In save_xstate_epilog(), use __user when type-casting userspace pointers.
In setup_sigcontext() and x32_setup_rt_frame(), cast the userspace
pointers to 'unsigned long __user *' before writing into them.
These pointers are originally '__u32 __user *' or '__u64 __user *',
causing sparse to complain when a userspace pointer is written into
them. The casts are okay because the pointers always point to
pointer-sized values.
Thanks to Luc Van Oostenryck and Al Viro for explaining this to me.
Signed-off-by: Jann Horn <ja...@google.com>
---
arch/x86/kernel/fpu/signal.c | 6 +++---
arch/x86/kernel/signal.c | 4 ++--
2 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kernel/fpu/signal.c b/arch/x86/kernel/fpu/signal.c
index f6a1d299627c..55b80de13ea5 100644
--- a/arch/x86/kernel/fpu/signal.c
+++ b/arch/x86/kernel/fpu/signal.c
@@ -92,13 +92,13 @@ static inline int save_xstate_epilog(void __user *buf, int
ia32_frame)
return err;
err |= __put_user(FP_XSTATE_MAGIC2,
- (__u32 *)(buf + fpu_user_xstate_size));
+ (__u32 __user *)(buf + fpu_user_xstate_size));
/*
* Read the xfeatures which we copied (directly from the cpu or
* from the state in task struct) to the user buffers.
*/
- err |= __get_user(xfeatures, (__u32 *)&x->header.xfeatures);
+ err |= __get_user(xfeatures, (__u32 __user *)&x->header.xfeatures);
/*
* For legacy compatible, we always set FP/SSE bits in the bit
@@ -113,7 +113,7 @@ static inline int save_xstate_epilog(void __user *buf, int
ia32_frame)
*/
xfeatures |= XFEATURE_MASK_FPSSE;
- err |= __put_user(xfeatures, (__u32 *)&x->header.xfeatures);
+ err |= __put_user(xfeatures, (__u32 __user *)&x->header.xfeatures);
return err;
}
diff --git a/arch/x86/kernel/signal.c b/arch/x86/kernel/signal.c
index 08dfd4c1a4f9..b419e1a1a0ce 100644
--- a/arch/x86/kernel/signal.c
+++ b/arch/x86/kernel/signal.c
@@ -206,7 +206,7 @@ int setup_sigcontext(struct sigcontext __user *sc, void
__user *fpstate,
put_user_ex(regs->ss, &sc->ss);
#endif /* CONFIG_X86_32 */
- put_user_ex(fpstate, &sc->fpstate);
+ put_user_ex(fpstate, (unsigned long __user *)&sc->fpstate);
/* non-iBCS2 extensions.. */
put_user_ex(mask, &sc->oldmask);
@@ -569,7 +569,7 @@ static int x32_setup_rt_frame(struct ksignal *ksig,
restorer = NULL;
err |= -EFAULT;
}
- put_user_ex(restorer, &frame->pretcode);
+ put_user_ex(restorer, (unsigned long __user *)&frame->pretcode);
} put_user_catch(err);
err |= setup_sigcontext(&frame->uc.uc_mcontext, fpstate,
--
2.21.0.392.gf8f6787159e-goog
