Commit-ID: cf9df81b139b6ebaec188d73758f02ca3b2110e4 Gitweb: http://git.kernel.org/tip/cf9df81b139b6ebaec188d73758f02ca3b2110e4 Author: Eric Biggers <[email protected]> AuthorDate: Sun, 24 Sep 2017 12:59:05 +0200 Committer: Ingo Molnar <[email protected]> CommitDate: Tue, 26 Sep 2017 09:43:45 +0200
x86/fpu: Use validate_xstate_header() to validate the xstate_header in xstateregs_set() Tighten the checks in xstateregs_set(). Signed-off-by: Eric Biggers <[email protected]> Cc: Andrew Morton <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Borislav Petkov <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Dmitry Vyukov <[email protected]> Cc: Eric Biggers <[email protected]> Cc: Fenghua Yu <[email protected]> Cc: Kees Cook <[email protected]> Cc: Kevin Hao <[email protected]> Cc: Linus Torvalds <[email protected]> Cc: Michael Halcrow <[email protected]> Cc: Oleg Nesterov <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Rik van Riel <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Wanpeng Li <[email protected]> Cc: Yu-cheng Yu <[email protected]> Cc: [email protected] Link: http://lkml.kernel.org/r/[email protected] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/kernel/fpu/regset.c | 19 ++++++------------- 1 file changed, 6 insertions(+), 13 deletions(-) diff --git a/arch/x86/kernel/fpu/regset.c b/arch/x86/kernel/fpu/regset.c index ee8d2f0..b831d5b 100644 --- a/arch/x86/kernel/fpu/regset.c +++ b/arch/x86/kernel/fpu/regset.c @@ -141,27 +141,20 @@ int xstateregs_set(struct task_struct *target, const struct user_regset *regset, ret = copy_user_to_xstate(xsave, ubuf); } else { ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, xsave, 0, -1); - - /* xcomp_bv must be 0 when using uncompacted format */ - if (!ret && xsave->header.xcomp_bv) - ret = -EINVAL; + if (!ret) + ret = validate_xstate_header(&xsave->header); } /* - * In case of failure, mark all states as init: - */ - if (ret) - fpstate_init(&fpu->state); - - /* * mxcsr reserved bits must be masked to zero for security reasons. */ xsave->i387.mxcsr &= mxcsr_feature_mask; - xsave->header.xfeatures &= xfeatures_mask; + /* - * These bits must be zero. + * In case of failure, mark all states as init: */ - memset(&xsave->header.reserved, 0, 48); + if (ret) + fpstate_init(&fpu->state); return ret; }

