e2fsck: verify and correct inode checksums

Detect mismatches of the inode and checksum, and prompt the user to
fix the situation.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>

diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c
index cb56d921053496c7c3a272eca5c02f6926b21157..0aa93563d23f409c82f8fb37311f8c3c1bfb4b15 100644 (file)
--- a/e2fsck/pass1.c
+++ b/e2fsck/pass1.c
@@ -541,6 +541,40 @@ extern void e2fsck_setup_tdb_icount(e2fsck_t ctx, int flags,
                *ret = 0;
 }
 
+static errcode_t recheck_bad_inode_checksum(ext2_filsys fs, ext2_ino_t ino,
+                                           e2fsck_t ctx,
+                                           struct problem_context *pctx)
+{
+       errcode_t retval;
+       struct ext2_inode_large inode;
+
+       /*
+        * Reread inode.  If we don't see checksum error, then this inode
+        * has been fixed elsewhere.
+        */
+       retval = ext2fs_read_inode_full(fs, ino, (struct ext2_inode *)&inode,
+                                       sizeof(inode));
+       if (retval && retval != EXT2_ET_INODE_CSUM_INVALID)
+               return retval;
+       if (!retval)
+               return 0;
+
+       /*
+        * Checksum still doesn't match.  That implies that the inode passes
+        * all the sanity checks, so maybe the checksum is simply corrupt.
+        * See if the user will go for fixing that.
+        */
+       if (!fix_problem(ctx, PR_1_INODE_ONLY_CSUM_INVALID, pctx))
+               return 0;
+
+       retval = ext2fs_write_inode_full(fs, ino, (struct ext2_inode *)&inode,
+                                        sizeof(inode));
+       if (retval)
+               return retval;
+
+       return 0;
+}
+
 void e2fsck_pass1(e2fsck_t ctx)
 {
        int     i;
@@ -562,6 +596,7 @@ void e2fsck_pass1(e2fsck_t ctx)
        int             imagic_fs, extent_fs;
        int             busted_fs_time = 0;
        int             inode_size;
+       int             failed_csum = 0;
 
        init_resource_track(&rtrack, ctx->fs->io);
        clear_problem_context(&pctx);
@@ -741,7 +776,8 @@ void e2fsck_pass1(e2fsck_t ctx)
                        ext2fs_mark_inode_bitmap2(ctx->inode_used_map, ino);
                        continue;
                }
-               if (pctx.errcode) {
+               if (pctx.errcode &&
+                   pctx.errcode != EXT2_ET_INODE_CSUM_INVALID) {
                        fix_problem(ctx, PR_1_ISCAN_ERROR, &pctx);
                        ctx->flags |= E2F_FLAG_ABORT;
                        return;
@@ -751,6 +787,14 @@ void e2fsck_pass1(e2fsck_t ctx)
                pctx.ino = ino;
                pctx.inode = inode;
                ctx->stashed_ino = ino;
+
+               /* Clear corrupt inode? */
+               if (pctx.errcode == EXT2_ET_INODE_CSUM_INVALID) {
+                       if (fix_problem(ctx, PR_1_INODE_CSUM_INVALID, &pctx))
+                               goto clear_inode;
+                       failed_csum = 1;
+               }
+
                if (inode->i_links_count) {
                        pctx.errcode = ext2fs_icount_store(ctx->inode_link_info,
                                           ino, inode->i_links_count);
@@ -1147,6 +1191,20 @@ void e2fsck_pass1(e2fsck_t ctx)
                } else
                        check_blocks(ctx, &pctx, block_buf);
 
+               /*
+                * If the inode failed the checksum and the user didn't
+                * clear the inode, test the checksum again -- if it still
+                * fails, ask the user if the checksum should be corrected.
+                */
+               if (failed_csum) {
+                       pctx.errcode = recheck_bad_inode_checksum(fs, ino, ctx,
+                                                                 &pctx);
+                       if (pctx.errcode) {
+                               ctx->flags |= E2F_FLAG_ABORT;
+                               return;
+                       }
+               }
+
                if (ctx->flags & E2F_FLAG_SIGNAL_MASK)
                        return;
 

diff --git a/e2fsck/problem.c b/e2fsck/problem.c
index 977a4c81cf736e8043beb311ec8d33630acb6c84..8a29e347de2a78f670722dcf8a29dd5a3ba1cd62 100644 (file)
--- a/e2fsck/problem.c
+++ b/e2fsck/problem.c
@@ -946,6 +946,16 @@ static struct e2fsck_problem problem_table[] = {
          N_("@i %i has zero length extent\n\t(@n logical @b %c, physical @b %b)\n"),
          PROMPT_CLEAR, 0 },
 
+       /* inode checksum does not match inode */
+       { PR_1_INODE_CSUM_INVALID,
+         N_("@i %i checksum does not match @i.  "),
+         PROMPT_CLEAR, PR_PREEN_OK },
+
+       /* inode passes checks, but checksum does not match inode */
+       { PR_1_INODE_ONLY_CSUM_INVALID,
+         N_("@i %i passes checks, but checksum does not match @i.  "),
+         PROMPT_FIX, PR_PREEN_OK },
+
        /* Pass 1b errors */
 
        /* Pass 1B: Rescan for duplicate/bad blocks */

diff --git a/e2fsck/problem.h b/e2fsck/problem.h
index 1b5815bc176cd74d203fbc8a7ee9ee0908d0c432..3a0c025fe44dfbba9d3208183d6a435637a68ded 100644 (file)
--- a/e2fsck/problem.h
+++ b/e2fsck/problem.h
@@ -558,6 +558,12 @@ struct problem_context {
 /* Extent has zero length */
 #define PR_1_EXTENT_LENGTH_ZERO                0x010066
 
+/* inode checksum does not match inode */
+#define PR_1_INODE_CSUM_INVALID                0x010067
+
+/* inode passes checks, but checksum does not match inode */
+#define PR_1_INODE_ONLY_CSUM_INVALID   0x010068
+
 /*
  * Pass 1b errors
  */