e2fsck: ignore badblocks if it says badblocks inode is bad

If the badblocks list says that the badblocks inode is bad, it's quite
likely that badblocks is broken.  Worse yet, if the root inode is in
the same block as the badblocks inode (likely since they're adjacent),
the filesystem becomes unfixable because pass3 notices the bad root
inode and exits.

So... if we encounter this case, just kill the badblocks inode.

Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

1 files changed, 31 insertions, 0 deletions

diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index 4fc53112..7175c771 100644
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -1076,6 +1076,37 @@ void e2fsck_pass1(e2fsck_t ctx)
 		if (ctx->flags & E2F_FLAG_SIGNAL_MASK)
 			return;
 		if (pctx.errcode == EXT2_ET_BAD_BLOCK_IN_INODE_TABLE) {
+			/*
+			 * If badblocks says badblocks is bad, offer to clear
+			 * the list, update the in-core bb list, and restart
+			 * the inode scan.
+			 */
+			if (ino == EXT2_BAD_INO &&
+			    fix_problem(ctx, PR_1_BADBLOCKS_IN_BADBLOCKS,
+					&pctx)) {
+				errcode_t err;
+
+				e2fsck_clear_inode(ctx, ino, inode, 0, "pass1");
+				ext2fs_badblocks_list_free(ctx->fs->badblocks);
+				ctx->fs->badblocks = NULL;
+				err = ext2fs_read_bb_inode(ctx->fs,
+							&ctx->fs->badblocks);
+				if (err) {
+					fix_problem(ctx, PR_1_ISCAN_ERROR,
+						    &pctx);
+					ctx->flags |= E2F_FLAG_ABORT;
+					goto endit;
+				}
+				err = ext2fs_inode_scan_goto_blockgroup(scan,
+									0);
+				if (err) {
+					fix_problem(ctx, PR_1_ISCAN_ERROR,
+						    &pctx);
+					ctx->flags |= E2F_FLAG_ABORT;
+					goto endit;
+				}
+				continue;
+			}
 			if (!ctx->inode_bb_map)
 				alloc_bb_map(ctx);
 			ext2fs_mark_inode_bitmap2(ctx->inode_bb_map, ino);