On 7/21/26 08:36, longlong yan wrote: > The pagemap_ioctl selftest allocates memory via calloc() in several > places but does not check the return values. If calloc() fails, the > subsequent code will dereference a NULL pointer and crash. > > Additionally, in sanity_tests(), the calloc() failure check incorrectly > uses MAP_FAILED (the mmap() error constant) instead of NULL. Since > calloc() returns NULL on failure, the check never triggers and a > failed allocation goes undetected. > > Add NULL checks after each calloc() call, and fix the wrong error > constant in sanity_tests(). Use ksft_exit_fail_msg() consistent with > the existing error handling pattern in the file. > > Signed-off-by: longlong yan <[email protected]> > --- > tools/testing/selftests/mm/pagemap_ioctl.c | 8 +++++++- > 1 file changed, 7 insertions(+), 1 deletion(-) > > diff --git a/tools/testing/selftests/mm/pagemap_ioctl.c > b/tools/testing/selftests/mm/pagemap_ioctl.c > index f9bcff8e78fa..f6629f44a13d 100644 > --- a/tools/testing/selftests/mm/pagemap_ioctl.c > +++ b/tools/testing/selftests/mm/pagemap_ioctl.c > @@ -212,6 +212,8 @@ int userfaultfd_tests(void) > > vec_size = mem_size/page_size; > vec = calloc(vec_size, sizeof(struct page_region)); > + if (!vec) > + ksft_exit_fail_msg("error nomem\n"); > > written = pagemap_ioctl(mem, mem_size, vec, 1, PM_SCAN_WP_MATCHING | > PM_SCAN_CHECK_WPASYNC, > vec_size - 2, PAGE_IS_WRITTEN, 0, 0, > PAGE_IS_WRITTEN); > @@ -699,6 +701,8 @@ int base_tests(char *prefix, char *mem, unsigned long > long mem_size, int skip) > vec_size = mem_size/page_size; > vec = calloc(vec_size, sizeof(struct page_region)); > vec2 = calloc(vec_size, sizeof(struct page_region)); > + if (!vec || !vec2) > + ksft_exit_fail_msg("error nomem\n"); > > /* 1. all new pages must be not be written (dirty) */ > written = pagemap_ioctl(mem, mem_size, vec, 1, PM_SCAN_WP_MATCHING | > PM_SCAN_CHECK_WPASYNC, > @@ -1000,6 +1004,8 @@ int unmapped_region_tests(void) > int written, len = 0x00040000; > long vec_size = len / page_size; > struct page_region *vec = calloc(vec_size, sizeof(struct page_region)); > + if (!vec) > + ksft_exit_fail_msg("error nomem\n"); > > /* 1. Get written pages */ > written = pagemap_ioctl(start, len, vec, vec_size, 0, 0, > @@ -1116,7 +1122,7 @@ int sanity_tests(void) > > vec = calloc(vec_size, sizeof(struct page_region)); > mem = mmap(NULL, mem_size, PROT_READ | PROT_WRITE, MAP_PRIVATE | > MAP_ANON, -1, 0); > - if (mem == MAP_FAILED || vec == MAP_FAILED) > + if (mem == MAP_FAILED || !vec) > ksft_exit_fail_msg("error nomem\n"); > > wp_init(mem, mem_size);
Acked-by: David Hildenbrand (Arm) <[email protected]> -- Cheers, David
