On both Linux and Hurd the __eloop_threshold() is always a constant
(40 and 32 respectively), so there is no need to always call
__sysconf (_SC_SYMLOOP_MAX) for Linux case (!SYMLOOP_MAX). To avoid
a name clash with gnulib, rename the new file min-eloop-threshold.h.
Checked on x86_64-linux-gnu and with a build for x86_64-gnu.
Reviewed-by: DJ Delorie <dj@redhat.com>
I used these shell commands:
../glibc/scripts/update-copyrights $PWD/../gnulib/build-aux/update-copyright
(cd ../glibc && git commit -am"[this commit message]")
and then ignored the output, which consisted lines saying "FOO: warning:
copyright statement not found" for each of 7061 files FOO.
I then removed trailing white space from math/tgmath.h,
support/tst-support-open-dev-null-range.c, and
sysdeps/x86_64/multiarch/strlen-vec.S, to work around the following
obscure pre-commit check failure diagnostics from Savannah. I don't
know why I run into these diagnostics whereas others evidently do not.
remote: *** 912-#endif
remote: *** 913:
remote: *** 914-
remote: *** error: lines with trailing whitespace found
...
remote: *** error: sysdeps/unix/sysv/linux/statx_cp.c: trailing lines
GNU/Hurd's readlink system call is partly implemented in userspace, which
also allocates a buffer on the stack for the result, and thus needs one
more path.
Reviewed-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Old implementation of realpath allocates a PATH_MAX using alloca for
each symlink in the path, leading to MAXSYMLINKS times PATH_MAX
maximum stack usage.
The test create a symlink with __eloop_threshold() loops and creates
a thread with minimum stack size (obtained through
support_small_stack_thread_attribute). The thread issues a stack
allocations that fill the thread allocated stack minus some slack
plus and the realpath usage (which assumes a bounded stack usage).
If realpath uses more than about 2 * PATH_MAX plus some slack it
triggers a stackoverflow.
Checked on x86_64-linux-gnu and i686-linux-gnu.
Reviewed-by: DJ Delorie <dj@redhat.com>
Adhemerval Zanella
Paul Eggert
Paul Pluzhnikov
Joseph Myers
omain GEISSLER
Samuel Thibault