Merge v7.1.5linux-rolling-stable

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 204 insertions, 2 deletions

diff --git a/fs/ocfs2/inode.c b/fs/ocfs2/inode.c
index a510a0eb1adc..662dbc845b8b 100644
--- a/fs/ocfs2/inode.c
+++ b/fs/ocfs2/inode.c
@@ -13,6 +13,7 @@
 #include <linux/pagemap.h>
 #include <linux/quotaops.h>
 #include <linux/iversion.h>
+#include <linux/fs_dirent.h>
 
 #include <asm/byteorder.h>
 
@@ -64,7 +65,40 @@ static int ocfs2_filecheck_read_inode_block_full(struct inode *inode,
 static int ocfs2_filecheck_validate_inode_block(struct super_block *sb,
 						struct buffer_head *bh);
 static int ocfs2_filecheck_repair_inode_block(struct super_block *sb,
-					      struct buffer_head *bh);
+						      struct buffer_head *bh);
+
+static bool ocfs2_valid_inode_mode(umode_t mode)
+{
+	return fs_umode_to_ftype(mode) != FT_UNKNOWN;
+}
+
+static bool ocfs2_dinode_has_unexpected_rdev(struct ocfs2_dinode *di)
+{
+	umode_t mode = le16_to_cpu(di->i_mode);
+
+	if (le32_to_cpu(di->i_flags) & OCFS2_SYSTEM_FL)
+		return false;
+
+	return !S_ISCHR(mode) && !S_ISBLK(mode) && di->id1.dev1.i_rdev != 0;
+}
+
+static bool ocfs2_dinode_has_size_without_clusters(struct super_block *sb,
+						   struct ocfs2_dinode *di)
+{
+	umode_t mode = le16_to_cpu(di->i_mode);
+
+	if (le32_to_cpu(di->i_flags) & OCFS2_SYSTEM_FL)
+		return false;
+	if (le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_DATA_FL)
+		return false;
+	if (!le64_to_cpu(di->i_size) || le32_to_cpu(di->i_clusters))
+		return false;
+
+	if (S_ISDIR(mode))
+		return true;
+
+	return !ocfs2_sparse_alloc(OCFS2_SB(sb)) && S_ISREG(mode);
+}
 
 void ocfs2_set_inode_flags(struct inode *inode)
 {
@@ -1494,6 +1528,86 @@ int ocfs2_validate_inode_block(struct super_block *sb,
 		goto bail;
 	}
 
+	/*
+	 * Reject dinodes whose i_mode does not name one of the seven
+	 * canonical POSIX file types.  ocfs2_populate_inode() copies
+	 * i_mode verbatim into inode->i_mode and then dispatches via
+	 * switch (mode & S_IFMT) to file/dir/symlink/special_file iops;
+	 * an unrecognised type falls into ocfs2_special_file_iops with
+	 * init_special_inode(), which interprets i_rdev.  Constrain the
+	 * type here so the dispatch only ever sees a value mkfs.ocfs2 /
+	 * VFS can produce.
+	 */
+	if (!ocfs2_valid_inode_mode(le16_to_cpu(di->i_mode))) {
+		rc = ocfs2_error(sb,
+				 "Invalid dinode #%llu: mode 0%o has unknown file type\n",
+				 (unsigned long long)bh->b_blocknr,
+				 le16_to_cpu(di->i_mode));
+		goto bail;
+	}
+
+	/*
+	 * id1.dev1.i_rdev is the device-number arm of the id1 union and
+	 * is only meaningful for character and block device inodes.  For
+	 * any other regular user-visible file type the on-disk value
+	 * must be zero.  ocfs2_populate_inode() currently runs
+	 *
+	 *     inode->i_rdev = huge_decode_dev(le64_to_cpu(fe->id1.dev1.i_rdev));
+	 *
+	 * unconditionally, before the S_IFMT switch decides whether the
+	 * inode is a special file.  As a result, an i_rdev value present
+	 * on a non-device inode is silently published into the in-core
+	 * inode; a subsequent forced re-read or in-core mode mutation
+	 * (cluster peer with raw write access to the shared LUN,
+	 * on-disk corruption, or a separately forged dinode) can then
+	 * expose the attacker-controlled device number to
+	 * init_special_inode() without ever showing an unusual i_mode
+	 * at validation time.
+	 *
+	 * System inodes (OCFS2_SYSTEM_FL) legitimately use the bitmap1
+	 * and journal1 arms of the same union (allocator i_used /
+	 * i_total counters and the journal ij_flags /
+	 * ij_recovery_generation pair); those bytes are not an i_rdev
+	 * and must not be checked here.  Restrict the cross-check to
+	 * non-system inodes, which is the full attacker-controllable
+	 * surface.
+	 */
+	if (ocfs2_dinode_has_unexpected_rdev(di)) {
+		rc = ocfs2_error(sb,
+				 "Invalid dinode #%llu: non-device mode 0%o with i_rdev %llu\n",
+				 (unsigned long long)bh->b_blocknr,
+				 le16_to_cpu(di->i_mode),
+				 (unsigned long long)le64_to_cpu(di->id1.dev1.i_rdev));
+		goto bail;
+	}
+
+	/*
+	 * Non-inline directories must not have i_size without allocated
+	 * clusters: directory growth adds storage before advancing i_size,
+	 * and readdir walks i_size block-by-block.  A forged directory
+	 * with zero clusters and a huge i_size would repeatedly fault on
+	 * holes while advancing through the claimed size.
+	 *
+	 * Non-inline regular files have the same invariant on non-sparse
+	 * volumes.  Sparse regular files are different: truncate can
+	 * legitimately grow i_size without allocating clusters, so keep
+	 * the sparse-alloc carveout for S_IFREG only.  System inodes and
+	 * inline-data dinodes have their own storage rules.
+	 */
+	if (ocfs2_dinode_has_size_without_clusters(sb, di)) {
+		if (S_ISDIR(le16_to_cpu(di->i_mode)))
+			rc = ocfs2_error(sb,
+					 "Invalid dinode #%llu: directory i_size %llu with i_clusters 0 and no inline-data flag\n",
+					 (unsigned long long)bh->b_blocknr,
+					 (unsigned long long)le64_to_cpu(di->i_size));
+		else
+			rc = ocfs2_error(sb,
+					 "Invalid dinode #%llu: regular file i_size %llu with i_clusters 0 and no inline-data flag on non-sparse volume\n",
+					 (unsigned long long)bh->b_blocknr,
+					 (unsigned long long)le64_to_cpu(di->i_size));
+		goto bail;
+	}
+
 	if (le16_to_cpu(di->i_dyn_features) & OCFS2_INLINE_DATA_FL) {
 		struct ocfs2_inline_data *data = &di->id2.i_data;
 
@@ -1525,6 +1639,29 @@ int ocfs2_validate_inode_block(struct super_block *sb,
 		}
 	}
 
+	if (S_ISLNK(le16_to_cpu(di->i_mode)) &&
+	    !le32_to_cpu(di->i_clusters)) {
+		int max_inline = ocfs2_fast_symlink_chars(sb);
+		u64 i_size = le64_to_cpu(di->i_size);
+
+		if (i_size >= max_inline) {
+			rc = ocfs2_error(sb,
+					 "Invalid dinode #%llu: fast symlink i_size %llu exceeds max %d\n",
+					 (unsigned long long)bh->b_blocknr,
+					 (unsigned long long)i_size,
+					 max_inline - 1);
+			goto bail;
+		}
+
+		if (strnlen((char *)di->id2.i_symlink, i_size + 1) != i_size) {
+			rc = ocfs2_error(sb,
+					 "Invalid dinode #%llu: fast symlink is not NUL-terminated at i_size %llu\n",
+					 (unsigned long long)bh->b_blocknr,
+					 (unsigned long long)i_size);
+			goto bail;
+		}
+	}
+
 	if (le32_to_cpu(di->i_flags) & OCFS2_CHAIN_FL) {
 		struct ocfs2_chain_list *cl = &di->id2.i_chain;
 		u16 bpc = 1 << (OCFS2_SB(sb)->s_clustersize_bits -
@@ -1559,6 +1696,38 @@ int ocfs2_validate_inode_block(struct super_block *sb,
 		goto bail;
 	}
 
+	if (ocfs2_dinode_has_extents(di)) {
+		struct ocfs2_extent_list *el = &di->id2.i_list;
+		u16 count = le16_to_cpu(el->l_count);
+		u16 next_free = le16_to_cpu(el->l_next_free_rec);
+
+		if (count == 0) {
+			rc = ocfs2_error(sb,
+					 "Invalid dinode %llu: extent list l_count is zero\n",
+					 (unsigned long long)bh->b_blocknr);
+			goto bail;
+		}
+		/*
+		 * The exact capacity depends on i_xattr_inline_size, another
+		 * unvalidated on-disk field. Inline xattrs only shrink the
+		 * list, so the no-xattr maximum is a safe upper bound that a
+		 * valid l_count never exceeds.
+		 */
+		if (count > ocfs2_extent_recs_per_inode(sb)) {
+			rc = ocfs2_error(sb,
+					 "Invalid dinode %llu: extent list l_count %u exceeds max %u\n",
+					 (unsigned long long)bh->b_blocknr, count,
+					 ocfs2_extent_recs_per_inode(sb));
+			goto bail;
+		}
+		if (next_free > count) {
+			rc = ocfs2_error(sb,
+					 "Invalid dinode %llu: extent list l_next_free_rec %u exceeds l_count %u\n",
+					 (unsigned long long)bh->b_blocknr, next_free, count);
+			goto bail;
+		}
+	}
+
 	rc = 0;
 
 bail:
@@ -1624,6 +1793,40 @@ static int ocfs2_filecheck_validate_inode_block(struct super_block *sb,
 		     (unsigned long long)bh->b_blocknr,
 		     le32_to_cpu(di->i_fs_generation));
 		rc = -OCFS2_FILECHECK_ERR_GENERATION;
+		goto bail;
+	}
+
+	if (!ocfs2_valid_inode_mode(le16_to_cpu(di->i_mode))) {
+		mlog(ML_ERROR,
+		     "Filecheck: invalid dinode #%llu: mode 0%o has unknown file type\n",
+		     (unsigned long long)bh->b_blocknr,
+		     le16_to_cpu(di->i_mode));
+		rc = -OCFS2_FILECHECK_ERR_INVALIDINO;
+		goto bail;
+	}
+
+	if (ocfs2_dinode_has_unexpected_rdev(di)) {
+		mlog(ML_ERROR,
+		     "Filecheck: invalid dinode #%llu: non-device mode 0%o with i_rdev %llu\n",
+		     (unsigned long long)bh->b_blocknr,
+		     le16_to_cpu(di->i_mode),
+		     (unsigned long long)le64_to_cpu(di->id1.dev1.i_rdev));
+		rc = -OCFS2_FILECHECK_ERR_INVALIDINO;
+		goto bail;
+	}
+
+	if (ocfs2_dinode_has_size_without_clusters(sb, di)) {
+		if (S_ISDIR(le16_to_cpu(di->i_mode)))
+			mlog(ML_ERROR,
+			     "Filecheck: invalid dinode #%llu: directory i_size %llu with i_clusters 0 and no inline-data flag\n",
+			     (unsigned long long)bh->b_blocknr,
+			     (unsigned long long)le64_to_cpu(di->i_size));
+		else
+			mlog(ML_ERROR,
+			     "Filecheck: invalid dinode #%llu: regular file i_size %llu with i_clusters 0 and no inline-data flag on non-sparse volume\n",
+			     (unsigned long long)bh->b_blocknr,
+			     (unsigned long long)le64_to_cpu(di->i_size));
+		rc = -OCFS2_FILECHECK_ERR_INVALIDINO;
 	}
 
 bail:
@@ -1812,4 +2015,3 @@ const struct ocfs2_caching_operations ocfs2_inode_caching_ops = {
 	.co_io_lock		= ocfs2_inode_cache_io_lock,
 	.co_io_unlock		= ocfs2_inode_cache_io_unlock,
 };
-