- 19 4月, 2018 7 次提交
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由 Rich Felker 提交于
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由 Rich Felker 提交于
bring these functions up to date with the current idioms we use/prefer in fmemopen and fopencookie.
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由 Rich Felker 提交于
rather than manually performing pointer arithmetic to carve multiple objects out of one allocation, use a containing struct that encompasses them all.
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由 Rich Felker 提交于
assign entire struct rather than member-at-a-time. don't repeat buffer sizes; always use sizeof to ensure consistency.
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由 Rich Felker 提交于
replacement is subject to conditions on the replacement functions. they may only call functions which are async-signal-safe, as specified either by POSIX or as an implementation-defined extension. if any allocator functions are replaced, at least malloc, realloc, and free must be provided. if calloc is not provided, it will behave as malloc+memset. any of the memalign-family functions not provided will fail with ENOMEM. in order to implement the above properties, calloc and __memalign check that they are using their own malloc or free, respectively. choice to check malloc or free is based on considerations of supporting __simple_malloc. in order to make this work, calloc is split into separate versions for __simple_malloc and full malloc; commit ba819787 already did most of the split anyway, and completing it saves an extra call frame. previously, use of -Bsymbolic-functions made dynamic interposition impossible. now, we are using an explicit dynamic-list, so add allocator functions to the list. most are not referenced anyway, but all are added for completeness.
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由 Rich Felker 提交于
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由 Rich Felker 提交于
instead of using a waiters count, add a bit to the lock field indicating that the lock may have waiters. threads which obtain the lock after contending for it will perform a potentially-spurious wake when they release the lock.
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- 18 4月, 2018 7 次提交
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由 Rich Felker 提交于
commit e3bc22f1 removed all references to __brk.
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由 Rich Felker 提交于
the existing laddr function for fdpic cannot translate ELF virtual addresses outside of the LOAD segments to runtime addresses because the fdpic loadmap only covers the logically-mapped part. however the whole point of reclaim_gaps is to recover the slack space up to the page boundaries, so it needs to work with such addresses. add a new laddr_pg function that accepts any address in the page range for the LOAD segment by expanding the loadmap records out to page boundaries. only use the new version for reclaim_gaps, so as not to impact performance of other address lookups. also, only use laddr_pg for the start address of a gap; the end address lies one byte beyond the end, potentially in a different page where it would get mapped differently. instead of mapping end, apply the length (end-start) to the mapped value of start.
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由 Rich Felker 提交于
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由 Alexander Monakov 提交于
Split 'free' into unmap_chunk and bin_chunk, use the latter to introduce __malloc_donate and use it in reclaim_gaps instead of calling 'free'.
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由 Alexander Monakov 提交于
Fix an instance where realloc code would overallocate by OVERHEAD bytes amount. Manually arrange for reuse of memcpy-free-return exit sequence.
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由 Rich Felker 提交于
we have always bound symbols at libc.so link time rather than runtime to minimize startup-time relocations and overhead of calls through the PLT, and possibly also to preclude interposition that would not work correctly anyway if allowed. historically, binding at link-time was also necessary for the dynamic linker to work, but the dynamic linker bootstrap overhaul in commit f3ddd173 made it unnecessary. our use of -Bsymbolic-functions, rather than -Bsymbolic, was chosen because the latter is incompatible with public global data; it makes it incompatible with copy relocations in the main program. however, not all global data needs to be public. by using --dynamic-list instead with an explicit list, we can reduce the number of symbolic relocations left for runtime. this change will also allow us to permit interposition of specific functions (e.g. the allocator) if/when we want to, by adding them to the dynamic list.
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由 Rich Felker 提交于
the Linux SYS_nice syscall is unusable because it does not return the newly set priority. always use SYS_setpriority. also avoid overflows in addition of inc by handling large inc values directly without examining the old nice value.
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- 12 4月, 2018 2 次提交
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由 Alexander Monakov 提交于
Implementation of __malloc0 in malloc.c takes care to preserve zero pages by overwriting only non-zero data. However, malloc must have already modified auxiliary heap data just before and beyond the allocated region, so we know that edge pages need not be preserved. For allocations smaller than one page, pass them immediately to memset. Otherwise, use memset to handle partial pages at the head and tail of the allocation, and scan complete pages in the interior. Optimize the scanning loop by processing 16 bytes per iteration and handling rest of page via memset as soon as a non-zero byte is found.
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由 Rich Felker 提交于
the catan implementation from OpenBSD includes a FIXME-annotated "overflow" branch that produces a meaningless and incorrect large-magnitude result. it was reachable via three paths, corresponding to gotos removed by this commit, in order: 1. pure imaginary argument with imaginary component greater than 1 in magnitude. this case does not seem at all exceptional and is handled (at least with the quality currently expected from our complex math functions) by the existing non-exceptional code path. 2. arguments on the unit circle, including the pure-real argument 1.0. these are not exceptional except for ±i, which should produce results with infinite imaginary component and which lead to computation of atan2(±0,0) in the existing non-exceptional code path. such calls to atan2() however are well-defined by POSIX. 3. the specific argument +i. this route should be unreachable due to the above (2), but subtle rounding effects might have made it possible in rare cases. continuing on the non-exceptional code path in this case would lead to computing the (real) log of an infinite argument, then producing a NAN when multiplying it by I. for now, remove the exceptional code paths entirely. replace the multiplication by I with construction of a complex number using the CMPLX macro so that the NAN issue (3) prevented cannot arise. with these changes, catan should give reasonably correct results for real arguments, and should no longer give completely-wrong results for pure-imaginary arguments outside the interval (-i,+i).
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- 10 4月, 2018 1 次提交
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由 Rich Felker 提交于
the factor of -i noted in the comment at the top of casin.c was omitted from the actual code, yielding a result rotated 90 degrees and propagating into errors in other functions defined in terms of casin. implement multiplication by -i as a rotation of the real and imaginary parts of the result, rather than by actual multiplication, since the latter cannot be optimized without knowledge that the operand is finite. here, the rotation is the actual intent, anyway.
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- 08 4月, 2018 1 次提交
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由 Samuel Holland 提交于
Commit 8a6bd730 added support for padding specifier extensions to strftime, but did not modify wcsftime. In the process, it added a parameter to __strftime_fmt_1 in strftime.c, but failed to update the prototype in wcsftime.c. This was found by compiling musl with LTO: src/time/wcsftime.c:7:13: warning: type of '__strftime_fmt_1' does \ not match original declaration [-Wlto-type-mismatch] Fix the prototype of __strftime_fmt_1 in wcsftime.c, and generate the 'pad' argument the same way as it is done in strftime.
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- 05 4月, 2018 1 次提交
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由 Rich Felker 提交于
it was reported by Erik Bosman that poll fails without setting revents when the nfds argument exceeds the current value for RLIMIT_NOFILE, causing the subsequent open calls to be bypassed. if the rlimit is either 1 or 2, this leaves fd 0 and 1 potentially closed but openable when the application code is reached. based on a brief reading of the poll syscall documentation and code, it may be possible for poll to fail under other attacker-controlled conditions as well. if it turns out these are reasonable conditions that may happen in the real world, we may have to go back and implement fallbacks to probe each fd individually if poll fails, but for now, keep things simple and treat all poll failures as fatal.
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- 03 4月, 2018 1 次提交
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由 Szabolcs Nagy 提交于
if double precision r=x*y+z is not a half way case between two single precision floats or it is an exact result then fmaf returns (float)r. however the exactness check was wrong when |x*y| < |z| and could cause incorrectly rounded result in nearest rounding mode when r is a half way case. fmaf(-0x1.26524ep-54, -0x1.cb7868p+11, 0x1.d10f5ep-29) was incorrectly rounded up to 0x1.d117ap-29 instead of 0x1.d1179ep-29. (exact result is 0x1.d1179efffffffecp-29, r is 0x1.d1179fp-29)
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- 29 3月, 2018 1 次提交
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由 Rich Felker 提交于
commit d93c0740 added use of feature test macros without including features.h, causing a definition that should be exposed in the default profile, TSVTX, to appear only when _XOPEN_SOURCE or higher is explicitly defined.
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- 25 3月, 2018 2 次提交
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由 Rich Felker 提交于
previously, MEMOPS_SRCS failed to include arch-specific replacement files for memcpy, etc., omitting CFLAGS_MEMOPS and thereby potentially causing build failure if an arch provided C (rather than asm) replacements for these files. instead of trying to explicitly include all the files that might have arch replacements, which is prone to human error, extract final names to be used out of $(LIBC_OBJS), where the rules for arch replacements have already been applied. do the same for NOSSP_OBJS, using CRT_OBJS and LDSO_OBJS rather than repeating ourselves with $(wildcard...) and explicit pathnames again.
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由 Rich Felker 提交于
the makefile logic for these files was wrong in the out-of-tree case, but it likely only affected the "all" level of stack protector.
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- 13 3月, 2018 1 次提交
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由 Rich Felker 提交于
standing alone, both the signed and int keywords identify the same type, a (signed) int. however the C language has an exception where, when the lone keyword int is used to declare a bitfield, it's implementation-defined whether the bitfield is signed or unsigned. C11 footnote 125 extends this implementation-definedness to typedefs, and DR#315 extends it to other integer types (for which support with bitfields is implementation-defined). while reasonable ABIs (all the ones we support) define bitfields as signed by default, GCC and compatible compilers offer an option -funsigned-bitfields to change the default. while any signed types defined without explicit use of the signed keyword are affected, the stdint.h types, especially intNN_t, have a natural use in bitfields. ensure that bitfields defined with these types always have the correct signedness regardless of compiler & flags used. see also GCC PR 83294.
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- 11 3月, 2018 7 次提交
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由 Rich Felker 提交于
the output delay features (NL*, CR*, TAB*, BS*, and VT*) are XSI-shaded. VT* is in the V* namespace reservation but the rest need to be suppressed in base POSIX namespace. unfortunately this change introduces feature test macro checks into another bits header. at some point these checks should be simplified by having features.h handle the "FTM X implies Y" relationships.
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由 Rich Felker 提交于
this must have been taken from POSIX without realizing that it was meaningless. the resolution to Austin Group issue #844 removed it from the standard.
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由 Rich Felker 提交于
the F_* macros associated with the lockf function are XSI-shaded (like the lockf function itself) and should only be exposed when the function is.
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由 Rich Felker 提交于
TSVTX is XSI-shaded.
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由 Rich Felker 提交于
PAGE_SIZE, NZERO, and NL_LANGMAX are XSI-shaded.
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由 Rich Felker 提交于
align with commit c9c2cd3e.
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由 Rich Felker 提交于
PAGESIZE is actually the version defined in POSIX base, with PAGE_SIZE being in the XSI option. use PAGESIZE as the underlying definition to facilitate making exposure of PAGE_SIZE conditional.
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- 08 3月, 2018 1 次提交
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由 Rich Felker 提交于
use of MB_CUR_MAX encoded a hidden dependency on the currently active locale for the calling thread, whereas nl_langinfo_l is supposed to report for the locale passed as an argument.
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- 26 2月, 2018 1 次提交
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由 Rich Felker 提交于
general policy is that all source files defining a public API or an ABI mechanism referenced by a public header should include the public header that declares the interface, so that the compiler or analysis tools can check the consistency of the declarations. Alexander Monakov pointed out a number of violations of this principle a few years back. fix them now.
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- 25 2月, 2018 7 次提交
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由 Rich Felker 提交于
add a member of appropriate type to the fpos_t union so that accesses are well-defined. use long long instead of off_t since off_t is not always exposed in stdio.h and there's no namespace-clean alias for it. access is still performed using pointer casts rather than by naming the union member as a matter of style; to the extent possible, the naming of fields in opaque types defined in the public headers is not treated as an API contract with the implementation. access via the pointer cast is valid as long as the union has a member of matching type.
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由 Rich Felker 提交于
previously this macro used an odd if/else form instead of the more idiomatic do/while(0), making it unsafe against omission of trailing semicolon. the omission would make the following statement conditional instead of producing an error.
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由 Rich Felker 提交于
this is the idiom that's used elsewhere and should be more efficient or at least no worse.
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由 Rich Felker 提交于
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由 Rich Felker 提交于
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由 Rich Felker 提交于
they seem to be relics of e3cd6c5c where this code was refactored from a check that previously masked against (F_ERR|F_NOWR) instead of just F_NOWR.
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由 Rich Felker 提交于
formally, calling readv with a zero-length first iov component should behave identically to calling read on just the second component, but presence of a zero-length iov component has triggered bugs in some kernels and performs significantly worse than a simple read on some file types.
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