Hello,
this series fixes return value, out-of-bound stack access and value
truncation in xtensa implementation of {get,put}_user() for 64bit
values. It also cleans up naming of assembly parameters in
__{get,put}_user_asm and __check_align_{1,2,4}.
Changes v2->v3:
- fix assembly argument constraint for error code
- rearrange result zero-initialization for error paths in __get_user_asm
Changes v1->v2:
- initialize result when access_ok check fails in __get_user_check
- initialize result in __get_user_asm for unaligned access
Al Viro (1):
xtensa: fix {get,put}_user() for 64bit values
Max Filippov (2):
xtensa: clean up assembly arguments in uaccess macros
xtensa: fix type conversion in __get_user_[no]check
arch/xtensa/include/asm/uaccess.h | 94 +++++++++++++++++--------------
1 file changed, 53 insertions(+), 41 deletions(-)
--
2.20.1
Numeric assembly arguments are hard to understand and assembly code that
uses them is hard to modify. Use named arguments in __check_align_*,
__get_user_asm and __put_user_asm. Modify macro parameter names so that
they don't affect argument names. Use '+' constraint for the [err]
argument instead of having it as both input and output.
Signed-off-by: Max Filippov <[email protected]>
---
Changes v2->v3:
- fix assembly argument constraint for error code
arch/xtensa/include/asm/uaccess.h | 42 +++++++++++++++----------------
1 file changed, 21 insertions(+), 21 deletions(-)
diff --git a/arch/xtensa/include/asm/uaccess.h b/arch/xtensa/include/asm/uaccess.h
index f568c00392ec..da4d35445063 100644
--- a/arch/xtensa/include/asm/uaccess.h
+++ b/arch/xtensa/include/asm/uaccess.h
@@ -132,14 +132,14 @@ do { \
#define __check_align_1 ""
#define __check_align_2 \
- " _bbci.l %3, 0, 1f \n" \
- " movi %0, %4 \n" \
+ " _bbci.l %[addr], 0, 1f \n" \
+ " movi %[err], %[efault] \n" \
" _j 2f \n"
#define __check_align_4 \
- " _bbsi.l %3, 0, 0f \n" \
- " _bbci.l %3, 1, 1f \n" \
- "0: movi %0, %4 \n" \
+ " _bbsi.l %[addr], 0, 0f \n" \
+ " _bbci.l %[addr], 1, 1f \n" \
+ "0: movi %[err], %[efault] \n" \
" _j 2f \n"
@@ -151,24 +151,24 @@ do { \
* WARNING: If you modify this macro at all, verify that the
* __check_align_* macros still work.
*/
-#define __put_user_asm(x, addr, err, align, insn, cb) \
+#define __put_user_asm(x_, addr_, err_, align, insn, cb)\
__asm__ __volatile__( \
__check_align_##align \
- "1: "insn" %2, %3, 0 \n" \
+ "1: "insn" %[x], %[addr], 0 \n" \
"2: \n" \
" .section .fixup,\"ax\" \n" \
" .align 4 \n" \
" .literal_position \n" \
"5: \n" \
- " movi %1, 2b \n" \
- " movi %0, %4 \n" \
- " jx %1 \n" \
+ " movi %[tmp], 2b \n" \
+ " movi %[err], %[efault] \n" \
+ " jx %[tmp] \n" \
" .previous \n" \
" .section __ex_table,\"a\" \n" \
" .long 1b, 5b \n" \
" .previous" \
- :"=r" (err), "=r" (cb) \
- :"r" ((int)(x)), "r" (addr), "i" (-EFAULT), "0" (err))
+ :[err] "+r"(err_), [tmp] "=r"(cb) \
+ :[x] "r"(x_), [addr] "r"(addr_), [efault] "i"(-EFAULT))
#define __get_user_nocheck(x, ptr, size) \
({ \
@@ -217,25 +217,25 @@ do { \
* WARNING: If you modify this macro at all, verify that the
* __check_align_* macros still work.
*/
-#define __get_user_asm(x, addr, err, align, insn, cb) \
-__asm__ __volatile__( \
+#define __get_user_asm(x_, addr_, err_, align, insn, cb) \
+__asm__ __volatile__( \
__check_align_##align \
- "1: "insn" %2, %3, 0 \n" \
+ "1: "insn" %[x], %[addr], 0 \n" \
"2: \n" \
" .section .fixup,\"ax\" \n" \
" .align 4 \n" \
" .literal_position \n" \
"5: \n" \
- " movi %1, 2b \n" \
- " movi %2, 0 \n" \
- " movi %0, %4 \n" \
- " jx %1 \n" \
+ " movi %[tmp], 2b \n" \
+ " movi %[x], 0 \n" \
+ " movi %[err], %[efault] \n" \
+ " jx %[tmp] \n" \
" .previous \n" \
" .section __ex_table,\"a\" \n" \
" .long 1b, 5b \n" \
" .previous" \
- :"=r" (err), "=r" (cb), "=r" (x) \
- :"r" (addr), "i" (-EFAULT), "0" (err))
+ :[err] "+r"(err_), [tmp] "=r"(cb), [x] "=r"(x_)\
+ :[addr] "r"(addr_), [efault] "i"(-EFAULT))
/*
--
2.20.1