e2fsck: clarify overflow link count error message

When directory link count is set to overflow value (1) but during pass 4
we find out the exact link count would fit, we either silently fix this
(which is not great because e2fsck then reports the fs was modified but
output doesn't indicate why in any way), or we report that link count is
wrong and ask whether we should fix it (in case -n option was
specified). The second case is even more misleading because it suggests
non-trivial fs corruption which then gets silently fixed on the next
run. Similarly to how we fix up other non-problems, just create a new
error message for the case directory link count is not overflown anymore
and always report it to clarify what is going on.

Reviewed-by: Andreas Dilger <adilger@dilger.ca>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
(cherry picked from commit 4ebce13292f54c96f43dcb1bd1d5b8df5dc8749d)

diff --git a/e2fsck/pass4.c b/e2fsck/pass4.c
index 10be7f87180d007fab6d6b3cc0d766e8c8dd32fa..8c2d2f1fca1234320fd28ffe65882a53aa168504 100644 (file)
--- a/e2fsck/pass4.c
+++ b/e2fsck/pass4.c
@@ -237,6 +237,8 @@ void e2fsck_pass4(e2fsck_t ctx)
                        link_counted = 1;
                }
                if (link_counted != link_count) {
+                       int fix_nlink = 0;
+
                        e2fsck_read_inode_full(ctx, i, EXT2_INODE(inode),
                                               inode_size, "pass4");
                        pctx.ino = i;
@@ -250,10 +252,20 @@ void e2fsck_pass4(e2fsck_t ctx)
                        pctx.num = link_counted;
                        /* i_link_count was previously exceeded, but no longer
                         * is, fix this but don't consider it an error */
-                       if ((isdir && link_counted > 1 &&
-                            (inode->i_flags & EXT2_INDEX_FL) &&
-                            link_count == 1 && !(ctx->options & E2F_OPT_NO)) ||
-                           fix_problem(ctx, PR_4_BAD_REF_COUNT, &pctx)) {
+                       if (isdir && link_counted > 1 &&
+                           (inode->i_flags & EXT2_INDEX_FL) &&
+                           link_count == 1) {
+                               if ((ctx->options & E2F_OPT_READONLY) == 0) {
+                                       fix_nlink =
+                                               fix_problem(ctx,
+                                                       PR_4_DIR_OVERFLOW_REF_COUNT,
+                                                       &pctx);
+                               }
+                       } else {
+                               fix_nlink = fix_problem(ctx, PR_4_BAD_REF_COUNT,
+                                               &pctx);
+                       }
+                       if (fix_nlink) {
                                inode->i_links_count = link_counted;
                                e2fsck_write_inode_full(ctx, i,
                                                        EXT2_INODE(inode),

diff --git a/e2fsck/problem.c b/e2fsck/problem.c
index 5eb5973d75e9b42d4e1f0524e60583d27a1bc856..78d66891aaa183a73e9b2220c61f9babaf3cf7a2 100644 (file)
--- a/e2fsck/problem.c
+++ b/e2fsck/problem.c
@@ -2009,6 +2009,11 @@ static struct e2fsck_problem problem_table[] = {
          N_("@d exceeds max links, but no DIR_NLINK feature in @S.\n"),
          PROMPT_FIX, 0, 0, 0, 0 },
 
+       /* Directory inode ref count set to overflow but could be exact value */
+       { PR_4_DIR_OVERFLOW_REF_COUNT,
+         N_("@d @i %i ref count set to overflow but could be exact value %N.  "),
+         PROMPT_FIX, PR_PREEN_OK, 0, 0, 0 },
+
        /* Pass 5 errors */
 
        /* Pass 5: Checking group summary information */

diff --git a/e2fsck/problem.h b/e2fsck/problem.h
index 5cc89249992ee206bd3fcbc779fec0d004f29d0e..7a7294dc755c693219338d9037a9a14422b8b4fc 100644 (file)
--- a/e2fsck/problem.h
+++ b/e2fsck/problem.h
@@ -1153,6 +1153,9 @@ struct problem_context {
 /* directory exceeds max links, but no DIR_NLINK feature in superblock */
 #define PR_4_DIR_NLINK_FEATURE         0x040006
 
+/* Directory ref count set to overflow but it doesn't have to be */
+#define PR_4_DIR_OVERFLOW_REF_COUNT    0x040007
+
 /*
  * Pass 5 errors
  */