musl - musl - an implementation of the standard library for Linux-based systems

Age	Commit message (Collapse)	Author	Lines
2012-08-25	fix bug in gnu hash lookup on dlsym(handle, name) lookups	Rich Felker	-1/+1
	wrong hash was being passed; just a copy/paste error. did not affect lookups in the global namespace; this is probably why it was not caught in testing.
2012-08-25	clean up search_vec usage for vdso	Rich Felker	-2/+2

2012-08-25	use new search_vec function to find vdso in dynamic linker	Rich Felker	-4/+2

2012-08-25	ensure canary is setup if stack-prot libs are dlopen'd into non-ssp app	Rich Felker	-1/+4
	previously, this usage could lead to a crash if the thread pointer was still uninitialized, and otherwise would just cause the canary to be zero (less secure).
2012-08-25	add gnu hash support in the dynamic linker	Rich Felker	-12/+85
	based on the patches contributed by boris brezillon.
2012-08-18	make dynamic linker report all failures before exiting	Rich Felker	-2/+6
	before, only the first library that failed to load or symbol that failed to resolve was reported, and then the dynamic linker immediately exited. when attempting to fix a library compatibility issue, this is about the worst possible behavior. now we print all errors as they occur and exit at the very end if errors were encountered.
2012-08-07	fix bug dlsym bug that slipped in during dynamic linker cleanup	Rich Felker	-1/+1

2012-08-05	more changes that were lost when committing mips dynamic linker	Rich Felker	-0/+4

2012-08-05	fix change lost in the process of integrating mips dynamic linker	Rich Felker	-2/+2

2012-08-05	mips dynamic linker support	Rich Felker	-0/+3
	not heavily tested, but the basics are working. the basic concept is that the dynamic linker entry point code invokes a pure-PIC (no global accesses) C function in reloc.h to perform the early GOT relocations needed to make the dynamic linker itself functional, then invokes __dynlink like on other archs. since mips uses some ugly arch-specific hacks to optimize relocating the GOT (rather than just using the normal DT_REL[A] tables like on other archs), the dynamic linker has been modified slightly to support calling arch-specific relocation code in reloc.h. most of the actual mips-specific behavior was developed by reading the output of readelf on libc.so and simple executable files. i could not find good reference information on which relocation types need to be supported or their semantics, so it's possible that some legitimate usage cases will not work yet.
2012-08-05	more cleanup of dynamic linker internals	Rich Felker	-8/+9

2012-08-05	more dynamic linker internals cleanup	Rich Felker	-6/+6
	changing the string printed for the dso name is not a regression; the old code was simply using the wrong dso name (head rather than the dso currently being relocated). this will be fixed in a later commit.
2012-08-05	dynamic linker internals cleanup	Rich Felker	-5/+7

2012-07-13	make dynamic linker tell the debugger its own pathname	Rich Felker	-0/+5
	use the main program's PT_INTERP header if possible, since this is sure to be a correct (and hopefully absolute) pathname.
2012-07-11	make dynamic linker depend on -DSHARED not -fPIC	Rich Felker	-1/+1
	if libc.a is compiled PIC for use in static PIE code, this should not cause the dynamic linker (which still does not support static-linked main program) to be built into libc.a.
2012-07-11	fix lots of breakage on dlopen, mostly with explicit pathnames	Rich Felker	-14/+21
	most importantly, the name for such libs was being set from an uninitialized buffer. also, shortname always had an initial '/' character, making it useless for looking up already-loaded libraries by name, and thus causing repeated searches through the library path. major changes now: - shortname is the base name for library lookups with no explicit pathname. it's initially clear for libraries loaded with an explicit pathname (and for the main program), but will be set if the same library (detected via inodes match) is later found by a search. - exact name match is never used to identify libraries loaded with an explicit pathname. in this case, there's no explicit search, so we can just stat the file and check for inode match.
2012-07-07	fix dlsym RTLD_NEXT support	Rich Felker	-1/+3
	previously this was being handled the same as a library-specific, dependency-order lookup on the next library in the global chain, which is likely to be utterly meaningless. instead the lookup needs to be in the global namespace, but omitting the initial portion of the global library chain up through the calling library.
2012-06-09	fix char signedness bug (arm-specific) in dynamic linker	Rich Felker	-1/+1

2012-06-06	treat failure of mprotect in map_library as a fatal load failure	Rich Felker	-9/+9
	the error will propagate up and be printed to the user at program start time; at runtime, dlopen will just fail and leave a message for dlerror. previously, if mprotect failed, subsequent attempts to perform relocations would crash the program. this was resulting in an increasing number of false bug reports on grsec systems where rwx permission is not possible in cases where users were wrongly attempting to use non-PIC code in shared libraries. supporting that usage is in theory possible, but the x86_64 toolchain does not even support textrels, and the cost of keeping around the necessary information to handle textrels without rwx permissions is disproportionate to the benefit (which is essentially just supporting broken library setups on grsec machines). also, i unified the error-out code in map_library now that there are 3 places from which munmap might have to be called.
2012-05-27	add ldd and main program loading support to dynamic linker	Rich Felker	-21/+68

2012-05-04	fix error reporting for dlsym with global symbols	Rich Felker	-1/+2

2012-05-03	overhaul SSP support to use a real canary	Rich Felker	-4/+3
	pthread structure has been adjusted to match the glibc/GCC abi for where the canary is stored on i386 and x86_64. it will need variants for other archs to provide the added security of the canary's entropy, but even without that it still works as well as the old "minimal" ssp support. eventually such changes will be made anyway, since they are also needed for GCC/C11 thread-local storage support (not yet implemented). care is taken not to attempt initializing the thread pointer unless the program actually uses SSP (by reference to __stack_chk_fail).
2012-04-25	gdb shared library debugging support	Rich Felker	-5/+32
	provide the minimal level of dynamic linker-to-debugger glue needed to let gdb find loaded libraries and load their symbols.
2012-04-24	first attempt at enabling stack protector support	Rich Felker	-0/+7
	the code is written to pre-init the thread pointer in static linked programs that pull in __stack_chk_fail or dynamic-linked programs that lookup the symbol. no explicit canary is set; the canary will be whatever happens to be in the thread structure at the offset gcc hard-coded. this can be improved later.
2012-04-23	make dlerror produce informative results	Rich Felker	-4/+15
	note that dlerror is specified to be non-thread-safe, so no locking is performed on the error flag or message aside from the rwlock already held by dlopen or dlsym. if 2 invocations of dlsym are generating errors at the same time, they could clobber each other's results, but the resulting string, albeit corrupt, will still be null-terminated. any use of dlerror in such a situation could not be expected to give meaningful results anyway.
2012-03-23	make dlerror conform to posix	Rich Felker	-6/+16
	the error status is required to be sticky after failure of dlopen or dlsym until cleared by dlerror. applications and especially libraries should never rely on this since it is not thread-safe and subject to race conditions, but glib does anyway.
2012-02-07	protect against cancellation in dlopen	Rich Felker	-2/+5
	i'm not sure that it's "correct" for dlopen to block cancellation when calling constructors for libraries it loads, but it sure seems like the right thing. in any case, dlopen itself needs cancellation blocked.
2012-02-07	reduce some wasted space in dso structure	Rich Felker	-3/+3

2012-02-06	run ctors/dtors for shared objects loaded with dlopen	Rich Felker	-0/+1

2012-02-06	add support for init/finit (constructors and destructors)	Rich Felker	-0/+19
	this is mainly in hopes of supporting c++ (not yet possible for other reasons) but will also help applications/libraries which use (and more often, abuse) the gcc __attribute__((__constructor__)) feature in "C" code. x86_64 and arm versions of the new startup asm are untested and may have minor problems.
2012-02-03	include dummied-out dlopen and dlsym functions for static binaries	Rich Felker	-1/+10
	these don't work (or do anything at all) but at least make it possible to static link programs that insist on "having" dynamic loading support...as long as they don't actually need to use it. adding real support for dlopen/dlsym with static linking is going to be significantly more difficult...
2012-01-23	fix broken copy relocations from dynamic linker cleanup	Rich Felker	-1/+4
	this issue affected programs which use global variables exported by non-libc libraries.
2012-01-23	dynamic linker support for PIE binaries (position-independent main program)	Rich Felker	-3/+6
	even with this change, PIE will not work yet due to deficiencies in the crt1.o startup code.
2012-01-23	cleanup dynamic linker, removing some code duplication	Rich Felker	-80/+66

2012-01-20	fix dynamic linker not to depend on DYNAMIC ptr in 0th entry of GOT	Rich Felker	-3/+12
	this fixes an issue using gold instead of gnu ld for linking. it also should eliminate the need of the startup code to even load/pass the got address to the dynamic linker. based on patch submitted by sh4rm4 with minor cosmetic changes. further cleanup will follow.
2012-01-17	fix char signedness bug in dynlinker hash function	Rich Felker	-1/+2
	this only affects non-ascii symbol names, which are probably not in use anyway..
2011-09-18	disable dynamic linking/loading code in static libc builds, for now	Rich Felker	-0/+2
	it does not work, but some configure scripts will falsely detect support then generate programs that crash when they call dlopen.
2011-08-16	ldso: move the suid/secure check code closer to env/auxv processing	Rich Felker	-7/+7
	this does not change behavior, but the idea is to avoid letting other code build up between these two points, whereby the environment variables might get used before security it checked.
2011-08-16	honor AT_SECURE aux vector flag	Rich Felker	-2/+2

2011-08-16	RTLD_NEXT support	Rich Felker	-3/+8
	the asm wrapper is needed to get the return address without compiler-specific extensions.
2011-08-16	LD_PRELOAD support	Rich Felker	-0/+20

2011-07-25	when resolving symbols with only weak defs, use first def, not last def	Rich Felker	-0/+1

2011-07-24	fix resolution of weak symbols (hopefully right now) and vdso	Rich Felker	-3/+9

2011-07-24	load vdso, if present, into the dso list	Rich Felker	-2/+31

2011-07-24	simplify dynamic linker startup	Rich Felker	-23/+17
	instead of creating temp dso objects on the stack and moving them to the heap if dlopen/dlsym are used, use static objects to begin with, and just donate them to malloc if we no longer need them.
2011-07-01	fix dlopen UB due to longjmp/volatile rules violation	Rich Felker	-1/+1

2011-06-30	simple rpath support (no token expansion yet) for dynamic linker	Rich Felker	-2/+8

2011-06-29	textrel support, cheap and ugly	Rich Felker	-0/+5

2011-06-28	reclaim the memory wasted by dynamic linking for use by malloc	Rich Felker	-0/+39

2011-06-28	use load address from elf header if possible	Rich Felker	-1/+1
	this is mostly useless for shared libs (though it could help for prelink-like purposes); the intended use case is for adding support for calling the dynamic linker directly to run a program, as in: ./libc.so ./a.out foo this usage is not yet supported.