[PATCH] repair: ensure that unused superblock fields are zeroed From: Dave Chinner When we grab a superblock off disk via get_sb(), we don't know what the in-memory superblock we are filling out contained. We ned to ensure that the entire structure is returned in an initialised state regardless of which fields libxfs_sb_from_disk() populates from disk. In this case, it doesn't populate the sb_crc field, and so uninitialised values can escape through to disk on v4 filesystems because of this. This causes xfs/031 to fail on v4 filesystems. Reported-by: Eric Sandeen Signed-off-by: Dave Chinner --- repair/sb.c | 1 + 1 file changed, 1 insertion(+) diff --git a/repair/sb.c b/repair/sb.c index b111aca..d928dc0 100644 --- a/repair/sb.c +++ b/repair/sb.c @@ -518,6 +518,7 @@ get_sb(xfs_sb_t *sbp, xfs_off_t off, int size, xfs_agnumber_t agno) exit(1); } memset(buf, 0, size); + memset(sbp, 0, sizeof(*sbp)); /* try and read it first */