From ed318beab986c6f6ccf2507d4753dfea6a7b1f8d Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Wed, 1 Nov 2023 09:56:06 -0300 Subject: [PATCH] support: Add support_set_vma_name Check if kernel supports prctl (PR_SET_VMA, PR_SET_VMA_ANON_NAME, ...). Reviewed-by: DJ Delorie --- support/Makefile | 1 + support/support.h | 4 +++ support/support_set_vma_name_supported.c | 49 ++++++++++++++++++++++++++++++++ 3 files changed, 54 insertions(+) create mode 100644 support/support_set_vma_name_supported.c diff --git a/support/Makefile b/support/Makefile index 917a858bd1..9aa7f23a6e 100644 --- a/support/Makefile +++ b/support/Makefile @@ -80,6 +80,7 @@ libsupport-routines = \ support_select_modifies_timeout \ support_select_normalizes_timeout \ support_set_small_thread_stack_size \ + support_set_vma_name_supported \ support_shared_allocate \ support_small_stack_thread_attribute \ support_socket_so_timestamp_time64 \ diff --git a/support/support.h b/support/support.h index b7f76bf080..4a068d3aee 100644 --- a/support/support.h +++ b/support/support.h @@ -235,6 +235,10 @@ void support_stack_free (struct support_stack *stack); The returned value is the lowest file descriptor number. */ int support_open_dev_null_range (int num, int flags, mode_t mode); + +/* Check if kernel supports set VMA range name. */ +extern bool support_set_vma_name_supported (void); + __END_DECLS #endif /* SUPPORT_H */ diff --git a/support/support_set_vma_name_supported.c b/support/support_set_vma_name_supported.c new file mode 100644 index 0000000000..712caa9b9b --- /dev/null +++ b/support/support_set_vma_name_supported.c @@ -0,0 +1,49 @@ +/* Check if kernel supports set VMA range name. + Copyright (C) 2023 Free Software Foundation, Inc. + 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 +#ifdef __linux__ +# include +#endif + +bool +support_set_vma_name_supported (void) +{ +#ifdef __linux__ + size_t size = sysconf (_SC_PAGESIZE); + if (size == -1) + FAIL_EXIT1 ("sysconf (_SC_PAGESIZE): %m\n"); + + void *vma = xmmap (0, + size, + PROT_NONE, + MAP_PRIVATE|MAP_ANONYMOUS|MAP_NORESERVE, + -1); + + int r = prctl (PR_SET_VMA, PR_SET_VMA_ANON_NAME, vma, size, "vmaname"); + + xmunmap (vma, size); + + return r == 0; +#else + return false; +#endif +} -- 2.11.4.GIT