the beginning of the GOT, so we don't need an extra one here. Also, remove a
bogus comment -- we do in fact have to do fixups, because there are pointers in
ld.elf_so's data segment that need to be relocated.
first entry, which is a special case) in rtld_start, because they could be
all 0s. Instead we use the difference between the real _DYNAMIC address
(which we can determine on 68k with a "lea (%pc,_DYNAMIC),..." and the
base-relative one (at the beginning of the GOT) to figure out the relocation
offset.
Not needed for binutils-current, but I might as well fix it now.
disassembling a call to _DYNAMIC to determine its real address, and using the
first entry of the GOT as its base-relative address.
It's evil, but it works.
calls pututxline() with ruid = 0, euid = current-ftp-user. This ends
up calling update_utmp:
- if the real uid is root, don't do password or tty ownership checks
- if we cannot open the tty line, assume that it is a daemon that does
not use ttys and allow it to change a live entry to a dead one if
indeed it is the same process that created the entry.
ftpd_login(), ftpd_logout() and ftpd_logwtmp() respectively.
(makes utmp support much easier in tnftpd).
per suggestion in mail from Mike Heffner <mheffner@vt.edu>, who
forwarded patch from Michael Ranner <mranner@inode.at>.
(there are still some details to work out) but expect that to go
away soon. To support these basic changes (creation of lfs_putpages,
lfs_gop_write, mods to lfs_balloc) several other changes were made, to
wit:
* Create a writer daemon kernel thread whose purpose is to handle page
writes for the pagedaemon, but which also takes over some of the
functions of lfs_check(). This thread is started the first time an
LFS is mounted.
* Add a "flags" parameter to GOP_SIZE. Current values are
GOP_SIZE_READ, meaning that the call should return the size of the
in-core version of the file, and GOP_SIZE_WRITE, meaning that it
should return the on-disk size. One of GOP_SIZE_READ or
GOP_SIZE_WRITE must be specified.
* Instead of using malloc(...M_WAITOK) for everything, reserve enough
resources to get by and use malloc(...M_NOWAIT), using the reserves if
necessary. Use the pool subsystem for structures small enough that
this is feasible. This also obsoletes LFS_THROTTLE.
And a few that are not strictly necessary:
* Moves the LFS inode extensions off onto a separately allocated
structure; getting closer to LFS as an LKM. "Welcome to 1.6O."
* Unified GOP_ALLOC between FFS and LFS.
* Update LFS copyright headers to correct values.
* Actually cast to unsigned in lfs_shellsort, like the comment says.
* Keep track of which segments were empty before the previous
checkpoint; any segments that pass two checkpoints both dirty and
empty can be summarily cleaned. Do this. Right now lfs_segclean
still works, but this should be turned into an effectless
compatibility syscall.
on <security@freebsd.org>, and subsequently in FreeBSD's cvs repository
as libexec/ftpd/ftpd.c rev 1.133:
The FTP daemon was vulnerable to a DoS where an attacker could bind()
up port 20 for an extended period of time and thus lock out all other
users from establishing PORT data connections. Don't hold on to the
bind() while we loop around waiting to see if we can make our
connection.
Bump version to 20030122.
PLT entries are 12 bytes. Add a #define for that and replace the
explicit values with the PLT_ENTRY_SIZE. This bug can cause random
SIGILL signals to happen.
without search permission. This confused some ftp clients.
We fix this problem by maitaining a cached path when getcwd() does not work.
The symbolic links and ../ are resolved in the cached path, and it is finnally
checked for accuracy by comparing ./ and the cached path with stat (device
and inode comparison). If the comparison fails, pwd fails as it did before,
and if the comparison succeeds, the cached path is displayed.
If paths are too long, we should just compare ./ with a truncated path and
fail, thus making pwd displaying an error as it did before.
strcmp() by performing path name length comparison first. In the test
with Mozilla, the number was reduced to 1068 from 7182 (yes, we saved
6114 strcmp()!).
- use LLT (aka 'long long type') for all numeric class parameters
- improve description of various ftpd.conf(5) options
- statcmd(): print out: mmapsize readsize writesize sendbufsize sendlowat
than -0x20000000, not -0x1f000000. Quells the endless stream
of
ld: Double word displacement -535682276, out of range
style warnings that have annoyed my once too often.
This version is now RFC 959 compliant, using a patch adapted from one
sent in by david.leonard@eecs.uq.edu.au
openbsd libexec/ftpd/ftpd.c revision 1.69.
(see RFC959 page 36)
with logwtmp(3)/logwtmpx(3)), and call correctly.
Resolves [bin/18498] by Geoff Wing, who identified that the previous
version was being called incorrectly, albiet in a different manner.
page of the object double-mapped. Not that it matters much, but someone was
whinging about it.
While I'm at it, nuke obj->phdr and obj->phsize; they're unused.
There are several optimizations here:
1) Objects on _rtld_list_main do not participate in the DAG structures
at all. This is okay because all symbols must be resolvable at
link/load time, and _rtld_list_main is always searched first, so
any references from those objects must necessarily be resolved to
other objects on _rtld_list_main.
(Making this work completely required setting obj->main a bit
earlier; hence the RTLD_MAIN hack.)
2) Objects on _rtld_list_main are not put on _rtld_list_global,
preventing an extra search.
3) A bit is used to keep track of whether an object is on
_rtld_list_global, so we don't have to do a silly linear search.
4) A small attempt is made to prevent objects being put on the DAG
lists multiple times (using a silly linear search).
The sum of this appears to be a ~10% (.3s) reduction in Mozilla's
startup time on my 800MHz box.
Also, make sure _rtld_objmain->path is always set, just to make the
debug output nicer.
and utilize it. This greatly reduces the number of calls to open(2) and
malloc(3) for programs like mozilla that depend on many shared objects
while it doesn't affect performance of small programs.
-dynamic-linker=/libexec/ld.elf_so) if the BINDIR of the program being
built is /bin or /sbin.
The reason we do this is because now all programs *except* those in
/bin and /sbin (i.e. the "special cases") match the default the compiler
uses, which is what is used for things in e.g. xsrc, pkgsrc, and other
random 3rd party programs.
This is done by decoupling where a shlib is installed from how it
is located. Two new variables, SHLIBINSTALLDIR and SHLINKINSTALLDIR,
contain the former information, and key off MKDYNAMICROOT only. SHLIBDIR
and SHLINKDIR contain the latter, and key off MKDYNAMICROOT and BINDIR.
The SHLIBINSTALLDIR, SHLIBDIR, _LIBSODIR, SHLINKINSTALLDIR, and
SHLINKDIR parameters are moved to a new <bsd.shlib.mk>; see bsd.README
for usage details.
instructions. Function calls use GOT indirection, and we only patch the
GOT.
2) The mask-comparison optimization always fails, because the saved mask
always has 0x2000 set, and the PLT stub mask never does. So, remove it.
Remove the call to _rtld_relocate_objects() completely -- except on VAX, where
we TEMPORARILY call _rtld_relocate_nonplt_objects() directly.
Also add more assertions -- ld.elf_so should never have PLT relocations.
Fix an obvious bug in the 64-bit PLT fixup: the SLLX was by 12 bits, when it
should be 32.
Fix what *appear* to be two bugs in the >32768 PLT entry stub:
* One division was wrong (/14 rather than /24).
* We need to subtract 1048576 (to make the offset relative to the beginning of
the upper section), not add it.
This path is still untested, and buggy.
way we don't have to worry about malloc() failure. Also closes
a memory leak since vis_user was never free()d. Lack of malloc()
checking pointed out by Peter Werner.
from openbsd
symbols in the global part of the symbol table, use the updated GOT entry
rather than doing a lookup. (This provides the same effect as `-z combreloc'
on other platforms -- at most one lookup is done per symbol.)
Unfortunately, it is necessary to turn off lazy binding on MIPS. As the
comment says:
* XXX DANGER WILL ROBINSON!
* You might think this is stupid, as it intentionally
* defeats lazy binding -- and you'd be right.
* Unfortunately, for lazy binding to work right, we
* need to a way to force the GOT slots used for
* function pointers to be resolved immediately. This
* is supposed to be done automatically by the linker,
* by not outputting a PLT slot and setting st_value
* to 0, but GNU ld does not do so reliably.
years now.) Use _rtld_pagesz instead of getpagesize() to determine the page
size in our local malloc(). Saves a system call.
Also, since we're now relocated early, we don't need to be careful to avoid
globals, so most of the VARPSZ hacks are eliminated.
l_addr is always supposed to be obj->relocbase -- or so says the GDB code that
uses it. So, set it to this on all platforms. It already was on VAX
explicitly, and on everything else except MIPS implicitly (because
mapbase==relocbase for all existing shlibs). For some silly/stupid reason, a
new field was created that the MIPS GDB currently uses.
Another MD #ifdef bites it.
* Rename _rtld_find_library() to _rtld_load_library(). It now calls
_rtld_load_object() if necessary to actually load the object, rather
than having the caller do it. To do this, it also takes the `mode'
argument that gets passed to _rtld_load_object().
* On a related note, remove _rtld_check_library(), and instead call
_rtld_load_object() to instead try actually loading the object. We
save two extra namei's and a bunch of redundant work (almost
literally the same code) this way.
* In _rtld_map_object(), mmap(2) the first page read-only, rather than
read(2)ing it.
* In _rtld_symlook_obj(), compare the *second* character of the symbol
name before calling strcmp(). (This first character is too
frequently `_', and turns out to not be helpful, in libc.)
* Also in _rtld_symlook_obj(), remove the bogus STT_FUNC special case
-- this also allows removing the `in_plt' argument to
_rtld_symlook_list() and _rtld_symlook_obj().
Also:
* In _rtld_obj_from_addr(), rather than trying to look up `_end' in
the each object, instead use obj->mapsize as the upper bound.
buffer that is smaller in size than the source buffer.
also, there is no guarantee that any of the string components of
the request packet are null terminated.
in some cases, not all elements of the response buffer are
explicitly set. specifically pad and addr. a talk client can spy to
see which host is talking to which host by sending out regular
packets, to which talkd responds without clearing the addr element.
from xs@kittenz.org
order of DT_PLTREL and DT_JMPREL is irrelevant. Removes the need for yet
another weird #ifdef.
Also, be slightly more careful with the rel(a)lim trimming.
from the glue code in _rtld_start(). This is used to set objself.relocbase,
rather than assuming that it's the same as objself.mapbase (or 0 on MIPS).
Now -- with a bug fix to the kernel -- ld.elf_so can be linked at any VMA.
Allows /etc/ftpchroot to work correctly for usernames > 9 characters.
Noted by Max Khon in the freebsd-stable mailing list, via Thomas Vogt in
private email.
_rtld_relocate_nonplt_self(), which is called from _rtld_start.
Now we're completely relocated before main() is called.
We also no longer need _GOT_END_, so junk the ld script.
This code assumes that ld.elf_so only contains RELATIVE relocs, but that's
supposed to be the case for -Bsymbolic anyway.
This is somewhat of a hack, but I find it better than having
to run env(1) from inetd(8), or changing the environment for
inetd(8) itself (and thus all daemons started by it).
* Add a ld.so.script that exports _GOT_END_.
* Prebind the GOT in _rtld_start.
* Skip over GOT relocs in _rtld_relocate_nonplt_objects().
This makes debugging work better at least.
Large programs need multiple GOTs. The lazy binding stub in the PLT
can be reached from any of these GOTs, but the dynamic linker only
has enough information to fix up the first GOT entry. Thus, calls
through the other GOTs went through the time-consuming lazy binding
process on every call.
This fix rewrites the PLT entries themselves to bypass the lazy binding
for those GOT entries that the dynamic linker can't fixup.
Fix from FreeBSD.
Note that now that we patch up the PLT, we need to put back the "imb"
that was removed from the binder exit path.
indicates whether we're relocating ld.elf_so itself. Use this in some places
rather than hackish tests on `dodebug'. (The Alpha and HPPA `dodebug' tests
were actually noops, because RTLD_RELOCATE_SELF is not set, and therefore
dodebug is always true.)
executable was of type ET_DYN. Use this instead of `mainprog' to determine
whether we need to do base-relative fixups of the PLT. (This allows loading
non-relocatable objects, should we desire to do that at some point...)
* _rtld_relocate_plt_lazy() fixes up all the relocs pointing to the PLT. (On
most platforms it just does a simple base-relative fixup; on SPARC it does
nothing.)
* _rtld_relocate_plt_object() does immediate binding for a PLT entry.
The basic gist is that this saves a bit of time on SPARC (where the iteration
through the pltrela table was gratuitous), and a little less time on all other
platforms. A whole lot of #ifdef'ed crap is moved out of reloc.c, too.
NOT tested on: hppa sh x86_64
symbol' errors, probably because the increment gets interrupted occasionally by
a signal. In general, _rtld_bind() should not modify ANY internal state.
wiz