From 2e9fb9953df91ef6310da22182ca8f4496907502 Mon Sep 17 00:00:00 2001 From: Rusty Russell Date: Wed, 11 Aug 2010 23:04:10 -0600 Subject: params: don't hand NULL values to param.set callbacks. MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit An audit by Dongdong Deng revealed that most driver-author-written param calls don't handle val == NULL (which happens when parameters are specified with no =, eg "foo" instead of "foo=1"). The only real case to use this is boolean, so handle it specially for that case and remove a source of bugs for everyone else. Signed-off-by: Rusty Russell Cc: Dongdong Deng Cc: Américo Wang --- kernel/params.c | 20 +++----------------- 1 file changed, 3 insertions(+), 17 deletions(-) (limited to 'kernel') diff --git a/kernel/params.c b/kernel/params.c index 0b30ecd53a52..3c4a9f1b095e 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -58,6 +58,9 @@ static int parse_one(char *param, /* Find parameter */ for (i = 0; i < num_params; i++) { if (parameq(param, params[i].name)) { + /* Noone handled NULL, so do it here. */ + if (!val && params[i].set != param_set_bool) + return -EINVAL; DEBUGP("They are equal! Calling %p\n", params[i].set); return params[i].set(val, ¶ms[i]); @@ -181,7 +184,6 @@ int parse_args(const char *name, tmptype l; \ int ret; \ \ - if (!val) return -EINVAL; \ ret = strtolfn(val, 0, &l); \ if (ret == -EINVAL || ((type)l != l)) \ return -EINVAL; \ @@ -203,12 +205,6 @@ STANDARD_PARAM_DEF(ulong, unsigned long, "%lu", unsigned long, strict_strtoul); int param_set_charp(const char *val, struct kernel_param *kp) { - if (!val) { - printk(KERN_ERR "%s: string parameter expected\n", - kp->name); - return -EINVAL; - } - if (strlen(val) > 1024) { printk(KERN_ERR "%s: string parameter too long\n", kp->name); @@ -309,12 +305,6 @@ static int param_array(const char *name, kp.arg = elem; kp.flags = flags; - /* No equals sign? */ - if (!val) { - printk(KERN_ERR "%s: expects arguments\n", name); - return -EINVAL; - } - *num = 0; /* We expect a comma-separated list of values. */ do { @@ -381,10 +371,6 @@ int param_set_copystring(const char *val, struct kernel_param *kp) { const struct kparam_string *kps = kp->str; - if (!val) { - printk(KERN_ERR "%s: missing param set value\n", kp->name); - return -EINVAL; - } if (strlen(val)+1 > kps->maxlen) { printk(KERN_ERR "%s: string doesn't fit in %u chars.\n", kp->name, kps->maxlen-1); -- cgit v1.2.3