Commit af95774b authored by Eric Biggers's avatar Eric Biggers Committed by Ingo Molnar

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: default avatarEric 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.orgSigned-off-by: default avatarIngo Molnar <mingo@kernel.org>
parent b89eda48
...@@ -1138,15 +1138,12 @@ int copy_xstate_to_user(void __user *ubuf, struct xregs_state *xsave, unsigned i ...@@ -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 * 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 * and copy to the target thread. This is called from xstateregs_set().
* there we check the CPU has XSAVES and a whole standard-sized buffer
* exists.
*/ */
int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf) int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
{ {
unsigned int offset, size; unsigned int offset, size;
int i; int i;
u64 allowed_features;
struct xstate_header hdr; struct xstate_header hdr;
offset = offsetof(struct xregs_state, header); offset = offsetof(struct xregs_state, header);
...@@ -1154,12 +1151,7 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf) ...@@ -1154,12 +1151,7 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf)
memcpy(&hdr, kbuf + offset, size); memcpy(&hdr, kbuf + offset, size);
/* if (validate_xstate_header(&hdr))
* Reject if the user sets any disabled or supervisor features:
*/
allowed_features = xfeatures_mask & ~XFEATURE_MASK_SUPERVISOR;
if (hdr.xfeatures & ~allowed_features)
return -EINVAL; return -EINVAL;
for (i = 0; i < XFEATURE_MAX; i++) { for (i = 0; i < XFEATURE_MAX; i++) {
......
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