KNOWNBUGS revision 42575 
1
2
3	     K N O W N   B U G S   I N   S E N D M A I L
4			     (for 8.9.0)
5
6
7The following are bugs or deficiencies in sendmail that I am aware of
8but which have not been fixed in the current release.  You probably
9want to get the most up to date version of this from ftp.sendmail.org	
10in /pub/sendmail/KNOWNBUGS.  For descriptions of bugs that have been
11fixed, see the file RELEASE_NOTES (in the root directory of the sendmail
12distribution).
13
14This list is not guaranteed to be complete.
15
16
17* Null bytes are not handled properly in headers.
18
19  Sendmail should handle full binary data.  As it stands, it handles
20  all values in the body, but only 0x01-0x80 and 0xA0-0xFF in
21  the header.  Notably missing is 0x00, which would require a major
22  restructuring of the code -- for example, almost no C library support
23  could be used to handle strings.
24
25* Duplicate error messages.
26
27  Sometimes identical, duplicate error messages can be generated.  As
28  near as I can tell, this is rare and relatively innocuous.
29
30* $c (hop count) macro improperly set.
31
32  The $c macro is supposed to contain the current hop count, for use
33  when calling a mailer.  This macro is initialized too early, and
34  is always zero (or the value of the -c command line flag, if any).
35  This macro will probably be removed entirely in a future release;
36  I don't believe there are any mailers left that require it.
37
38* If you EXPN a list or user that has a program mailer, the output of
39  EXPN will include ``@local.host.name''.  You can't actually mail to
40  this address.  It's not clear what the right behavior is in this
41  circumstance.
42
43* \231 considered harmful.
44
45  Header addresses that have the \231 character (and possibly others
46  in the range \201 - \237) behave in odd and usually unexpected ways.
47
48* accept() problem on SVR4.
49
50  Apparently, the sendmail daemon loop (doing accept()s on the network)
51  can get into a weird state on SVR4; it starts logging ``SYSERR:
52  getrequests: accept: Protocol Error''.  The workaround is to kill
53  and restart the sendmail daemon.  We don't have an SVR4 system at
54  Berkeley that carries more than token mail load, so I can't validate
55  this.  It is likely to be a glitch in the sockets emulation, since
56  "Protocol Error" is not possible error code with Berkeley TCP/IP.
57
58  I've also had someone report the message ``sendmail: accept:
59  SIOCGPGRP failed errno 22'' on an SVR4 system.  This message is
60  not in the sendmail source code, so I assume it is also a bug
61  in the sockets emulation.  (Errno 22 is EINVAL "Invalid Argument"
62  on all the systems I have available, including Solaris 2.x.)
63  Apparently, this problem is due to linking -lc before -lsocket;
64  if you are having this problem, check your Makefile.
65
66* accept() problem on Linux.
67
68  The accept() in sendmail daemon loop can return ETIMEDOUT.  An
69  error is reported to syslog:
70
71  Jun  9 17:14:12 hostname sendmail[207]: NOQUEUE: SYSERR(root):
72			getrequests: accept: Connection timed out
73
74  "Connection timed out" is not documented as a valid return from
75  accept(2) and this was believed to be a bug in the Linux kernel.
76  Later information from the Linux kernel group states that Linux
77  2.0 kernels follow RFC1122 while sendmail follows the original BSD
78  (now POSIX 1003.1g draft) specification.  The 2.1.X and later kernels
79  will follow the POSIX draft.
80
81* Excessive mailing list nesting can run out of file descriptors.
82
83  If you have a mailing list that includes lots of other mailing
84  lists, each of which has a separate owner, you can run out of
85  file descriptors.  Each mailing list with a separate owner uses
86  one open file descriptor (prior to 8.6.6 it was three open
87  file descriptors per list).  This is particularly egregious if
88  you have your connection cache set to be large.
89
90* Connection caching breaks if you pass the port number as an argument.
91
92  If you have a definition such as:
93
94	  Mport,          P=[IPC], F=kmDFMuX, S=11/31, R=21,
95			  M=2100000, T=DNS/RFC822/SMTP,
96			  A=IPC [127.0.0.1] $h
97
98  (i.e., where $h is the port number instead of the host name) the
99  connection caching code will break because it won't notice that
100  two messages addressed to different ports should use different
101  connections.
102
103* ESMTP SIZE underestimates the size of a message
104
105  Sendmail makes no allowance for headers that it adds, nor does it
106  account for the SMTP on-the-wire \r\n expansion.  It probably doesn't
107  allow for 8->7 bit MIME conversions either.
108
109* Paths to programs being executed and the mode of program files are
110  not checked.  Essentially, the RunProgramInUnsafeDirPath and
111  RunWritableProgram bits in the DontBlameSendmail option are always
112  set.  This is not a problem if your system is well managed (that is,
113  if binaries and system directories are mode 755 instead of something
114  foolish like 777).
115
116* 8-bit data in GECOS field
117
118  If the GECOS (personal name) information in the passwd file contains
119  8-bit characters, those characters can be included in the message
120  header, which can cause problems when sending SMTP to hosts that
121  only accept 7-bit characters.
122
123* 8->7 bit MIME conversion
124
125  When sendmail is doing 8->7 bit MIME conversions, and the message
126  contains certain MIME body types that cannot be converted to 7-bit,
127  sendmail will strip the message to 7-bit.
128
129* 7->8 bit MIME conversion
130
131  If a message that is encoded as 7-bit MIME is converted to 8-bit and
132  that message when decoded is illegal (e.g., because of long lines or
133  illegal characters), sendmail can produce an illegal message.
134
135* MIME encoded full name phrases in the From: header
136
137  If a full name phrase includes characters from MustQuoteChars, sendmail  
138  will quote the entire full name phrase. If MustQuoteChars includes  
139  characters which are not special characters according to STD 11 (RFC  
140  822), this quotation can interfere with MIME encoded full name phrases. 
141  By default, sendmail includes the single quote character (') in
142  MustQuoteChars even though it is not listed as a special character in
143  STD 11.
144
145* bestmx map with -z flag truncates the list of MX hosts
146
147  A bestmx map configured with the -z flag will truncate the list
148  of MX hosts.  This prevents creation of strings which are too
149  long for ruleset parsing.  This can have an adverse effect on the
150  relay_based_on_MX feature.
151
152
153(Version 8.34, last updated 12/17/1998)
154