commit 24fcd42ff6b3eb4fb9c6d8debfbeaef8ed747062 Author: Oswald Buddenhagen <o...@users.sf.net> Date: Mon Nov 11 17:24:38 2019 +0100
handle bogus server responses more robustly don't use assert()s when the error condition can stem not only from errors in mbsync's logic, but also from the IMAP stream being corrupted. amends 72be55b0e. REFMAIL: 20191021233411.55ctuvslkfqf2pna@koblih.localdomain src/drv_imap.c | 20 ++++++++++++++++---- 1 file changed, 16 insertions(+), 4 deletions(-) diff --git a/src/drv_imap.c b/src/drv_imap.c index f06a02d..ca9081c 100644 --- a/src/drv_imap.c +++ b/src/drv_imap.c @@ -969,7 +969,7 @@ parse_fetch_rsp( imap_store_t *ctx, list_t *list, char *s ATTR_UNUSED ) msg_data_t *msgdata; imap_cmd_t *cmdp; uchar mask = 0, status = 0; - uint i, uid = 0, size = 0; + uint i, uid = 0, need_uid = 0, size = 0; time_t date = 0; if (!is_list( list )) { @@ -985,6 +985,7 @@ parse_fetch_rsp( imap_store_t *ctx, list_t *list, char *s ATTR_UNUSED ) error( "IMAP error: unable to parse UID\n" ); goto ffail; } + continue; // This *is* the UID. } else if (!strcmp( "FLAGS", tmp->val )) { tmp = tmp->next; if (is_list( tmp )) { @@ -1011,6 +1012,7 @@ parse_fetch_rsp( imap_store_t *ctx, list_t *list, char *s ATTR_UNUSED ) } } status |= M_FLAGS; + continue; // This may legitimately come without UID. } else { error( "IMAP error: unable to parse FLAGS\n" ); goto ffail; @@ -1092,17 +1094,27 @@ parse_fetch_rsp( imap_store_t *ctx, list_t *list, char *s ATTR_UNUSED ) } } } + need_uid = 1; } if (!uid) { - assert( !body && !tuid && !msgid ); + if (need_uid) { + error( "IMAP error: received payload without UID\n" ); + goto ffail; + } // Ignore async flag updates for now. } else if ((cmdp = ctx->in_progress) && cmdp->param.lastuid) { - assert( !body && !tuid && !msgid ); + if (need_uid || (status & M_FLAGS)) { + error( "IMAP error: received extraneous data in response to UID query\n" ); + goto ffail; + } // Workaround for server not sending UIDNEXT and/or APPENDUID. ctx->uidnext = uid + 1; } else if (body) { - assert( !tuid && !msgid ); + if (tuid || msgid) { // Only those that leak; ignore others. + error( "IMAP error: received extraneous data with full message\n" ); + goto ffail; + } for (cmdp = ctx->in_progress; cmdp; cmdp = cmdp->next) if (cmdp->param.uid == uid) goto gotuid; _______________________________________________ isync-devel mailing list isync-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/isync-devel