Messages in this thread | | | Subject | Re: [x86] copy_from{to}_user question | From | yalin wang <> | Date | Mon, 17 Aug 2015 11:27:01 +0800 |
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> On Aug 14, 2015, at 00:43, Borislav Petkov <bp@suse.de> wrote: > > On Thu, Aug 13, 2015 at 06:04:54PM +0800, yalin wang wrote: >> we store type into one fix register, for example r12 , >> then in fix up code, we can know the exception is caused by copy_from >> copy_to or copy_in user function by check r12 value(0 , 1 ,2 value), then if >> it is copy_from, we only allow read fault, if the exception is write fault, panic() . >> >> the same rules also apply to copy_to / copy_in function . >> >> is it possible to change it like this ? > > ... and we'll do all that jumping through hoops to fix what actual, > real-life problem exactly? i just want the x86 copy_from{to,in}_user() function have the same behaviour as other platforms. and can disclose potential BUGs in kernel, if do like this.
Thanks.
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