[merged mm-stable] selftests-mm-pagemap_ioctl-fix-missing-null-checks-after-calloc.patch removed from -mm tree
Andrew Morton <[email protected]>
| Newsgroups | org.kernel.vger.mm-commits |
|---|---|
| Message-ID | <[email protected]> |
The quilt patch titled
Subject: selftests/mm/pagemap_ioctl: fix missing NULL checks after calloc()
has been removed from the -mm tree. Its filename was
selftests-mm-pagemap_ioctl-fix-missing-null-checks-after-calloc.patch
This patch was dropped because it was merged into the mm-stable branch
of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm
------------------------------------------------------
From: longlong yan <[email protected]>
Subject: selftests/mm/pagemap_ioctl: fix missing NULL checks after calloc()
Date: Tue, 21 Jul 2026 14:36:11 +0800
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.
Link: https://lore.kernel.org/[email protected]
Signed-off-by: longlong yan <[email protected]>
Acked-by: David Hildenbrand (Arm) <[email protected]>
Reviewed-by: SJ Park <[email protected]>
Cc: Shuah Khan <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
---
tools/testing/selftests/mm/pagemap_ioctl.c | 8 +++++++-
1 file changed, 7 insertions(+), 1 deletion(-)
--- a/tools/testing/selftests/mm/pagemap_ioctl.c~selftests-mm-pagemap_ioctl-fix-missing-null-checks-after-calloc
+++ a/tools/testing/selftests/mm/pagemap_ioctl.c
@@ -213,6 +213,8 @@ 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);
@@ -700,6 +702,8 @@ int base_tests(char *prefix, char *mem,
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,
@@ -1001,6 +1005,8 @@ 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,
@@ -1163,7 +1169,7 @@ 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);
_
Patches currently in -mm which might be from [email protected] are