Andreas Schwab, le lun. 01 mai 2023 16:03:32 +0200, a ecrit: > On Mai 01 2023, Samuel Thibault wrote: > > > Andreas Schwab, le lun. 01 mai 2023 15:38:45 +0200, a ecrit: > >> On Mai 01 2023, Samuel Thibault wrote: > >> > >> > cmsg_len is supposed to be socklen_t according to standards, but it was > >> > made > >> > size_t on Linux, see BZ 16919. For ports that have it socklen_t, > >> > SIZE_MAX is > >> > too large. We can however explicitly cast it to the type of cmsg_len so > >> > it > >> > will fit according to that type. > >> > --- > >> > socket/tst-cmsghdr-skeleton.c | 2 +- > >> > 1 file changed, 1 insertion(+), 1 deletion(-) > >> > > >> > diff --git a/socket/tst-cmsghdr-skeleton.c > >> > b/socket/tst-cmsghdr-skeleton.c > >> > index 296a0a8581..9516139f87 100644 > >> > --- a/socket/tst-cmsghdr-skeleton.c > >> > +++ b/socket/tst-cmsghdr-skeleton.c > >> > @@ -49,7 +49,7 @@ RUN_TEST_FUNCNAME (CMSG_NXTHDR_IMPL) (void) > >> > /* The first header length is so big, using it would cause an > >> > overflow. */ > >> > cmsg = CMSG_FIRSTHDR (&m); > >> > TEST_VERIFY_EXIT ((char *) cmsg == cmsgbuf); > >> > - cmsg->cmsg_len = SIZE_MAX; > >> > + cmsg->cmsg_len = (__typeof (cmsg->cmsg_len)) SIZE_MAX; > >> > >> What does that fix? > > > > 64bit hurd, where cmsg_len is socklen_t as the standards require (thus > > 32bit). > > And what does it fix?
You mean the error message? The SIZE_MAX constant truncation down from 64bit to 32bit: x86_64-glibc-gnu-gcc tst-cmsghdr.c -c -std=gnu11 -fgnu89-inline -g -O2 -Wall -Wwrite-strings -Wundef -Werror -fmerge-all-constants -frounding-math -fno-stack-protector -fno-common -Wno-parentheses -Wstrict-prototypes -Wold-style-definition -fmath-errno -fPIE -I../include -I/mnt/scratch/sthibault/build-glibc/build/glibcs/x86_64-gnu/glibc/socket -I/mnt/scratch/sthibault/build-glibc/build/glibcs/x86_64-gnu/glibc -I../sysdeps/mach/hurd/x86_64 -I../sysdeps/mach/hurd/x86 -I../sysdeps/mach/hurd/x86_64/htl -I../sysdeps/mach/hurd/htl -I../sysdeps/hurd/htl -I../sysdeps/mach/htl -I../sysdeps/htl/include -I../sysdeps/htl -I../sysdeps/pthread -I../sysdeps/mach/hurd/x86/htl -I../sysdeps/x86_64/htl -I../sysdeps/x86/htl -I../sysdeps/mach/hurd -I../sysdeps/gnu -I../sysdeps/unix/bsd -I../sysdeps/unix/inet -I../sysdeps/mach/x86_64 -I../sysdeps/mach/x86 -I../sysdeps/mach/include -I../sysdeps/mach -I../sysdeps/x86_64/64 -I../sysdeps/x86_64/fpu/multiarch -I../sysdeps/x86_64/fpu -I../sysdeps/x86/fpu -I../sysdeps/x86_64/multiarch -I../sysdeps/x86_64 -I../sysdeps/x86/include -I../sysdeps/x86 -I../sysdeps/ieee754/float128 -I../sysdeps/ieee754/ldbl-96/include -I../sysdeps/ieee754/ldbl-96 -I../sysdeps/ieee754/dbl-64 -I../sysdeps/ieee754/flt-32 -I../sysdeps/hurd/include -I../sysdeps/hurd -I../sysdeps/unix -I../sysdeps/posix -I../sysdeps/wordsize-64 -I../sysdeps/ieee754 -I../sysdeps/generic -I../hurd -I/mnt/scratch/sthibault/build-glibc/build/glibcs/x86_64-gnu/glibc/hurd/ -I../mach -I/mnt/scratch/sthibault/build-glibc/build/glibcs/x86_64-gnu/glibc/mach/ -I.. -I../libio -I. -D_LIBC_REENTRANT -include /mnt/scratch/sthibault/build-glibc/build/glibcs/x86_64-gnu/glibc/libc-modules.h -DMODULE_NAME=testsuite -include ../include/libc-symbols.h -DPIC -DTOP_NAMESPACE=glibc -o /mnt/scratch/sthibault/build-glibc/build/glibcs/x86_64-gnu/glibc/socket/tst-cmsghdr.o -MD -MP -MF /mnt/scratch/sthibault/build-glibc/build/glibcs/x86_64-gnu/glibc/socket/tst-cmsghdr.o.dt -MT /mnt/scratch/sthibault/build-glibc/build/glibcs/x86_64-gnu/glibc/socket/tst-cmsghdr.o In file included from ../include/stdint.h:1, from tst-cmsghdr-skeleton.c:24, from tst-cmsghdr.c:31: tst-cmsghdr-skeleton.c: In function 'run_test_CMSG_NXTHDR': ../stdlib/stdint.h:227:33: error: conversion from 'long unsigned int' to 'socklen_t' {aka 'unsigned int'} changes value from '18446744073709551615' to '4294967295' [-Werror=overflow] 227 | # define SIZE_MAX (18446744073709551615UL) | ^ tst-cmsghdr-skeleton.c:52:20: note: in expansion of macro 'SIZE_MAX' 52 | cmsg->cmsg_len = SIZE_MAX; | ^~~~~~~~ Samuel