From 10f7bdebe570e42d1f7a43de4f90eda8ccb4f0da Mon Sep 17 00:00:00 2001 From: Siddhesh Poyarekar Date: Fri, 17 Dec 2021 18:35:44 +0530 Subject: [PATCH] fortify: Fix spurious warning with realpath The length and object size arguments were swapped around for realpath. Also add a smoke test so that any changes in this area get caught in future. Signed-off-by: Siddhesh Poyarekar Reviewed-by: Adhemerval Zanella (cherry picked from commit 2bbd07c715275eb6c616988925738a0517180d57) --- debug/Makefile | 3 ++- debug/tst-realpath-chk.c | 37 +++++++++++++++++++++++++++++++++++++ stdlib/bits/stdlib.h | 2 +- 3 files changed, 40 insertions(+), 2 deletions(-) create mode 100644 debug/tst-realpath-chk.c diff --git a/debug/Makefile b/debug/Makefile index 357f888246..bc37e466ee 100644 --- a/debug/Makefile +++ b/debug/Makefile @@ -108,6 +108,7 @@ CFLAGS-tst-longjmp_chk2.c += -fexceptions -fasynchronous-unwind-tables CPPFLAGS-tst-longjmp_chk2.c += -D_FORTIFY_SOURCE=1 CFLAGS-tst-longjmp_chk3.c += -fexceptions -fasynchronous-unwind-tables CPPFLAGS-tst-longjmp_chk3.c += -D_FORTIFY_SOURCE=1 +CPPFLAGS-tst-realpath-chk.c += -D_FORTIFY_SOURCE=2 # We know these tests have problems with format strings, this is what # we are testing. Disable that warning. They are also testing @@ -155,7 +156,7 @@ tests = backtrace-tst tst-longjmp_chk tst-chk1 tst-chk2 tst-chk3 \ tst-lfschk1 tst-lfschk2 tst-lfschk3 test-strcpy_chk test-stpcpy_chk \ tst-chk4 tst-chk5 tst-chk6 tst-chk7 tst-chk8 tst-lfschk4 tst-lfschk5 \ tst-lfschk6 tst-longjmp_chk2 tst-backtrace2 tst-backtrace3 \ - tst-backtrace4 tst-backtrace5 tst-backtrace6 + tst-backtrace4 tst-backtrace5 tst-backtrace6 tst-realpath-chk ifeq ($(have-ssp),yes) tests += tst-ssp-1 diff --git a/debug/tst-realpath-chk.c b/debug/tst-realpath-chk.c new file mode 100644 index 0000000000..a8fcb327c4 --- /dev/null +++ b/debug/tst-realpath-chk.c @@ -0,0 +1,37 @@ +/* Smoke test to verify that realpath does not cause spurious warnings. + Copyright The GNU Toolchain Authors. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include + +#include +#include + +static int +do_test (void) +{ +#ifdef PATH_MAX + char buf[PATH_MAX + 1]; + char *res = realpath (".", buf); + TEST_VERIFY (res == buf); +#endif + + return 0; +} + +#include diff --git a/stdlib/bits/stdlib.h b/stdlib/bits/stdlib.h index 067115eeca..ccacbdf76a 100644 --- a/stdlib/bits/stdlib.h +++ b/stdlib/bits/stdlib.h @@ -42,7 +42,7 @@ __NTH (realpath (const char *__restrict __name, char *__restrict __resolved)) return __realpath_alias (__name, __resolved); #if defined _LIBC_LIMITS_H_ && defined PATH_MAX - if (__glibc_unsafe_len (sz, sizeof (char), PATH_MAX)) + if (__glibc_unsafe_len (PATH_MAX, sizeof (char), sz)) return __realpath_chk_warn (__name, __resolved, sz); #endif return __realpath_chk (__name, __resolved, sz);