From 507f55c05f30c9eb80faf2546ec635c338c039eb Mon Sep 17 00:00:00 2001 From: Florian Weimer Date: Fri, 28 Jun 2019 10:48:48 +0200 Subject: [PATCH] Linux: Use mmap instead of malloc in dirent/tst-getdents64 malloc dirties the entire allocated memory region due to M_PERTURB in the test harness. --- ChangeLog | 6 ++++++ sysdeps/unix/sysv/linux/tst-getdents64.c | 12 +++++++++--- 2 files changed, 15 insertions(+), 3 deletions(-) diff --git a/ChangeLog b/ChangeLog index e1d6327..65129ff 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2019-06-28 Florian Weimer + + * sysdeps/unix/sysv/linux/tst-getdents64.c (large_buffer_checks): + Use mmap instead of malloc. malloc with M_PERTURB writes to the + entire allocated memory range. + 2019-06-28 Tobias Klauser * sysdeps/unix/sysv/linux/dl-vdso.h (PREPARE_VERSION): Remove macro. diff --git a/sysdeps/unix/sysv/linux/tst-getdents64.c b/sysdeps/unix/sysv/linux/tst-getdents64.c index 24e77e0..8a28e6c 100644 --- a/sysdeps/unix/sysv/linux/tst-getdents64.c +++ b/sysdeps/unix/sysv/linux/tst-getdents64.c @@ -27,6 +27,7 @@ #include #include #include +#include #include /* Called by large_buffer_checks below. */ @@ -53,8 +54,13 @@ large_buffer_checks (int fd) size_t large_buffer_size; if (!__builtin_add_overflow (UINT_MAX, 2, &large_buffer_size)) { - char *large_buffer = malloc (large_buffer_size); - if (large_buffer == NULL) + int flags = MAP_ANONYMOUS | MAP_PRIVATE; +#ifdef MAP_NORESERVE + flags |= MAP_NORESERVE; +#endif + void *large_buffer = mmap (NULL, large_buffer_size, + PROT_READ | PROT_WRITE, flags, -1, 0); + if (large_buffer == MAP_FAILED) printf ("warning: could not allocate %zu bytes of memory," " subtests skipped\n", large_buffer_size); else @@ -65,8 +71,8 @@ large_buffer_checks (int fd) large_buffer_check (fd, large_buffer, UINT_MAX); large_buffer_check (fd, large_buffer, (size_t) UINT_MAX + 1); large_buffer_check (fd, large_buffer, (size_t) UINT_MAX + 2); + xmunmap (large_buffer, large_buffer_size); } - free (large_buffer); } } -- 2.7.4