Merge tag 'dm-4.11-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm

Pull device mapper fixes from Mike Snitzer:

 - two stable fixes for the verity target's FEC support

 - a stable fix for raid target's raid1 support (when no bitmap is used)

 - a 4.11 cache metadata v2 format fix to properly test blocks are clean

* tag 'dm-4.11-fixes-2' of git://git.kernel.org/pub/scm/linux/kernel/git/device-mapper/linux-dm:
  dm verity fec: fix bufio leaks
  dm raid: fix NULL pointer dereference for raid1 without bitmap
  dm cache metadata: fix metadata2 format's blocks_are_clean_separate_dirty
  dm verity fec: limit error correction recursion

4 files changed, 24 insertions, 8 deletions

diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c
index e4c2c1a1e993..6735c8d6a445 100644
--- a/drivers/md/dm-cache-metadata.c
+++ b/drivers/md/dm-cache-metadata.c
@@ -932,7 +932,7 @@ static int blocks_are_clean_separate_dirty(struct dm_cache_metadata *cmd,
         *result = true;
 
         r = dm_bitset_cursor_begin(&cmd->dirty_info, cmd->dirty_root,
-                                   from_cblock(begin), &cmd->dirty_cursor);
+                                   from_cblock(cmd->cache_blocks), &cmd->dirty_cursor);
         if (r) {
                 DMERR("%s: dm_bitset_cursor_begin for dirty failed", __func__);
                 return r;
@@ -959,14 +959,16 @@ static int blocks_are_clean_separate_dirty(struct dm_cache_metadata *cmd,
                         return 0;
                 }
 
+                begin = to_cblock(from_cblock(begin) + 1);
+                if (begin == end)
+                        break;
+
                 r = dm_bitset_cursor_next(&cmd->dirty_cursor);
                 if (r) {
                         DMERR("%s: dm_bitset_cursor_next for dirty failed", __func__);
                         dm_bitset_cursor_end(&cmd->dirty_cursor);
                         return r;
                 }
-
-                begin = to_cblock(from_cblock(begin) + 1);
         }
 
         dm_bitset_cursor_end(&cmd->dirty_cursor);
diff --git a/drivers/md/dm-raid.c b/drivers/md/dm-raid.c
index f8564d63982f..1e217ba84d09 100644
--- a/drivers/md/dm-raid.c
+++ b/drivers/md/dm-raid.c
@@ -3726,7 +3726,7 @@ static int raid_preresume(struct dm_target *ti)
                 return r;
 
         /* Resize bitmap to adjust to changed region size (aka MD bitmap chunksize) */
-        if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) &&
+        if (test_bit(RT_FLAG_RS_BITMAP_LOADED, &rs->runtime_flags) && mddev->bitmap &&
             mddev->bitmap_info.chunksize != to_bytes(rs->requested_bitmap_chunk_sectors)) {
                 r = bitmap_resize(mddev->bitmap, mddev->dev_sectors,
                                   to_bytes(rs->requested_bitmap_chunk_sectors), 0);
diff --git a/drivers/md/dm-verity-fec.c b/drivers/md/dm-verity-fec.c
index 0f0eb8a3d922..78f36012eaca 100644
--- a/drivers/md/dm-verity-fec.c
+++ b/drivers/md/dm-verity-fec.c
@@ -146,8 +146,6 @@ static int fec_decode_bufs(struct dm_verity *v, struct dm_verity_fec_io *fio,
                 block = fec_buffer_rs_block(v, fio, n, i);
                 res = fec_decode_rs8(v, fio, block, &par[offset], neras);
                 if (res < 0) {
-                        dm_bufio_release(buf);
-
                         r = res;
                         goto error;
                 }
@@ -172,6 +170,8 @@ static int fec_decode_bufs(struct dm_verity *v, struct dm_verity_fec_io *fio,
 done:
         r = corrected;
 error:
+        dm_bufio_release(buf);
+
         if (r < 0 && neras)
                 DMERR_LIMIT("%s: FEC %llu: failed to correct: %d",
                             v->data_dev->name, (unsigned long long)rsb, r);
@@ -269,7 +269,7 @@ static int fec_read_bufs(struct dm_verity *v, struct dm_verity_io *io,
                                           &is_zero) == 0) {
                         /* skip known zero blocks entirely */
                         if (is_zero)
-                                continue;
+                                goto done;
 
                         /*
                          * skip if we have already found the theoretical
@@ -439,6 +439,13 @@ int verity_fec_decode(struct dm_verity *v, struct dm_verity_io *io,
         if (!verity_fec_is_enabled(v))
                 return -EOPNOTSUPP;
 
+        if (fio->level >= DM_VERITY_FEC_MAX_RECURSION) {
+                DMWARN_LIMIT("%s: FEC: recursion too deep", v->data_dev->name);
+                return -EIO;
+        }
+
+        fio->level++;
+
         if (type == DM_VERITY_BLOCK_TYPE_METADATA)
                 block += v->data_blocks;
 
@@ -470,7 +477,7 @@ int verity_fec_decode(struct dm_verity *v, struct dm_verity_io *io,
         if (r < 0) {
                 r = fec_decode_rsb(v, io, fio, rsb, offset, true);
                 if (r < 0)
-                        return r;
+                        goto done;
         }
 
         if (dest)
@@ -480,6 +487,8 @@ int verity_fec_decode(struct dm_verity *v, struct dm_verity_io *io,
                 r = verity_for_bv_block(v, io, iter, fec_bv_copy);
         }
 
+done:
+        fio->level--;
         return r;
 }
 
@@ -520,6 +529,7 @@ void verity_fec_init_io(struct dm_verity_io *io)
         memset(fio->bufs, 0, sizeof(fio->bufs));
         fio->nbufs = 0;
         fio->output = NULL;
+        fio->level = 0;
 }
 
 /*
diff --git a/drivers/md/dm-verity-fec.h b/drivers/md/dm-verity-fec.h
index 7fa0298b995e..bb31ce87a933 100644
--- a/drivers/md/dm-verity-fec.h
+++ b/drivers/md/dm-verity-fec.h
@@ -27,6 +27,9 @@
 #define DM_VERITY_FEC_BUF_MAX \
         (1 << (PAGE_SHIFT - DM_VERITY_FEC_BUF_RS_BITS))
 
+/* maximum recursion level for verity_fec_decode */
+#define DM_VERITY_FEC_MAX_RECURSION     4
+
 #define DM_VERITY_OPT_FEC_DEV           "use_fec_from_device"
 #define DM_VERITY_OPT_FEC_BLOCKS        "fec_blocks"
 #define DM_VERITY_OPT_FEC_START         "fec_start"
@@ -58,6 +61,7 @@ struct dm_verity_fec_io {
         unsigned nbufs;         /* number of buffers allocated */
         u8 *output;             /* buffer for corrected output */
         size_t output_pos;
+        unsigned level;         /* recursion level */
 };
 
 #ifdef CONFIG_DM_VERITY_FEC