From: Heiko Carstens <hca@linux.ibm.com>
Date: Tue, 18 Oct 2022 13:39:43 +0200
Subject: s390/uaccess: add missing EX_TABLE entries to __clear_user(),
copy_in_user_mvcos(), copy_in_user_mvc(), clear_user_xc() and __strnlen_user()
Git-commit: 4e1b5a86a5edfbefc9396d41b0fc1a2ebd0101b6
Patch-mainline: v6.1-rc3
References: bsc#1205428 LTC#200501
For some exception types the instruction address points behind the
instruction that caused the exception. Take that into account and add
the missing exception table entries.
Cc: <stable@vger.kernel.org>
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Gerald Schaefer <geraldsc@de.ibm.com>
[ ptesarik: These functions are also patched:
- copy_in_user_mvcos (cf. commit a7a08b275a8bbade798c4bdaad07ade68fe7003c)
- copy_in_user_mvc (cf. commit a7a08b275a8bbade798c4bdaad07ade68fe7003c)
- clear_user_xc (cf. commit 4efd417f298bc23bc8b6ac5db5ff79af5ec92ac5)
- __strnlen_user (cf. commit e93a1cb8d2b3dccd31bde77373c8d5619f0e0a10)
Acked-by: Petr Tesarik <ptesarik@suse.com>
---
arch/s390/lib/uaccess.c | 20 ++++++++++++--------
1 file changed, 12 insertions(+), 8 deletions(-)
--- a/arch/s390/lib/uaccess.c
+++ b/arch/s390/lib/uaccess.c
@@ -214,7 +214,7 @@ static inline unsigned long copy_in_user
asm volatile(
" lgr 0,%[spec]\n"
"0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n"
- " jz 2f\n"
+ "4: jz 2f\n"
"1: algr %0,%3\n"
" slgr %1,%3\n"
" slgr %2,%3\n"
@@ -222,6 +222,7 @@ static inline unsigned long copy_in_user
"2:slgr %0,%0\n"
"3: \n"
EX_TABLE(0b,3b)
+ EX_TABLE(4b,3b)
: "+a" (size), "+a" (to), "+a" (from), "+a" (tmp1), "=a" (tmp2)
: [spec] "d" (0x810081UL)
: "cc", "memory", "0");
@@ -240,13 +241,13 @@ static inline unsigned long copy_in_user
" bras %3,3f\n"
"0: aghi %0,257\n"
"1: mvc 0(1,%1),0(%2)\n"
- " la %1,1(%1)\n"
+ "7: la %1,1(%1)\n"
" la %2,1(%2)\n"
" aghi %0,-1\n"
" jnz 1b\n"
" j 5f\n"
"2: mvc 0(256,%1),0(%2)\n"
- " la %1,256(%1)\n"
+ "8: la %1,256(%1)\n"
" la %2,256(%2)\n"
"3: aghi %0,-256\n"
" jnm 2b\n"
@@ -254,6 +255,7 @@ static inline unsigned long copy_in_user
"5: slgr %0,%0\n"
"6: sacf 768\n"
EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b)
+ EX_TABLE(7b,6b) EX_TABLE(8b,0b)
: "+a" (size), "+a" (to), "+a" (from), "=a" (tmp1)
: : "cc", "memory");
return size;
@@ -275,7 +277,7 @@ static inline unsigned long clear_user_m
asm volatile(
" lr 0,%[spec]\n"
"0: .insn ss,0xc80000000000,0(%0,%1),0(%4),0\n"
- " jz 4f\n"
+ "6: jz 4f\n"
"1: algr %0,%2\n"
" slgr %1,%2\n"
" j 0b\n"
@@ -285,11 +287,11 @@ static inline unsigned long clear_user_m
" clgr %0,%3\n" /* copy crosses next page boundary? */
" jnh 5f\n"
"3: .insn ss,0xc80000000000,0(%3,%1),0(%4),0\n"
- " slgr %0,%3\n"
+ "7: slgr %0,%3\n"
" j 5f\n"
"4: slgr %0,%0\n"
"5:\n"
- EX_TABLE(0b,2b) EX_TABLE(3b,5b)
+ EX_TABLE(0b,2b) EX_TABLE(6b,2b) EX_TABLE(3b,5b) EX_TABLE(7b,5b)
: "+a" (size), "+a" (to), "+a" (tmp1), "=a" (tmp2)
: "a" (empty_zero_page), [spec] "d" (spec.val)
: "cc", "memory", "0");
@@ -319,13 +321,14 @@ static inline unsigned long clear_user_x
" slgr %0,%2\n"
" j 5f\n"
"2: xc 0(256,%1),0(%1)\n"
- " la %1,256(%1)\n"
+ "7: la %1,256(%1)\n"
"3: aghi %0,-256\n"
" jnm 2b\n"
"4: ex %0,0(%3)\n"
"5: slgr %0,%0\n"
"6: sacf 768\n"
EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b)
+ EX_TABLE(7b,0b)
: "+a" (size), "+a" (to), "=a" (tmp1), "=a" (tmp2)
: : "cc", "memory");
return size;
@@ -351,11 +354,12 @@ static inline unsigned long strnlen_user
" slgr %0,%0\n"
" sacf 256\n"
"0: srst %3,%2\n"
- " jo 0b\n"
+ "2: jo 0b\n"
" la %0,1(%3)\n" /* strnlen_user results includes \0 */
" slgr %0,%1\n"
"1: sacf 768\n"
EX_TABLE(0b,1b)
+ EX_TABLE(2b,1b)
: "+a" (size), "+a" (src), "=a" (tmp1), "=a" (tmp2)
:
: "cc", "memory", "0");