fix for it.
The bug occurs when using the --as-needed flag to ld in the presence of
synthetic linker-generated symbols that reference symbols defined in
linked-to shared libraries with versioned symbols. When the only symbols
used from a library fall into this category, ld will drop the DT_NEEDED
entry for it, but retain the versioning information. This bug is best
fixed/hacked around in binutils, not in rtld.
Discussed with: kan
because calling mmap() etc. may use GOT which is not set up
yet. Use calloc() instead of mmap() in cases where this
was the case before (sparc64, powerpc, arm).
Submitted by: Dimitry Andric (dimitry andric com)
Reviewed by: kan
Approved by: ed (mentor)
lot better than what's in the tree now. Edwin tested it at a prior
employer, but can't test it today. I've found that it works a lot
better with the various uboot versions that I've used in my embedded
work. Here's the pkg-descr from the port that describes the changes:
It all started when we got some new routers, which told me the
following when trying to upload configuration or download images
from it: The TFTP server doesn't support the blocksize option.
My curiousity was triggered, it took me some reading of RFCs and
other documentation to find out what was possible and what could
be done. Was plain TFTP very simple in its handshake, TFTP with
options was kind of messy because of its backwards capability: The
first packet returned could either be an acknowledgement of options,
or the first data packet.
Going through the source code of src/libexec/tftpd and going through
the code of src/usr.bin/tftp showed that there was a lot of duplicate
code, and the addition of options would only increase the amount
of duplicate code. After all, both the client and the server can
act as a sender and receiver.
At the end, it ended up with a nearly complete rewrite of the tftp
client and server. It has been tested against the following TFTP
clients and servers:
- Itself (yay!)
- The standard FreeBSD tftp client and server
- The Fedora Core 6 tftp client and server
- Cisco router tftp client
- Extreme Networks tftp client
It supports the following RFCs:
RFC1350 - THE TFTP PROTOCOL (REVISION 2)
RFC2347 - TFTP Option Extension
RFC2348 - TFTP Blocksize Option
RFC2349 - TFTP Timeout Interval and Transfer Size Options
RFC3617 - Uniform Resource Identifier (URI) Scheme and Applicability
Statement for the Trivial File Transfer Protocol (TFTP)
It supports the following unofficial TFTP Options as described at
http://www.compuphase.com/tftp.htm:
blksize2 - Block size restricted to powers of 2, excluding protocol headers
rollover - Block counter roll-over (roll back to zero or to one)
From the tftp program point of view the following things are changed:
- New commands: "blocksize", "blocksize2", "rollover" and "options"
- Development features: "debug" and "packetdrop"
If you try this tftp/tftpd implementation, please let me know if
it works (or doesn't work) and against which implementaion so I can
get a list of confirmed working systems.
Author: Edwin Groothuis <edwin@FreeBSD.org>
64-bit quota sizes by scaling down the sizes by the minimum amount
necessary to fit in a 32-bit field and then upscale the filesystem
block size to compensate. For example, if the hard block limit is
0x300000008 then we set the hard block limit to 0xA0000002 and claim
that the blocksize is 4 * DEV_BSIZE. This will lose the minimal
amount of information thus delivering nearly correct answers.
o Use obj->tlsinitsize to determine whether there's initialized data.
o If obj->tlssize > obj->tlsinitsize, then bzero uninitialized data.
o Don't exclude variant I from the work-around in free_tls_offset().
This makes it a little easier to figure out which application was
responsible for this log entry. Ideally we should add an ut_process or
something similar.
Suggested by: Vincent Poy <vincepoy gmail com>
Also perform a small cleanup to ftpd_logwtmp(). Just use a NULL
parameter for the username to indicate a logout, instead of an empty
string.
Reported by: Alexey Shuvaev <shuvaev physik uni-wuerzburg de>
The ttyslot() function was originally part for SUSv1, marked LEGACY in
SUSv2 and removed later on. This function only makes sense when using
utmp(5), because it was used to determine the offset of the record for
the controlling TTY. It makes little sense to keep it here, because the
new utmpx file format doesn't index based on TTY slots.
Unfortunately I have to partially wreck its functionality, though. ftpd
used to keep a file descriptor to the wtmp, which allowed it to work
from within a chroot. The current utmpx implementation doesn't offer a
way to do this. Maybe we can address this in the future, if it turns out
to be a real issue.
It seems comsat stats the utmpx database each 15 seconds to see whether
it has been changed. I am changing this behaviour to look at the utmpx
database upon processing. I don't want to allow direct interference with
the database files. I also wonder whether this optimization has any
measurable performance benefit nowadays.
- It shouldn't call logwtmp(). Applications like login(1) already make
sure both login and logout entries are written to the storage.
- There's no need to restore permissions on the pseudo-terminal, since
it should be garbage collected by the kernel.
Just like bin/ and sbin/, I think setting WARNS to the highest value
possible will make it more attractive for people to fix warnings.
- The WARNS variable is set in the Makefile in the directory of the
application itself, making it more likely that it will be removed out
of curiosity to see what happens.
- New applications will most likely build with WARNS=6 out of the box,
because the author would more likely fix the warnings during
development than lower WARNS.
Unfortunately almost all apps in libexec require a lowered value of
WARNS.
Because strings are now null-terminated, I've decided to just use an
array of utmpx structures, instead of the separated strings. This means
we just copy the entire utmpx structure and point to the strings within
the structures directly.
I increased the WARNS, but it looks like it breaks certain architectures
with more strict alignment requirements (mips, sparc64, ia64).
Pointy hat to: me
One of the things I really want to do, is to get rid of the limitations
of our current utmp(5) mechanism:
- It only allows 8 byte TTY device names.
- The hostname only allows 16 bytes of storage.
I'm not a big fan of <utmpx.h>, but I think we should at least try to
add parts of it. Unfortunately we cannot implement <utmpx.h>, because we
miss various fields, such as ut_id, ut_pid, etc. The API provided by
libulog shares some similarities with <utmpx.h>, so it shouldn't be too
hard to port these applications eventually. In most simple cases, it
should just be a matter of removing the ulog_ prefix everywhere.
As a bonus, it also implements a function called ulog_login_pseudo(),
which allows unprivileged applications to write log entries, provided
they have a valid file descriptor to a pseudo-terminal master device.
libulog will allow a smoother transition to a new file format by adding
a library interface to deal with utmp/wtmp/lastlog files. I initially
thought about adding the functionality to libutil, but because I'm not
planning on keeping this library around forever, we'd better keep it
separated.
Next items on the todo list:
1. Port applications in the base system (and ports) to libulog, instead
of letting them use <utmp.h>.
2. Remove <utmp.h>, implement <utmpx.h> and reimplement this library on
top.
3. Port as many applications as possible back to <utmpx.h>.
adjustment for all virtual addresses encoded into the ELF structures of
it. PIE binary could and should be loaded at non-zero mapbase.
For sym_zero pseudosymbol used as a return value from find_symdef()
for undefined weak symbols, st_value also should be adjusted, since
_rtld_bind corrects symbol values by relocbase.
Discussed with: bz
Reviewed by: kan
Tested by: bz (i386, amd64), bsam (linux)
MFC after: some time
ELF header from the front of the file. As all other I/O on the binary
is done using mmap(), this avoids the need for seek privileges on the
file descriptor during run-time linking.
MFC after: 1 month
Sponsored by: Google
