about summary refs log tree commit diff
path: root/src
Commit message (Collapse)AuthorAgeFilesLines
...
* avoid malloc failure for small requests when brk can't be extendedRich Felker2014-04-021-1/+23
| | | | | | | | | | | | | | | | | this issue mainly affects PIE binaries and execution of programs via direct invocation of the dynamic linker binary: depending on kernel behavior, in these cases the initial brk may be placed at at location where it cannot be extended, due to conflicting adjacent maps. when brk fails, mmap is used instead to expand the heap. in order to avoid expensive bookkeeping for managing fragmentation by merging these new heap regions, the minimum size for new heap regions increases exponentially in the number of regions. this limits the number of regions, and thereby the number of fixed fragmentation points, to a quantity which is logarithmic with respect to the size of virtual address space and thus negligible. the exponential growth is tuned so as to avoid expanding the heap by more than approximately 50% of its current total size.
* remove lazy ssp initializationTimo Teräs2014-03-253-28/+5
| | | | | | | | now that thread pointer is initialized always, ssp canary initialization can be done unconditionally. this simplifies the ldso as it does not try to detect ssp usage, and the init function itself as it is always called exactly once. this also merges ssp init path for shared and static linking.
* if dynamic linker's relro mprotect call fails, include reason in messageRich Felker2014-03-251-1/+1
|
* cosmetic improvements in dynamic linker cleanupRich Felker2014-03-251-5/+5
| | | | consistent use of braces in if/else structure, line length.
* clean up internal dynamic linker functions enumerating phdrsTimo Teräs2014-03-251-28/+23
| | | | | | | | record phentsize in struct dso, so the phdrs can be easily enumerated via it. simplify all functions enumerating phdrs to require only struct dso. also merge find_map_range and find_dso to kernel_mapped_dso function that does both tasks during single phdr enumeration.
* implement PT_GNU_RELRO supportTimo Teräs2014-03-251-15/+37
|
* fix pointer type mismatch and misplacement of constRich Felker2014-03-241-2/+2
|
* fix confstr return valueTimo Teräs2014-03-241-1/+1
| | | | per the specification, the terminating null byte is counted.
* always initialize thread pointer at program startRich Felker2014-03-2414-98/+118
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | this is the first step in an overhaul aimed at greatly simplifying and optimizing everything dealing with thread-local state. previously, the thread pointer was initialized lazily on first access, or at program startup if stack protector was in use, or at certain random places where inconsistent state could be reached if it were not initialized early. while believed to be fully correct, the logic was fragile and non-obvious. in the first phase of the thread pointer overhaul, support is retained (and in some cases improved) for systems/situation where loading the thread pointer fails, e.g. old kernels. some notes on specific changes: - the confusing use of libc.main_thread as an indicator that the thread pointer is initialized is eliminated in favor of an explicit has_thread_pointer predicate. - sigaction no longer needs to ensure that the thread pointer is initialized before installing a signal handler (this was needed to prevent a situation where the signal handler caused the thread pointer to be initialized and the subsequent sigreturn cleared it again) but it still needs to ensure that implementation-internal thread-related signals are not blocked. - pthread tsd initialization for the main thread is deferred in a new manner to minimize bloat in the static-linked __init_tp code. - pthread_setcancelstate no longer needs special handling for the situation before the thread pointer is initialized. it simply fails on systems that cannot support a thread pointer, which are non-conforming anyway. - pthread_cleanup_push/pop now check for missing thread pointer and nop themselves out in this case, so stdio no longer needs to avoid the cancellable path when the thread pointer is not available. a number of cases remain where certain interfaces may crash if the system does not support a thread pointer. at this point, these should be limited to pthread interfaces, and the number of such cases should be fewer than before.
* reduce static linking overhead from TLS support by inlining mmap syscallRich Felker2014-03-231-1/+9
| | | | | | | | | | the external mmap function is heavy because it has to handle error reporting that the kernel cannot do, and has to do some locking for arcane race-condition-avoidance purposes. for allocating initial TLS, we do not need any of that; the raw syscall suffices. on i386, this change shaves off 13% of the size of .text for the empty program.
* include header that declares __syscall_ret where it's definedRich Felker2014-03-231-0/+1
| | | | | | | | | | | | in general, we aim to always include the header that's declaring a function before defining it so that the compiler can check that prototypes match. additionally, the internal syscall.h declares __syscall_ret with a visibility attribute to improve code generation for shared libc (to prevent gratuitous GOT-register loads). this declaration should be visible at the point where __syscall_ret is defined, too, or the inconsistency could theoretically lead to problems at link-time.
* fix mips sigsetjmp asm to match fixed jmp_buf sizeRich Felker2014-03-181-1/+1
| | | | this was missed in the previous commit.
* use syscall_arg_t for arguments in public syscall() functionRich Felker2014-03-181-7/+7
| | | | | | | on x32, this change allows programs which use syscall() with pointers or 64-bit values as arguments to work correctly, i.e. without truncation or incorrect sign extension. on all other supported archs, syscall_arg_t is defined as long, so this change is a no-op.
* fix negated error codes from ptsname_rRich Felker2014-03-171-1/+1
| | | | | | the incorrect error codes also made their way into errno when __ptsname_r was called by plain ptsname, which reports errors via errno rather than a return value.
* semctl: fix UB causing crashes on powerpcrofl0r2014-03-131-4/+8
| | | | | | | | it's UB to fetch variadic args when none are passed, and this caused real crashes on ppc due to its calling convention, which defines that for variadic functions aggregate types be passed as pointers. the assignment caused that pointer to get dereferenced, resulting in a crash.
* fix incorrect rounding in printf floating point corner casesRich Felker2014-03-091-2/+2
| | | | | | | | | | | | | | the printf floating point formatting code contains an optimization to avoid computing digits that will be thrown away by rounding at the specified (or default) precision. while it was correctly retaining all places up to the last decimal place to be printed, it was not retaining enough precision to see the next nonzero decimal place in all cases. this could cause incorrect rounding down in round-to-even (default) rounding mode, for example, when printing 0.5+DBL_EPSILON with "%.0f". in the fix, LDBL_MANT_DIG/3 is a lazy (non-sharp) upper bound on the number of zeros between any two nonzero decimal digits.
* fix buffer overflow in printf formatting of denormals with low bit setRich Felker2014-03-091-1/+2
| | | | | | | | | | | empirically the overflow was an off-by-one, and it did not seem to be overwriting meaningful data. rather than simply increasing the buffer size by one, however, I have attempted to make the size obviously correct in terms of bounds on the number of iterations for the loops that fill the buffer. this still results in no more than a negligible size increase of the buffer on the stack (6-7 32-bit slots) and is a "safer" fix unless/until somebody wants to do the proof that a smaller buffer would suffice.
* in fcntl, use unsigned long instead of long for variadic argument typeRich Felker2014-03-071-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | neither is correct; different commands take different argument types, and some take no arguments at all. I have a much larger overhaul of fcntl prepared to address this, but it's not appropriate to commit during freeze. the immediate problem being addressed affects forward-compatibility on x32: if new commands are added and they take pointers, but the libc-level fcntl function is not aware of them, using long would sign-extend the pointer to 64 bits and give the kernel an invalid pointer. on the kernel side, the argument to fcntl is always treated as unsigned long, so no harm is done by treating possibly-signed integer arguments as unsigned. for every command that takes an integer argument except for F_SETOWN, large integer arguments and negative arguments are handled identically anyway. in the case of F_SETOWN, the kernel is responsible for converting the argument which it received as unsigned long to int, so the sign of negative arguments is recovered. the other problem that will be addressed later is that the type passed to va_arg does not match the type in the caller of fcntl. an advanced compiler doing cross-translation-unit analysis could potentially see this mismatch and issue warnings or otherwise make trouble. on i386, this patch was confirmed not to alter the code generated by gcc 4.7.3. in principle the generated code should not be affected on any arch except x32.
* x32: fix sysinfo()rofl0r2014-03-061-0/+5
| | | | | | | | the kernel uses long longs in the struct, but the documentation says they're long. so we need to fixup the mismatch between the userspace and kernelspace structs. since the struct offers a mem_unit member, we can avoid truncation by adjusting that value.
* fix strerror on mips: one error code is out of the 8-bit table rangeRich Felker2014-03-051-1/+7
| | | | | | | if we ever encounter other targets where error codes don't fit in the 8-bit range, the table should probably just be bumped to 16-bit, but for now I don't want to increase the table size on all archs just because of a bug in the mips abi.
* add nofpu subarchs to the sh arch, and properly detect compiler's fpu configRich Felker2014-02-278-0/+49
|
* rename superh port to "sh" for consistencyRich Felker2014-02-2713-0/+0
| | | | | | | | | linux, gcc, etc. all use "sh" as the name for the superh arch. there was already some inconsistency internally in musl: the dynamic linker was searching for "ld-musl-sh.path" as its path file despite its own name being "ld-musl-superh.so.1". there was some sentiment in both directions as to how to resolve the inconsistency, but overall "sh" was favored.
* fix readdir not to set ENOENT when directory is removed while readingRich Felker2014-02-251-2/+7
| | | | | | | | | | | | | | | | | per POSIX, ENOENT is reserved for invalid stream position; it is an optional error and would only happen if the application performs invalid seeks on the underlying file descriptor. however, linux's getdents syscall also returns ENOENT if the directory was removed between the time it was opened and the time of the read. we need to catch this case and remap it to simple end-of-file condition (null pointer return value like an error, but no change to errno). this issue reportedly affects GNU make in certain corner cases. rather than backing up and restoring errno, I've just changed the syscall to be made in a way that doesn't affect errno (via an inline syscall rather than a call to the __getdents function). the latter still exists for the purpose of providing the public getdents alias which sets errno.
* add missing sub files for mipsel-sf to use softfloat codeRich Felker2014-02-243-0/+3
| | | | | | the build system has no automatic way to know this code applies to both big (default) and little endian variants, so explicit .sub files are needed.
* mips: add mips-sf subarch support (soft-float)Szabolcs Nagy2014-02-245-0/+53
| | | | | | | | | Userspace emulated floating-point (gcc -msoft-float) is not compatible with the default mips abi (assumes an FPU or in kernel emulation of it). Soft vs hard float abi should not be mixed, __mips_soft_float is checked in musl's configure script and there is no runtime check. The -sf subarch does not save/restore floating-point registers in setjmp/longjmp and only provides dummy fenv implementation.
* superh portBobby Bingham2014-02-2313-0/+374
|
* mostly-cosmetic fixups to x32 port mergeRich Felker2014-02-233-11/+11
|
* x32 port (diff against vanilla x86_64)rofl0r2014-02-2326-114/+120
|
* import vanilla x86_64 code as x32rofl0r2014-02-2343-0/+675
|
* use syscall_arg_t type for syscall prototypes in pthread coderofl0r2014-02-222-3/+8
|
* internal/syscall.h: add syscall_arg_t macrorofl0r2014-02-221-6/+11
| | | | | | | some 32-on-64 archs require that the actual syscall args be long long. in that case syscall_arch.h can define syscall_arg_t to whatever it needs and syscall.h picks it up. all other archs just use long as usual.
* internal/syscall.h: use a macro for the syscall args castsrofl0r2014-02-221-13/+17
| | | | | | | this allows syscall_arch.h to define the macro __scc if special casting is needed, as is the case for x32, where the actual syscall arguments are 64bit, but, in case of pointers, would get sign-extended and thus become invalid.
* add fallback emulation for accept4 on old kernelsRich Felker2014-02-211-1/+12
| | | | | | | | | | | | the other atomic FD_CLOEXEC interfaces (dup3, pipe2, socket) already had such emulation in place. the justification for doing the emulation here is the same as for the other functions: it allows applications to simply use accept4 rather than having to have their own fallback code for ENOSYS/EINVAL (which one you get is arch-specific!) and there is no reasonable way an application could benefit from knowing the operation is emulated/non-atomic since there is no workaround at the application level for non-atomicity (that is the whole reason these interfaces were added).
* add ipv6 and icmpv6 to getprotoent-family functionsRich Felker2014-02-131-1/+3
| | | | based on patch by orc.
* fix typo in table for getprotoent that caused out-of-bound readsRich Felker2014-02-131-1/+1
| | | | | | | | this was unlikely to lead to any crash or dangerous behavior, but caused adjacent string constants to be treated as part of the protocols table, possibly returning nonsensical results for unknown protocol names/numbers or when getprotoent was called in a loop to enumerate all protocols.
* make posix_spawn accept null pid pointer argumentsRich Felker2014-02-121-1/+1
| | | | this is a requirement in the specification that was overlooked.
* clone: make clone a wrapper around __cloneBobby Bingham2014-02-096-18/+22
| | | | | | | | | | | | The architecture-specific assembly versions of clone did not set errno on failure, which is inconsistent with glibc. __clone still returns the error via its return value, and clone is now a wrapper that sets errno as needed. The public clone has also been moved to src/linux, as it's not directly related to the pthreads API. __clone is called by pthread_create, which does not report errors via errno. Though not strictly necessary, it's nice to avoid clobbering errno here.
* fix fesetenv(FE_DFL_ENV) on x86_64 (see previous commit)Szabolcs Nagy2014-02-091-1/+1
|
* fix fesetenv(FE_DFL_ENV) on i386Szabolcs Nagy2014-02-091-1/+1
| | | | | | | | | | | the default fenv was not set up properly, in particular the tag word that indicates the contents of the x87 registers was set to 0 (used) instead of 0xffff (empty) this could cause random crashes after setting the default fenv because it corrupted the fpu stack and then any float computation gives NaN result breaking the program logic (usually after a float to integer conversion).
* in fdopen, avoid setting O_APPEND flag if it's already setRich Felker2014-02-071-1/+2
| | | | | | | this saves a syscall in the case where the underlying open already took place with O_APPEND, which is common because fopen with append modes sets O_APPEND at the time of open before passing the file descriptor to __fdopen.
* fix ftello result for append streams with unflushed outputRich Felker2014-02-073-1/+5
| | | | | | | | | | | | | | | | | | | | | | when there is unflushed output, ftello (and ftell) compute the logical stream position as the underlying file descriptor's offset plus an adjustment for the amount of buffered data. however, this can give the wrong result for append-mode streams where the unflushed writes should adjust the logical position to be at the end of the file, as if a seek to end-of-file takes place before the write. the solution turns out to be a simple trick: when ftello (indirectly) calls lseek to determine the current file offset, use SEEK_END instead of SEEK_CUR if the stream is append-mode and there's unwritten buffered data. the ISO C rules regarding switching between reading and writing for a stream opened in an update mode, along with the POSIX rules regarding switching "active handles", conveniently leave undefined the hypothetical usage cases where this fix might lead to observably incorrect offsets. the bug being fixed was discovered via the test case for glibc issue
* add legacy functions setkey() and encrypt()Timo Teräs2014-02-052-6/+66
|
* fix nftw FTW_MOUNT flagRich Felker2014-02-011-2/+1
| | | | | the incorrect check for crossing device boundaries was preventing nftw from traversing anything except the initially provided pathname.
* fix an overflow in wcsxfrm when n==0Szabolcs Nagy2014-01-231-2/+4
| | | | posix allows zero length destination
* fix crash in dynamic linker when certain copy relocations are unsatisfiedRich Felker2014-01-211-1/+2
| | | | | | | | | | | | | | | | | | | | | STB_WEAK is only a weak reference for undefined symbols (those with a section of SHN_UNDEF). otherwise, it's a weak definition. normally this distinction would not matter, since a relocation referencing a symbol that also provides a definition (not SHN_UNDEF) will always succeed in finding the referenced symbol itself. however, in the case of copy relocations, the referenced symbol itself is ignored in order to search for another symbol to copy from, and thus it's possible that no definition is found. in this case, if the symbol being resolved happened to be a weak definition, it was misinterpreted as a weak reference, suppressing the error path and causing a crash when the copy relocation was performed with a null source pointer passed to memcpy. there are almost certainly still situations in which invalid combinations of symbol and relocation types can cause the dynamic linker to crash (this is pretty much inevitable), but the intent is that crashes not be possible for symbol/relocation tables produced by a valid linker.
* fix initstate to make the state buffer usable in setstateSzabolcs Nagy2014-01-211-12/+2
| | | | | | | | | | | setstate could use the results of previous initstate or setstate calls (they return the old state buffer), but the documentation requires that an initialized state buffer should be possible to use in setstate immediately, which means that initstate should save the generator parameters in it. I also removed the copyright notice since it is present in the copyright file.
* fix inadvertent use of struct in place of union for semunRich Felker2014-01-081-3/+3
|
* add __isoc99_vfscanf weak alias to vfscanfSzabolcs Nagy2014-01-081-0/+2
| | | | | this glibc abi compatibility function was missed when the scanf aliases were added.
* math: add drem and dremf weak aliases to i386 remainder asmSzabolcs Nagy2014-01-082-0/+6
| | | | | weak_alias was only in the c code, so drem was missing on platforms where remainder is implemented in asm.
* fix type of semctl variadic argumentRich Felker2014-01-081-4/+10
| | | | | | | | | | | | | | | | | | per POSIX, the variadic argument has type union semun, which may contain a pointer or int; the type read depends on the command being issued. this allows the userspace part of the implementation to be type-correct without requiring special-casing for different commands. the kernel always expects to receive the argument interpreted as unsigned long (or equivalently, a pointer), and does its own handling of extracting the int portion from the representation, as needed. this change fixes two possible issues: most immediately, reading the argument as a (signed) long and passing it to the syscall would perform incorrect sign-extension of pointers on the upcoming x32 target. the other possible issue is that some archs may use different (user-space) argument-passing convention for unions, preventing va_arg from correctly obtaining the argument when the type long (or even unsigned long or void *) is passed to it.
generated by cgit-pink 1.4.1 (git 2.36.1) at 2024-11-16 02:59:56 +0000