upstream fixes for "unexpected FETCH response"; rel 2

see https://sourceforge.net/p/isync/bugs/59/

diff --git a/isync.spec b/isync.spec
index 63bcdd7db3194752d17c6b5772aa414386937bad..5e598049d2f3b03767cfdb3247287620b2c95d56 100644 (file)
--- a/isync.spec
+++ b/isync.spec
@@ -3,12 +3,13 @@
 Summary:       Tool to synchronize IMAP4 and Maildir mailboxes
 Name:          isync
 Version:       1.4.0
-Release:       1
+Release:       2
 License:       GPL v2+
 Group:         Applications/Networking
 URL:           http://isync.sourceforge.net/
 Source0:       http://downloads.sourceforge.net/isync/%{name}-%{version}.tar.gz
 # Source0-md5: bf60773c0ec03f132aac546df9cc7b87
+Patch0:                unexpected_fetch_response.patch
 BuildRequires: autoconf
 BuildRequires: automake
 BuildRequires: cyrus-sasl-devel
@@ -27,6 +28,7 @@ is suitable for use in IMAP-disconnected mode.
 
 %prep
 %setup -q
+%patch0 -p1
 
 %build
 %{__aclocal}

diff --git a/unexpected_fetch_response.patch b/unexpected_fetch_response.patch
new file mode 100644 (file)
index 0000000..8ca55cd
--- /dev/null
+++ b/unexpected_fetch_response.patch
@@ -0,0 +1,162 @@
+From 32392adbe3fd349e18d282a4e73208c32d6bfd1b Mon Sep 17 00:00:00 2001
+From: Oswald Buddenhagen <ossi@users.sf.net>
+Date: Sun, 14 Feb 2021 21:25:26 +0100
+Subject: [PATCH 1/3] accept unsolicited FETCH responses (without payload)
+ after all
+
+while the spec says that the server SHOULD not send FETCH responses
+about STORE FLAGS when .SILENT is used, at least gmail and fastmail seem
+to do it nonetheless. also, in case of concurrent flag updates on the
+affected messages such responses can be legitimately sent.
+
+in earlier versions of mbsync this would lead to duplicate messages
+piling up in the store, though that would pose no problem at that point.
+---
+ src/drv_imap.c | 8 ++++----
+ 1 file changed, 4 insertions(+), 4 deletions(-)
+
+diff --git a/src/drv_imap.c b/src/drv_imap.c
+index 9f23e08..c270031 100644
+--- a/src/drv_imap.c
++++ b/src/drv_imap.c
+@@ -1181,7 +1181,8 @@ parse_fetch_rsp( imap_store_t *ctx, list_t *list, char *s ATTR_UNUSED )
+               for (cmdp = ctx->in_progress; cmdp; cmdp = cmdp->next)
+                       if (cmdp->param.uid == uid)
+                               goto gotuid;
+-              goto badrsp;
++              error( "IMAP error: unexpected FETCH response with BODY (UID %u)\n", uid );
++              return LIST_BAD;
+         gotuid:
+               msgdata = ((imap_cmd_fetch_msg_t *)cmdp)->msg_data;
+               msgdata->data = body->val;
+@@ -1208,9 +1209,8 @@ parse_fetch_rsp( imap_store_t *ctx, list_t *list, char *s ATTR_UNUSED )
+                       memcpy( cur->tuid, tuid, TUIDL );
+               status &= ~(M_FLAGS | M_RECENT | M_SIZE | M_HEADER);
+       } else {
+-        badrsp:
+-              error( "IMAP error: unexpected FETCH response (UID %u)\n", uid );
+-              return LIST_BAD;
++              // These may come in as a result of STORE FLAGS despite .SILENT.
++              status &= ~(M_FLAGS | M_RECENT);
+       }
+ 
+       if (status) {
+-- 
+2.30.1
+
+From 8c86f34bf0e23c719bdbe69714a48536eb26597c Mon Sep 17 00:00:00 2001
+From: Oswald Buddenhagen <ossi@users.sf.net>
+Date: Sun, 14 Feb 2021 23:06:24 +0100
+Subject: [PATCH 2/3] fix bogus continuation of IMAP list parsing
+
+on error, parse_imap_list() needs to reset the nesting level in the
+state, as imap_socket_read() uses that as an indicator whether list
+parsing is ongoing.
+---
+ src/drv_imap.c | 1 +
+ 1 file changed, 1 insertion(+)
+
+diff --git a/src/drv_imap.c b/src/drv_imap.c
+index c270031..2ade80e 100644
+--- a/src/drv_imap.c
++++ b/src/drv_imap.c
+@@ -924,6 +924,7 @@ parse_imap_list( imap_store_t *ctx, char **sp, parse_list_state_t *sts )
+       }
+   bail:
+       free_list( sts->head );
++      sts->level = 0;
+       return LIST_BAD;
+ }
+ 
+-- 
+2.30.1
+
+From 95a83c8220861185906df5b38eed589984847bfb Mon Sep 17 00:00:00 2001
+From: Oswald Buddenhagen <ossi@users.sf.net>
+Date: Sun, 14 Feb 2021 23:37:39 +0100
+Subject: [PATCH 3/3] be more tolerant of formally malformed response codes
+
+fastmail sends flags containing ']' in PERMANENTFLAGS, which is formally
+illegal. however, if we parse the embedded list before looking for the
+response code's closing ']', things work out fine.
+
+as a side effect we won't complain about similarly or completely
+malformed response codes we don't recognize at all, which may or may not
+be considered an improvement ...
+---
+ src/drv_imap.c | 29 +++++++++++++++++------------
+ 1 file changed, 17 insertions(+), 12 deletions(-)
+
+diff --git a/src/drv_imap.c b/src/drv_imap.c
+index 2ade80e..e6e4b26 100644
+--- a/src/drv_imap.c
++++ b/src/drv_imap.c
+@@ -1253,48 +1253,53 @@ parse_response_code( imap_store_t *ctx, imap_cmd_t *cmd, char *s )
+       if (!s || *s != '[')
+               return RESP_OK;         /* no response code */
+       s++;
+-      if (!(p = strchr( s, ']' ))) {
+-        bad_resp:
++      if (!(arg = next_arg( &s ))) {
+               error( "IMAP error: malformed response code\n" );
+               return RESP_CANCEL;
+       }
+-      *p++ = 0;
+-      if (!(arg = next_arg( &s )))
+-              goto bad_resp;
+       if (!strcmp( "UIDVALIDITY", arg )) {
+               if (!(arg = next_arg( &s )) ||
+-                  (ctx->uidvalidity = strtoul( arg, &earg, 10 ), *earg))
++                  (ctx->uidvalidity = strtoul( arg, &earg, 10 ), *earg != ']'))
+               {
+                       error( "IMAP error: malformed UIDVALIDITY status\n" );
+                       return RESP_CANCEL;
+               }
+       } else if (!strcmp( "UIDNEXT", arg )) {
+               if (!(arg = next_arg( &s )) ||
+-                  (ctx->uidnext = strtoul( arg, &earg, 10 ), *earg))
++                  (ctx->uidnext = strtoul( arg, &earg, 10 ), *earg != ']'))
+               {
+                       error( "IMAP error: malformed UIDNEXT status\n" );
+                       return RESP_CANCEL;
+               }
+       } else if (!strcmp( "CAPABILITY", arg )) {
++              if (!(p = strchr( s, ']' ))) {
++                      error( "IMAP error: malformed CAPABILITY status\n" );
++                      return RESP_CANCEL;
++              }
++              *p = 0;
+               parse_capability( ctx, s );
+-      } else if (!strcmp( "ALERT", arg )) {
++      } else if (!strcmp( "ALERT]", arg )) {
+               /* RFC2060 says that these messages MUST be displayed
+                * to the user
+                */
+-              for (; isspace( (uchar)*p ); p++);
+-              error( "*** IMAP ALERT *** %s\n", p );
++              if (!s) {
++                      error( "IMAP error: malformed ALERT status\n" );
++                      return RESP_CANCEL;
++              }
++              for (; isspace( (uchar)*s ); s++);
++              error( "*** IMAP ALERT *** %s\n", s );
+       } else if (cmd && !strcmp( "APPENDUID", arg )) {
+               if (!(arg = next_arg( &s )) ||
+                   (ctx->uidvalidity = strtoul( arg, &earg, 10 ), *earg) ||
+                   !(arg = next_arg( &s )) ||
+-                  (((imap_cmd_out_uid_t *)cmd)->out_uid = strtoul( arg, &earg, 10 ), *earg))
++                  (((imap_cmd_out_uid_t *)cmd)->out_uid = strtoul( arg, &earg, 10 ), *earg != ']'))
+               {
+                       error( "IMAP error: malformed APPENDUID status\n" );
+                       return RESP_CANCEL;
+               }
+       } else if (!strcmp( "PERMANENTFLAGS", arg )) {
+               parse_list_init( &ctx->parse_list_sts );
+-              if (parse_imap_list( NULL, &s, &ctx->parse_list_sts ) != LIST_OK) {
++              if (parse_imap_list( NULL, &s, &ctx->parse_list_sts ) != LIST_OK || *s != ']') {
+                       error( "IMAP error: malformed PERMANENTFLAGS status\n" );
+                       return RESP_CANCEL;
+               }
+-- 
+2.30.1
+