From: "Luis R. Rodriguez" <mcgrof@xxxxxxxxxx> Subject: test_kmod: fix bug which allows negative values on two config options Parsing with kstrtol() enables values to be negative, and we failed to check for negative values when parsing with either test_dev_config_update_uint_sync() or test_dev_config_update_uint_range(). test_dev_config_update_uint_range() has a minimum check though so an issue is not present there. test_dev_config_update_uint_sync() is only used for the number of threads to use (config_num_threads_store()), and indeed this would fail with an attempt for a large allocation. Although the issue is only present in practice with the first fix both by using kstrtoul() instead of kstrtol(). Link: http://lkml.kernel.org/r/20170802211450.27928-4-mcgrof@xxxxxxxxxx Fixes: 39258f448d71 ("kmod: add test driver to stress test the module loader") Signed-off-by: Luis R. Rodriguez <mcgrof@xxxxxxxxxx> Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx> Cc: Colin Ian King <colin.king@xxxxxxxxxxxxx> Cc: David Binderman <dcb314@xxxxxxxxxxx> Cc: Dmitry Torokhov <dmitry.torokhov@xxxxxxxxx> Cc: Eric W. Biederman <ebiederm@xxxxxxxxxxxx> Cc: Jessica Yu <jeyu@xxxxxxxxxx> Cc: Josh Poimboeuf <jpoimboe@xxxxxxxxxx> Cc: Kees Cook <keescook@xxxxxxxxxxxx> Cc: Michal Marek <mmarek@xxxxxxxx> Cc: Miroslav Benes <mbenes@xxxxxxx> Cc: Petr Mladek <pmladek@xxxxxxxx> Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx> Cc: Shuah Khan <shuah@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- lib/test_kmod.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff -puN lib/test_kmod.c~test_kmod-fix-bug-which-allows-negative-values-on-two-config-options lib/test_kmod.c --- a/lib/test_kmod.c~test_kmod-fix-bug-which-allows-negative-values-on-two-config-options +++ a/lib/test_kmod.c @@ -880,10 +880,10 @@ static int test_dev_config_update_uint_s int (*test_sync)(struct kmod_test_device *test_dev)) { int ret; - long new; + unsigned long new; unsigned int old_val; - ret = kstrtol(buf, 10, &new); + ret = kstrtoul(buf, 10, &new); if (ret) return ret; @@ -918,9 +918,9 @@ static int test_dev_config_update_uint_r unsigned int max) { int ret; - long new; + unsigned long new; - ret = kstrtol(buf, 10, &new); + ret = kstrtoul(buf, 10, &new); if (ret) return ret; _ -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
