x86/fpu/signal: Fix missed conversion to correct boolean retval in save_xstate_epilog()

mainline inclusion
from mainline-v5.16-rc1
commit 724fc024
category: feature
bugzilla: https://gitee.com/openeuler/intel-kernel/issues/I590ZC
CVE: NA

Intel-SIG: commit 724fc024 x86/fpu/signal: Fix missed conversion.

--------------------------------

Fix the missing return code polarity in save_xstate_epilog().

 [ bp: Massage, use the right commit in the Fixes: tag ]

Fixes: 2af07f3a ("x86/fpu/signal: Change return type of copy_fpregs_to_sigframe() helpers to boolean")
Reported-by: NRemi Duraffort <remi.duraffort@linaro.org>
Signed-off-by: NAnders Roxell <anders.roxell@linaro.org>
Signed-off-by: NBorislav Petkov <bp@suse.de>
Tested-by: NNick Desaulniers <ndesaulniers@google.com>
Link: https://github.com/ClangBuiltLinux/linux/issues/1461
Link: https://lkml.kernel.org/r/20210922200901.1823741-1-anders.roxell@linaro.orgSigned-off-by: NLin Wang <lin.x.wang@intel.com>
Signed-off-by: NAichun Shi <aichun.shi@intel.com>

arch/x86/kernel/fpu/signal.c

@@ -106,7 +106,7 @@ static inline bool save_xstate_epilog(void __user *buf, int ia32_frame)
 	err = __copy_to_user(&x->i387.sw_reserved, sw_bytes, sizeof(*sw_bytes));
 
 	if (!use_xsave())
-		return err;
+		return !err;
 
 	err |= __put_user(FP_XSTATE_MAGIC2,
 			  (__u32 __user *)(buf + fpu_user_xstate_size));