From: Eric Biggers <[email protected]> We have this information in the xstate_header.
Signed-off-by: Eric Biggers <[email protected]> Cc: Andy Lutomirski <[email protected]> Cc: Dave Hansen <[email protected]> Cc: Dmitry Vyukov <[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] Signed-off-by: Ingo Molnar <[email protected]> --- arch/x86/kernel/fpu/xstate.c | 10 ++++------ 1 file changed, 4 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 02591b96bb25..c97c4a9db52a 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -1146,7 +1146,6 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf) { unsigned int offset, size; int i; - u64 xfeatures; u64 allowed_features; struct xstate_header hdr; @@ -1154,20 +1153,19 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf) size = sizeof(hdr); memcpy(&hdr, kbuf + offset, size); - xfeatures = hdr.xfeatures; /* * Reject if the user sets any disabled or supervisor features: */ allowed_features = xfeatures_mask & ~XFEATURE_MASK_SUPERVISOR; - if (xfeatures & ~allowed_features) + if (hdr.xfeatures & ~allowed_features) return -EINVAL; for (i = 0; i < XFEATURE_MAX; i++) { u64 mask = ((u64)1 << i); - if (xfeatures & mask) { + if (hdr.xfeatures & mask) { void *dst = __raw_xsave_addr(xsave, 1 << i); offset = xstate_offsets[i]; @@ -1177,7 +1175,7 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf) } } - if (xfeatures_mxcsr_quirk(xfeatures)) { + if (xfeatures_mxcsr_quirk(hdr.xfeatures)) { offset = offsetof(struct fxregs_state, mxcsr); size = MXCSR_AND_FLAGS_SIZE; memcpy(&xsave->i387.mxcsr, kbuf + offset, size); @@ -1192,7 +1190,7 @@ int copy_kernel_to_xstate(struct xregs_state *xsave, const void *kbuf) /* * Add back in the features that came in from userspace: */ - xsave->header.xfeatures |= xfeatures; + xsave->header.xfeatures |= hdr.xfeatures; return 0; } -- 2.11.0
