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authorEric Biggers <ebiggers@google.com>2017-09-24 13:59:09 +0300
committerIngo Molnar <mingo@kernel.org>2017-09-26 10:43:47 +0300
commitaf95774b3ca080b0e1e651c0fc7680f3444ddda7 (patch)
treea8a9cb7a3f2da05c49c08a7335c1f051076d879b /arch/x86/kernel/fpu
parentb89eda482d7849a1c146b6d0a42f4e76369bb08e (diff)
downloadlinux-af95774b3ca080b0e1e651c0fc7680f3444ddda7.tar.xz
x86/fpu: Use validate_xstate_header() to validate the xstate_header in copy_kernel_to_xstate()
Tighten the checks in copy_kernel_to_xstate(). Signed-off-by: Eric Biggers <ebiggers@google.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Dave Hansen <dave.hansen@linux.intel.com> Cc: Dmitry Vyukov <dvyukov@google.com> Cc: Eric Biggers <ebiggers3@gmail.com> Cc: Fenghua Yu <fenghua.yu@intel.com> Cc: Kees Cook <keescook@chromium.org> Cc: Kevin Hao <haokexin@gmail.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Michael Halcrow <mhalcrow@google.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Rik van Riel <riel@redhat.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Wanpeng Li <wanpeng.li@hotmail.com> Cc: Yu-cheng Yu <yu-cheng.yu@intel.com> Cc: kernel-hardening@lists.openwall.com Link: http://lkml.kernel.org/r/20170924105913.9157-7-mingo@kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'arch/x86/kernel/fpu')
-rw-r--r--arch/x86/kernel/fpu/xstate.c12
1 files changed, 2 insertions, 10 deletions
diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c
index c97c4a9db52a..325db7850335 100644
--- a/arch/x86/kernel/fpu/xstate.c
+++ b/arch/x86/kernel/fpu/xstate.c
@@ -1138,15 +1138,12 @@ int copy_xstate_to_user(void __user *ubuf, struct xregs_state *xsave, unsigned i
/*
* Convert from a ptrace standard-format kernel buffer to kernel XSAVES format
- * and copy to the target thread. This is called from xstateregs_set() and
- * there we check the CPU has XSAVES and a whole standard-sized buffer
- * exists.
+ * and copy to the target thread. This is called from xstateregs_set().
*/
int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
{
unsigned int offset, size;
int i;
- u64 allowed_features;
struct xstate_header hdr;
offset = offsetof(struct xregs_state, header);
@@ -1154,12 +1151,7 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
memcpy(&hdr, kbuf + offset, size);
- /*
- * Reject if the user sets any disabled or supervisor features:
- */
- allowed_features = xfeatures_mask & ~XFEATURE_MASK_SUPERVISOR;
-
- if (hdr.xfeatures & ~allowed_features)
+ if (validate_xstate_header(&hdr))
return -EINVAL;
for (i = 0; i < XFEATURE_MAX; i++) {