[PATCH 5.13 107/351] powerpc/inst: Fix sparse detection on get_user_instr()

Greg Kroah-Hartman
2021-07-19T17:26:24Z

From: Christophe Leroy <christophe.leroy@csgroup.eu>

[ Upstream commit b3a9e523237013477bea914b7fbfbe420428b988 ]

get_user_instr() lacks sparse detection for the __user tag.

This is because __gui_ptr is assigned with a cast.

Fix that by adding a __chk_user_ptr()

Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/0320e5b41a794fd456ab8c5993bbfadcf9e1d8b4.1621516826.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/powerpc/include/asm/inst.h | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/include/asm/inst.h b/arch/powerpc/include/asm/inst.h
index 268d3bd073c8..887ef150fdda 100644
--- a/arch/powerpc/include/asm/inst.h
+++ b/arch/powerpc/include/asm/inst.h
@@ -12,6 +12,8 @@
unsigned long __gui_ptr = (unsigned long)ptr; \
struct ppc_inst __gui_inst; \
unsigned int __prefix, __suffix; \
+ \
+ __chk_user_ptr(ptr); \
__gui_ret = gu_op(__prefix, (unsigned int __user *)__gui_ptr); \
if (__gui_ret == 0) { \
if ((__prefix >> 26) == OP_PREFIX) { \
@@ -29,7 +31,10 @@
})
#else /* !CONFIG_PPC64 */
#define ___get_user_instr(gu_op, dest, ptr) \
- gu_op((dest).val, (u32 __user *)(ptr))
+({ \
+ __chk_user_ptr(ptr); \
+ gu_op((dest).val, (u32 __user *)(ptr)); \
+})
#endif /* CONFIG_PPC64 */

#define get_user_instr(x, ptr) \
--
2.30.2