X-Git-Url: http://review.tizen.org/git/?a=blobdiff_plain;f=fs%2Ferofs%2Fzmap.c;h=39cc014dba40caec25d571c19a0e2fd28f6290af;hb=9f31d8c889d9a4e47bfcc6c4537d0c9f89fe582c;hp=0bb66927e3d0678343da58bbd4aaa5249c1a4980;hpb=991f173cd23cea2b4102cb78f779a7a43c29e76f;p=platform%2Fkernel%2Flinux-starfive.git

diff --git a/fs/erofs/zmap.c b/fs/erofs/zmap.c
index 0bb6692..39cc014 100644
--- a/fs/erofs/zmap.c
+++ b/fs/erofs/zmap.c
@@ -694,10 +694,15 @@ static int z_erofs_do_map_blocks(struct inode *inode,
 		map->m_pa = blknr_to_addr(m.pblk);
 		err = z_erofs_get_extent_compressedlen(&m, initial_lcn);
 		if (err)
-			goto out;
+			goto unmap_out;
 	}
 
 	if (m.headtype == Z_EROFS_VLE_CLUSTER_TYPE_PLAIN) {
+		if (map->m_llen > map->m_plen) {
+			DBG_BUGON(1);
+			err = -EFSCORRUPTED;
+			goto unmap_out;
+		}
 		if (vi->z_advise & Z_EROFS_ADVISE_INTERLACED_PCLUSTER)
 			map->m_algorithmformat =
 				Z_EROFS_COMPRESSION_INTERLACED;
@@ -718,14 +723,12 @@ static int z_erofs_do_map_blocks(struct inode *inode,
 		if (!err)
 			map->m_flags |= EROFS_MAP_FULL_MAPPED;
 	}
+
 unmap_out:
 	erofs_unmap_metabuf(&m.map->buf);
-
-out:
 	erofs_dbg("%s, m_la %llu m_pa %llu m_llen %llu m_plen %llu m_flags 0%o",
 		  __func__, map->m_la, map->m_pa,
 		  map->m_llen, map->m_plen, map->m_flags);
-
 	return err;
 }
 
@@ -790,12 +793,16 @@ static int z_erofs_iomap_begin_report(struct inode *inode, loff_t offset,
 		iomap->type = IOMAP_HOLE;
 		iomap->addr = IOMAP_NULL_ADDR;
 		/*
-		 * No strict rule how to describe extents for post EOF, yet
-		 * we need do like below. Otherwise, iomap itself will get
+		 * No strict rule on how to describe extents for post EOF, yet
+		 * we need to do like below. Otherwise, iomap itself will get
 		 * into an endless loop on post EOF.
+		 *
+		 * Calculate the effective offset by subtracting extent start
+		 * (map.m_la) from the requested offset, and add it to length.
+		 * (NB: offset >= map.m_la always)
 		 */
 		if (iomap->offset >= inode->i_size)
-			iomap->length = length + map.m_la - offset;
+			iomap->length = length + offset - map.m_la;
 	}
 	iomap->flags = 0;
 	return 0;