From: Dan Carpenter Date: Fri, 9 Aug 2024 12:32:30 +0000 (+0300) Subject: selftests/mm: compaction_test: fix off by one in check_compaction() X-Git-Tag: v6.11-rc4~7^2~6 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=af3b7d09a9934220a8136065a0e6985fe0b67a1b;p=thirdparty%2Flinux.git selftests/mm: compaction_test: fix off by one in check_compaction() The "initial_nr_hugepages" variable is unsigned long so it takes up to 20 characters to print, plus 1 more character for the NUL terminator. Unfortunately, this buffer is not quite large enough for the terminator to fit. Also use snprintf() for a belt and suspenders approach. Link: https://lkml.kernel.org/r/87470c06-b45a-4e83-92ff-aac2e7b9c6ba@stanley.mountain Fixes: fb9293b6b015 ("selftests/mm: compaction_test: fix bogus test success and reduce probability of OOM-killer invocation") Signed-off-by: Dan Carpenter Cc: Shuah Khan Signed-off-by: Andrew Morton --- diff --git a/tools/testing/selftests/mm/compaction_test.c b/tools/testing/selftests/mm/compaction_test.c index e140558e6f53f..2c3a0eb6b22d3 100644 --- a/tools/testing/selftests/mm/compaction_test.c +++ b/tools/testing/selftests/mm/compaction_test.c @@ -89,9 +89,10 @@ int check_compaction(unsigned long mem_free, unsigned long hugepage_size, int fd, ret = -1; int compaction_index = 0; char nr_hugepages[20] = {0}; - char init_nr_hugepages[20] = {0}; + char init_nr_hugepages[24] = {0}; - sprintf(init_nr_hugepages, "%lu", initial_nr_hugepages); + snprintf(init_nr_hugepages, sizeof(init_nr_hugepages), + "%lu", initial_nr_hugepages); /* We want to test with 80% of available memory. Else, OOM killer comes in to play */