From: Thomas Gleixner Date: Thu, 24 Jun 2021 15:09:18 +0000 (+0200) Subject: x86/fpu/xstate: Clear xstate header in copy_xstate_to_uabi_buf() again X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=93c2cdc975aab53c222472c5b96c2d41dbeb350c;p=linux.git x86/fpu/xstate: Clear xstate header in copy_xstate_to_uabi_buf() again The change which made copy_xstate_to_uabi_buf() usable for [x]fpregs_get() removed the zeroing of the header which means the header, which is copied to user space later, contains except for the xfeatures member, random stack content. Add the memset() back to zero it before usage. Fixes: eb6f51723f03 ("x86/fpu: Make copy_xstate_to_kernel() usable for [x]fpregs_get()") Reported-by: kernel test robot Signed-off-by: Thomas Gleixner Signed-off-by: Borislav Petkov Link: https://lkml.kernel.org/r/875yy3wb8h.ffs@nanos.tec.linutronix.de --- diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index 21a10a66c4e45..c8def1b7f8fba 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -982,6 +982,7 @@ void copy_xstate_to_uabi_buf(struct membuf to, struct task_struct *tsk, unsigned int zerofrom; int i; + memset(&header, 0, sizeof(header)); header.xfeatures = xsave->header.xfeatures; /* Mask out the feature bits depending on copy mode */