolSetErrors(vol);
- }
- if (ntfs_attr_record_resize(ctx->mrec, a, old_alen)) {
- ntfs_error(vol->sb, "Failed to restore attribute "
+ NVolSetErrors(vol);
+ }
+ if (ntfs_attr_record_resize(ctx->mrec, a, old_alen)) {
+ ntfs_error(vol->sb, "Failed to restore attribute "
"record.%s", es);
+ NVolSetErrors(vol);
+ }
+ flush_dcache_mft_record_page(ctx->ntfs_ino);
+ mark_mft_record_dirty(ctx->ntfs_ino);
+ } else if (IS_ERR(ctx->mrec)) {
+ ntfs_error(vol->sb, "Failed to restore attribute search "
+ "context.%s", es);
NVolSetErrors(vol);
}
- flush_dcache_mft_record_page(ctx->ntfs_ino);
- mark_mft_record_dirty(ctx->ntfs_ino);
- } else if (IS_ERR(ctx->mrec)) {
- ntfs_error(vol->sb, "Failed to restore attribute search "
- "context.%s", es);
- NVolSetErrors(vol);
- }
- if (ctx)
ntfs_attr_put_search_ctx(ctx);
+ }
if (!IS_ERR(mrec))
unmap_mft_record(mft_ni);
up_write(&mft_ni->runlist.lock);
--
2.39.2
