lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Mon, 22 Feb 2010 19:41:21 +1030 From: Rusty Russell <rusty@...tcorp.com.au> To: Américo Wang <xiyou.wangcong@...il.com> Cc: Dongdong Deng <dongdong.deng@...driver.com>, davem@...emloft.net, linux-kernel@...r.kernel.org, netdev@...r.kernel.org, jason.wessel@...driver.com, lenb@...nel.org, dwmw2@...radead.org, mdharm-usb@...-eyed-alien.net, bfields@...ldses.org, robert.richter@....com Subject: Re: [PATCH] module param_call: fix potential NULL pointer dereference On Sun, 21 Feb 2010 07:11:36 pm Américo Wang wrote: > On Sun, Feb 21, 2010 at 3:24 PM, Dongdong Deng > <dongdong.deng@...driver.com> wrote: > > The param_set_fn() function will get a parameter which is a NULL > > pointer when insmod module with params via following method: > > > > $insmod module.ko module_params > > > > BTW: the normal method usually as following format: > > $insmod module.ko module_params=example > > > > If the param_set_fn() function didn't check that parameter and used > > it directly, it could caused an OOPS due to NULL pointer dereference. > > > > The solution is simple: > > Just checking the parameter before using in param_set_fn(). > > > > Example: > > int set_module_params(const char *val, struct kernel_param *kp) > > { > > /*Checking the val parameter before using */ > > if (!val) > > return -EINVAL; > > ... > > } > > module_param_call(module_params, set_module_params, NULL, NULL, 0644); > > > > Why not just checking all of them in the generic code? It seemed useful to allow 'foo' as well as 'foo='. But given these examples, obviously that was too easy to misuse. So I like your patch; please annotate it properly and put a comment like: /* We used to hand NULL for bare params, but most code didn't handle it :( */ I assume none of those non-standard param parsers *want* to handle NULL? Thanks, Rusty. -- Away travelling 25Feb-26Mar (6 .de + 1 .pl + 17 .lt + 2 .sg) -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
Powered by blists - more mailing lists