imapc: Avoid assert-crashing if a new message's UID is smaller than next_uid.

diff --git a/src/lib-storage/index/imapc/imapc-mailbox.c b/src/lib-storage/index/imapc/imapc-mailbox.c
index 6eec33e61243ed3f4b287d9bc940f43a71685884..c1ef7fd454cc9f8cd37abfc6b5928fb14c4d8d5d 100644 (file)
--- a/src/lib-storage/index/imapc/imapc-mailbox.c
+++ b/src/lib-storage/index/imapc/imapc-mailbox.c
@@ -64,15 +64,15 @@ static void imapc_mailbox_open_finish(struct imapc_mailbox *mbox)
 {
        const struct mail_index_record *rec;
        struct imapc_seqmap *seqmap;
-       uint32_t lseq, rseq, old_count;
+       uint32_t lseq, rseq, cur_count;
 
        /* if we haven't seen FETCH reply for some messages at the end of
           mailbox they've been externally expunged. */
        imapc_mailbox_init_delayed_trans(mbox);
        seqmap = imapc_client_mailbox_get_seqmap(mbox->client_box);
 
-       old_count = mail_index_view_get_messages_count(mbox->delayed_sync_view);
-       for (lseq = old_count; lseq > 0; lseq--) {
+       cur_count = mail_index_view_get_messages_count(mbox->delayed_sync_view);
+       for (lseq = cur_count; lseq > 0; lseq--) {
                rec = mail_index_lookup(mbox->delayed_sync_view, lseq);
                if (rec->uid <= mbox->highest_seen_uid)
                        break;
@@ -198,9 +198,10 @@ static void imapc_untagged_fetch(const struct imapc_untagged_reply *reply,
        struct imapc_mail *const *mailp;
        const struct imap_arg *list, *flags_list;
        const char *atom;
+       const struct mail_index_header *old_hdr;
        const struct mail_index_record *rec = NULL;
        enum mail_flags flags;
-       uint32_t uid, old_count;
+       uint32_t uid, cur_count;
        unsigned int i, j;
        ARRAY_TYPE(const_string) keywords = ARRAY_INIT;
        bool seen_flags = FALSE;
@@ -252,8 +253,10 @@ static void imapc_untagged_fetch(const struct imapc_untagged_reply *reply,
        }
 
        imapc_mailbox_init_delayed_trans(mbox);
-       old_count = mail_index_view_get_messages_count(mbox->delayed_sync_view);
-       while (lseq <= old_count) {
+       old_hdr = mail_index_get_header(mbox->sync_view);
+
+       cur_count = mail_index_view_get_messages_count(mbox->delayed_sync_view);
+       while (lseq <= cur_count) {
                rec = mail_index_lookup(mbox->delayed_sync_view, lseq);
                if (rec->uid == uid || uid == 0)
                        break;
@@ -271,10 +274,17 @@ static void imapc_untagged_fetch(const struct imapc_untagged_reply *reply,
                mail_index_expunge(mbox->delayed_sync_trans, lseq);
                lseq++;
        }
-       if (lseq > old_count) {
-               if (uid == 0 || lseq != old_count + 1)
+       if (lseq > cur_count) {
+               if (uid == 0 || lseq != cur_count + 1)
+                       return;
+               if (uid < old_hdr->next_uid) {
+                       imapc_mailbox_set_corrupted(mbox,
+                               "Expunged message reappeared "
+                               "(uid=%u < next_uid=%u)",
+                               uid, old_hdr->next_uid);
                        return;
-               i_assert(lseq == old_count + 1);
+               }
+               i_assert(lseq == cur_count + 1);
                mail_index_append(mbox->delayed_sync_trans, uid, &lseq);
                rec = NULL;
        }