to prevent obliteration of error value from the original syscall.
Also improve error message for short read.
Submitted by: Konrad Sewiłło-Jopek
MFC after: 1 week
Differential Revision: https://reviews.freebsd.org/D27864
Currently RTLD is linked against libc_nossp_pic which means that any libc
symbol used in rtld can pull in a lot of depedencies. This was causing
symbol such as __libc_interposing and all the pthread stubs to be included
in RTLD even though they are not required. It turns out most of these
dependencies can easily be avoided by providing overrides inside of rtld.
This change is motivated by CHERI, where we have an experimental ABI that
requires additional relocation processing to allow the use of function
pointers inside of rtld. Instead of adding this self-relocation code to
RTLD I attempted to remove most function pointers from RTLD and discovered
that most of them came from the libc dependencies instead of being actually
used inside rtld.
A nice side-effect of this change is that rtld is now 22% smaller on amd64.
text data bss dec hex filename
0x21eb6 0xce0 0xe60 145910 239f6 /home/alr48/ld-elf-x86.before.so.1
0x1a6ed 0x728 0xdd8 113645 1bbed /home/alr48/ld-elf-x86.after.so.1
The number of R_X86_64_RELATIVE relocations that need to be processed on
startup has also gone down from 368 to 187 (almost 50% less).
Reviewed By: kib
Differential Revision: https://reviews.freebsd.org/D20663
This is useful when lm_find() moves the match to the global mapping,
since lm_find() could be called with a same path more than once.
Reported and tested by: Andreas Longwitz <longwitz@incore.de>
Sponsored by: The FreeBSD Foundation
Approved by: re (gjb)
MFC after: 1 week
This removes the need to call munmap(2) afterwards.
MFC after: 2 weeks
Sponsored by: DARPA, AFRL
Differential Revision: https://reviews.freebsd.org/D12767
available in 32-bit compatibility mode, unconditional.
Overhaul the man page, which had evolved more by accretion than by design.
Approved by: re (gjb)
MFC after: 3 weeks
Rtld did not set FD_CLOEXEC on its internal file descriptors; therefore,
such a file descriptor may be passed to a process created by another thread
running in parallel to dlopen() or fdlopen().
No other threads are expected to be running during parsing of the hints
and libmap files but the file descriptors need not be passed to child
processes so add O_CLOEXEC there as well.
This change will break fdlopen() (as used by OpenPAM) on kernels without
F_DUPFD_CLOEXEC (added in July). Note that running new userland on old
kernels is not supported.
Reviewed by: kib
include <file>:
Parse the contents of file before continuing with the current file.
includedir <dir>:
Parse the contents of every file in dir that ends in .conf before continuing
with the current file.
Any file or directory encountered while processing include or includedir
directives will be parsed exactly once, even if it is encountered multiple
times.
Reviewed by: kib, des
Approved by: des (mentor)
MFC after: 1 month
Stop using strerror(3) in rtld, which brings in msgcat and stdio.
Directly access sys_errlist array of errno messages with private
rtld_strerror() function.
Now,
$ size /libexec/ld-elf.so.1
text data bss dec hex filename
96983 2480 8744 108207 1a6af /libexec/ld-elf.so.1
Reviewed by: dim, kan
MFC after: 2 weeks
Since after r232498 the ctype macros require working access to
thread-local variables, rtld crashes when libmap.conf is present.
Use hand-made isspace1() macro which is enough to detect spaces in
libmap.conf.
Reported by: alc, lme, many on current@
Tested by: lme
Reviewed by: dim, kan
MFC after: 1 week
Another handy libmap patch. Lets you do stuff like this:
LD_LIBMAP="libpthread.so.1=libthr.so.1" mythreadedapp
If you already have a program-specific override in libmap.conf, note
that you must use a program-specific override in LD_LIBMAP:
LD_LIBMAP="[mythreadedapp],libpthread.so.1=libthr.so.1" mythreadedapp
PR: bin/74471
Submitted by: Dan Nelson <dnelson AT allantgroup.com>
MFC after: 2 weeks
eg:
[foo]
...
matches any executable 'foo'
[/usr/bin/foo/]
...
matches any executable under the directory /usr/bin/foo/
Exact matches continue to function as before.
PR: bin/66769
Submitted-by: Dan Nelson
(libmap available) and 1 for failure. Assign this return to the
global 'libmap_disable' variable in rtld.c.
This totally prevents any libmap functions from being called after
lm_init() if no config file is present.
While I'm here:
- Let lm_add() call strdup() on its own behalf.
- Use a temporary pointer when parsing constraints; only set the
constraint pointer on a totally successful match.
PR: bin/52783
Submitted by: David P. Reese Jr. <daver@gomerbud.com>
Approved by: re (rwatson)
implementation in case default one provided by rtld is
not suitable.
Consolidate various identical MD lock implementation into
a single file using appropriate machine/atomic.h.
Approved by: re (scottl)
This is an optional feature, disabled by default.
This will be useful to people testing the various POSIX threading
libraries under -CURRENT but can easily serve other needs.
