diff options
Diffstat (limited to 'arch/x86/kernel/fpu/xstate.h')
| -rw-r--r-- | arch/x86/kernel/fpu/xstate.h | 27 |
1 files changed, 26 insertions, 1 deletions
diff --git a/arch/x86/kernel/fpu/xstate.h b/arch/x86/kernel/fpu/xstate.h index 0b86a5002c84..aa16f1a1bbcf 100644 --- a/arch/x86/kernel/fpu/xstate.h +++ b/arch/x86/kernel/fpu/xstate.h @@ -69,6 +69,28 @@ static inline u64 xfeatures_mask_independent(void) return fpu_kernel_cfg.independent_features; } +/* + * Update the value of PKRU register that was already pushed onto the signal frame. + */ +static inline int update_pkru_in_sigframe(struct xregs_state __user *buf, u64 mask, u32 pkru) +{ + u64 xstate_bv; + int err; + + if (unlikely(!cpu_feature_enabled(X86_FEATURE_OSPKE))) + return 0; + + /* Mark PKRU as in-use so that it is restored correctly. */ + xstate_bv = (mask & xfeatures_in_use()) | XFEATURE_MASK_PKRU; + + err = __put_user(xstate_bv, &buf->header.xfeatures); + if (err) + return err; + + /* Update PKRU value in the userspace xsave buffer. */ + return __put_user(pkru, (unsigned int __user *)get_xsave_addr_user(buf, XFEATURE_PKRU)); +} + /* XSAVE/XRSTOR wrapper functions */ #ifdef CONFIG_X86_64 @@ -256,7 +278,7 @@ static inline u64 xfeatures_need_sigframe_write(void) * The caller has to zero buf::header before calling this because XSAVE* * does not touch the reserved fields in the header. */ -static inline int xsave_to_user_sigframe(struct xregs_state __user *buf) +static inline int xsave_to_user_sigframe(struct xregs_state __user *buf, u32 pkru) { /* * Include the features which are not xsaved/rstored by the kernel @@ -281,6 +303,9 @@ static inline int xsave_to_user_sigframe(struct xregs_state __user *buf) XSTATE_OP(XSAVE, buf, lmask, hmask, err); clac(); + if (!err) + err = update_pkru_in_sigframe(buf, mask, pkru); + return err; } |