From c77f203a510d27ab08729454bc865547c6111d02 Mon Sep 17 00:00:00 2001

From: =?UTF-8?q?Zbigniew=20J=C4=99drzejewski-Szmek?= <zbyszek@in.waw.pl>

Date: Thu, 27 Feb 2014 00:07:29 -0500

Subject: [PATCH] journal: assume that next entry is after previous entry

With a corrupted file, we can get in a situation where two entries

in the entry array point to the same object. Then journal_file_next_entry

will find the first one using generic_arrray_bisect, and try to move to

the second one, but since the address is the same, generic_array_get will

return the first one. journal_file_next_entry ends up in an infinite loop.

https://bugzilla.redhat.com/show_bug.cgi?id=1047039

(cherry picked from commit fb099c8d2af6620db2709e826a258089d10cdfe8)

---

 src/journal/journal-file.c | 26 ++++++++++++++++++++------

 1 file changed, 20 insertions(+), 6 deletions(-)

diff --git a/src/journal/journal-file.c b/src/journal/journal-file.c

index 23c4d28..c27289c 100644

--- a/src/journal/journal-file.c

+++ b/src/journal/journal-file.c

@@ -1359,7 +1359,7 @@ int journal_file_append_entry(JournalFile *f, const dual_timestamp *ts, const st

 }

 typedef struct ChainCacheItem {

-        uint64_t first; /* the array at the begin of the chain */

+        uint64_t first; /* the array at the beginning of the chain */

         uint64_t array; /* the cached array */

         uint64_t begin; /* the first item in the cached array */

         uint64_t total; /* the total number of items in all arrays before this one in the chain */

@@ -1945,7 +1945,7 @@ int journal_file_next_entry(

                 direction_t direction,

                 Object **ret, uint64_t *offset) {

-        uint64_t i, n;

+        uint64_t i, n, ofs;

         int r;

         assert(f);

@@ -1986,10 +1986,24 @@ int journal_file_next_entry(

         }

         /* And jump to it */

-        return generic_array_get(f,

-                                 le64toh(f->header->entry_array_offset),

-                                 i,

-                                 ret, offset);

+        r = generic_array_get(f,

+                              le64toh(f->header->entry_array_offset),

+                              i,

+                              ret, &ofs;;

+        if (r <= 0)

+                return r;

+

+        if (p > 0 &&

+            (direction == DIRECTION_DOWN ? ofs <= p : ofs >= p)) {

+                log_debug("%s: entry array corrupted at entry %"PRIu64,

+                          f->path, i);

+                return -EBADMSG;

+        }

+

+        if (offset)

+                *offset = ofs;

+

+        return 1;

 }

 int journal_file_skip_entry(