Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1579933

RE: [PATCH V5 3/4] Move stack parameters for sed_ioctl to prevent oversized stack with CONFIG_KASAN

Show all headers | View raw

From: Scott Bauer Sent: 13 February 2017 16:11
> When CONFIG_KASAN is enabled, compilation fails:
> 
> block/sed-opal.c: In function 'sed_ioctl':
> block/sed-opal.c:2447:1: error: the frame size of 2256 bytes is larger than 2048 bytes [-Werror=frame-
> larger-than=]
> 
> Moved all the ioctl structures off the stack and dynamically activate
> using _IOC_SIZE()

Think I'd not that this simplifies the code considerably.
AFAICT CONFIG_KASAN is a just brainf*ck.
It at least needs annotation that copy_from_user() has properties
similar to memset().
So if the size matches that of the type then no guard space (etc)
is required.

...
> +	ioctl_ptr = memdup_user(arg,  _IOC_SIZE(cmd));
> +	if (IS_ERR_OR_NULL(ioctl_ptr)) {
> +		ret = PTR_ERR(ioctl_ptr);
> +		goto out;
...
> + out:
> +	kfree(ioctl_ptr);
> +	return ret;
>  }

That error path doesn't look quite right to me.

	David

Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

SED Opal Fixups Scott Bauer <scott.bauer@intel.com> - 2017-02-13 17:30 +0100
  [PATCH V5 4/4] Maintainers: Modify SED list from nvme to block Scott Bauer <scott.bauer@intel.com> - 2017-02-13 17:30 +0100
    Re: [PATCH V5 4/4] Maintainers: Modify SED list from nvme to block Christoph Hellwig <hch@infradead.org> - 2017-02-14 09:20 +0100
  Re: [PATCH V5 1/4] block: sed-opal: change ioctl to take user  pointer instead of unsinged long Scott Bauer <scott.bauer@intel.com> - 2017-02-13 17:30 +0100
    Re: [PATCH V5 1/4] block: sed-opal: change ioctl to take user  pointer instead of unsinged long Christoph Hellwig <hch@infradead.org> - 2017-02-14 09:20 +0100
  [PATCH V5 1/4] block: sed-opal: change ioctl to take user pointer instead of unsinged long Scott Bauer <scott.bauer@intel.com> - 2017-02-13 17:30 +0100
  [PATCH V5 3/4] Move stack parameters for sed_ioctl to prevent oversized stack with CONFIG_KASAN Scott Bauer <scott.bauer@intel.com> - 2017-02-13 17:30 +0100
    RE: [PATCH V5 3/4] Move stack parameters for sed_ioctl to prevent  oversized stack with CONFIG_KASAN David Laight <David.Laight@ACULAB.COM> - 2017-02-13 17:40 +0100
      Re: [PATCH V5 3/4] Move stack parameters for sed_ioctl to prevent  oversized stack with CONFIG_KASAN Scott Bauer <scott.bauer@intel.com> - 2017-02-13 17:40 +0100
        Re: [PATCH V5 3/4] Move stack parameters for sed_ioctl to prevent  oversized stack with CONFIG_KASAN Arnd Bergmann <arnd@arndb.de> - 2017-02-13 18:10 +0100
          RE: [PATCH V5 3/4] Move stack parameters for sed_ioctl to prevent  oversized stack with CONFIG_KASAN David Laight <David.Laight@ACULAB.COM> - 2017-02-13 18:10 +0100
            Re: [PATCH V5 3/4] Move stack parameters for sed_ioctl to prevent  oversized stack with CONFIG_KASAN Arnd Bergmann <arnd@arndb.de> - 2017-02-13 21:20 +0100
  [PATCH V5 2/4] uapi: sed-opal fix IOW for activate lsp to use correct struct Scott Bauer <scott.bauer@intel.com> - 2017-02-13 17:30 +0100
    Re: [PATCH V5 2/4] uapi: sed-opal fix IOW for activate lsp to use  correct struct Christoph Hellwig <hch@infradead.org> - 2017-02-14 09:20 +0100

csiph-web