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, 25 Sep 2017 21:56:00 +0200 (CEST) From: Thomas Gleixner <tglx@...utronix.de> To: Ingo Molnar <mingo@...nel.org> cc: linux-kernel@...r.kernel.org, Andrew Morton <akpm@...ux-foundation.org>, Eric Biggers <ebiggers3@...il.com>, Andy Lutomirski <luto@...capital.net>, Borislav Petkov <bp@...en8.de>, Dave Hansen <dave.hansen@...ux.intel.com>, Fenghua Yu <fenghua.yu@...el.com>, "H . Peter Anvin" <hpa@...or.com>, Linus Torvalds <torvalds@...ux-foundation.org>, Oleg Nesterov <oleg@...hat.com>, Peter Zijlstra <peterz@...radead.org>, Rik van Riel <riel@...hat.com>, Yu-cheng Yu <yu-cheng.yu@...el.com> Subject: Re: [PATCH 08/33] x86/fpu: Clarify parameter names in the copy_xstate_to_*() methods On Sat, 23 Sep 2017, Ingo Molnar wrote: > static inline int > __copy_xstate_to_kernel(void *kbuf, > const void *data, > - unsigned int pos, unsigned int count, int end_pos) > + unsigned int offset, unsigned int size, int size_total) Why is size_total int? > { > - if (!count) > + if (!size) > return 0; > > - if (end_pos < 0 || pos < end_pos) { > - unsigned int copy = end_pos < 0 ? count : min(count, end_pos - pos); > + if (size_total < 0 || offset < size_total) { And why would it be < 0? The call sites of this inline are all inside of: int copy_xstate_to_kernel(void *kbuf, struct xregs_state *xsave, unsigned int offset_start, int size_total) and hand in size_total completely unmodified. copy_xstate_to_kernel() itself has a single callsite: int xstateregs_get(struct task_struct *target, const struct user_regset *regset, unsigned int pos, unsigned int count, void *kbuf, void __user *ubuf) and that hands in count unmodified. The same issue is with the to_user() variant which is even more obvious. All callers are inside of copy_xstate_to_user() where size_total is an unsigned int argument which is handed in unmodified. This signed/unsigned mismatch is confusing at best. Thanks, tglx
Powered by blists - more mailing lists