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-rw-r--r--arch/s390/lib/uaccess.c426
1 files changed, 81 insertions, 345 deletions
diff --git a/arch/s390/lib/uaccess.c b/arch/s390/lib/uaccess.c
index c4f8039a35e8..720036fb1924 100644
--- a/arch/s390/lib/uaccess.c
+++ b/arch/s390/lib/uaccess.c
@@ -8,104 +8,44 @@
* Gerald Schaefer (gerald.schaefer@de.ibm.com)
*/
-#include <linux/jump_label.h>
#include <linux/uaccess.h>
#include <linux/export.h>
-#include <linux/errno.h>
#include <linux/mm.h>
-#include <asm/mmu_context.h>
-#include <asm/facility.h>
+#include <asm/asm-extable.h>
-#ifndef CONFIG_HAVE_MARCH_Z10_FEATURES
-static DEFINE_STATIC_KEY_FALSE(have_mvcos);
-
-static int __init uaccess_init(void)
-{
- if (test_facility(27))
- static_branch_enable(&have_mvcos);
- return 0;
-}
-early_initcall(uaccess_init);
-
-static inline int copy_with_mvcos(void)
-{
- if (static_branch_likely(&have_mvcos))
- return 1;
- return 0;
-}
-#else
-static inline int copy_with_mvcos(void)
-{
- return 1;
-}
-#endif
-
-void set_fs(mm_segment_t fs)
-{
- current->thread.mm_segment = fs;
- if (fs == USER_DS) {
- __ctl_load(S390_lowcore.user_asce, 1, 1);
- clear_cpu_flag(CIF_ASCE_PRIMARY);
- } else {
- __ctl_load(S390_lowcore.kernel_asce, 1, 1);
- set_cpu_flag(CIF_ASCE_PRIMARY);
- }
- if (fs & 1) {
- if (fs == USER_DS_SACF)
- __ctl_load(S390_lowcore.user_asce, 7, 7);
- else
- __ctl_load(S390_lowcore.kernel_asce, 7, 7);
- set_cpu_flag(CIF_ASCE_SECONDARY);
- }
-}
-EXPORT_SYMBOL(set_fs);
-
-mm_segment_t enable_sacf_uaccess(void)
+#ifdef CONFIG_DEBUG_ENTRY
+void debug_user_asce(int exit)
{
- mm_segment_t old_fs;
- unsigned long asce, cr;
+ unsigned long cr1, cr7;
- old_fs = current->thread.mm_segment;
- if (old_fs & 1)
- return old_fs;
- current->thread.mm_segment |= 1;
- asce = S390_lowcore.kernel_asce;
- if (likely(old_fs == USER_DS)) {
- __ctl_store(cr, 1, 1);
- if (cr != S390_lowcore.kernel_asce) {
- __ctl_load(S390_lowcore.kernel_asce, 1, 1);
- set_cpu_flag(CIF_ASCE_PRIMARY);
- }
- asce = S390_lowcore.user_asce;
- }
- __ctl_store(cr, 7, 7);
- if (cr != asce) {
- __ctl_load(asce, 7, 7);
- set_cpu_flag(CIF_ASCE_SECONDARY);
- }
- return old_fs;
-}
-EXPORT_SYMBOL(enable_sacf_uaccess);
+ __ctl_store(cr1, 1, 1);
+ __ctl_store(cr7, 7, 7);
+ if (cr1 == S390_lowcore.kernel_asce && cr7 == S390_lowcore.user_asce)
+ return;
+ panic("incorrect ASCE on kernel %s\n"
+ "cr1: %016lx cr7: %016lx\n"
+ "kernel: %016llx user: %016llx\n",
+ exit ? "exit" : "entry", cr1, cr7,
+ S390_lowcore.kernel_asce, S390_lowcore.user_asce);
-void disable_sacf_uaccess(mm_segment_t old_fs)
-{
- current->thread.mm_segment = old_fs;
- if (old_fs == USER_DS && test_facility(27)) {
- __ctl_load(S390_lowcore.user_asce, 1, 1);
- clear_cpu_flag(CIF_ASCE_PRIMARY);
- }
}
-EXPORT_SYMBOL(disable_sacf_uaccess);
+#endif /*CONFIG_DEBUG_ENTRY */
-static inline unsigned long copy_from_user_mvcos(void *x, const void __user *ptr,
- unsigned long size)
+static unsigned long raw_copy_from_user_key(void *to, const void __user *from,
+ unsigned long size, unsigned long key)
{
- register unsigned long reg0 asm("0") = 0x01UL;
unsigned long tmp1, tmp2;
+ union oac spec = {
+ .oac2.key = key,
+ .oac2.as = PSW_BITS_AS_SECONDARY,
+ .oac2.k = 1,
+ .oac2.a = 1,
+ };
tmp1 = -4096UL;
asm volatile(
- "0: .insn ss,0xc80000000000,0(%0,%2),0(%1),0\n"
+ " lr 0,%[spec]\n"
+ "0: mvcos 0(%2),0(%1),%0\n"
"6: jz 4f\n"
"1: algr %0,%3\n"
" slgr %1,%3\n"
@@ -116,71 +56,56 @@ static inline unsigned long copy_from_user_mvcos(void *x, const void __user *ptr
" slgr %4,%1\n"
" clgr %0,%4\n" /* copy crosses next page boundary? */
" jnh 5f\n"
- "3: .insn ss,0xc80000000000,0(%4,%2),0(%1),0\n"
+ "3: mvcos 0(%2),0(%1),%4\n"
"7: slgr %0,%4\n"
" j 5f\n"
"4: slgr %0,%0\n"
"5:\n"
EX_TABLE(0b,2b) EX_TABLE(3b,5b) EX_TABLE(6b,2b) EX_TABLE(7b,5b)
- : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
- : "d" (reg0) : "cc", "memory");
+ : "+a" (size), "+a" (from), "+a" (to), "+a" (tmp1), "=a" (tmp2)
+ : [spec] "d" (spec.val)
+ : "cc", "memory", "0");
return size;
}
-static inline unsigned long copy_from_user_mvcp(void *x, const void __user *ptr,
- unsigned long size)
+unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n)
{
- unsigned long tmp1, tmp2;
- mm_segment_t old_fs;
-
- old_fs = enable_sacf_uaccess();
- tmp1 = -256UL;
- asm volatile(
- " sacf 0\n"
- "0: mvcp 0(%0,%2),0(%1),%3\n"
- "7: jz 5f\n"
- "1: algr %0,%3\n"
- " la %1,256(%1)\n"
- " la %2,256(%2)\n"
- "2: mvcp 0(%0,%2),0(%1),%3\n"
- "8: jnz 1b\n"
- " j 5f\n"
- "3: la %4,255(%1)\n" /* %4 = ptr + 255 */
- " lghi %3,-4096\n"
- " nr %4,%3\n" /* %4 = (ptr + 255) & -4096 */
- " slgr %4,%1\n"
- " clgr %0,%4\n" /* copy crosses next page boundary? */
- " jnh 6f\n"
- "4: mvcp 0(%4,%2),0(%1),%3\n"
- "9: slgr %0,%4\n"
- " j 6f\n"
- "5: slgr %0,%0\n"
- "6: sacf 768\n"
- EX_TABLE(0b,3b) EX_TABLE(2b,3b) EX_TABLE(4b,6b)
- EX_TABLE(7b,3b) EX_TABLE(8b,3b) EX_TABLE(9b,6b)
- : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
- : : "cc", "memory");
- disable_sacf_uaccess(old_fs);
- return size;
+ return raw_copy_from_user_key(to, from, n, 0);
}
+EXPORT_SYMBOL(raw_copy_from_user);
-unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n)
+unsigned long _copy_from_user_key(void *to, const void __user *from,
+ unsigned long n, unsigned long key)
{
- if (copy_with_mvcos())
- return copy_from_user_mvcos(to, from, n);
- return copy_from_user_mvcp(to, from, n);
+ unsigned long res = n;
+
+ might_fault();
+ if (!should_fail_usercopy()) {
+ instrument_copy_from_user_before(to, from, n);
+ res = raw_copy_from_user_key(to, from, n, key);
+ instrument_copy_from_user_after(to, from, n, res);
+ }
+ if (unlikely(res))
+ memset(to + (n - res), 0, res);
+ return res;
}
-EXPORT_SYMBOL(raw_copy_from_user);
+EXPORT_SYMBOL(_copy_from_user_key);
-static inline unsigned long copy_to_user_mvcos(void __user *ptr, const void *x,
- unsigned long size)
+static unsigned long raw_copy_to_user_key(void __user *to, const void *from,
+ unsigned long size, unsigned long key)
{
- register unsigned long reg0 asm("0") = 0x010000UL;
unsigned long tmp1, tmp2;
+ union oac spec = {
+ .oac1.key = key,
+ .oac1.as = PSW_BITS_AS_SECONDARY,
+ .oac1.k = 1,
+ .oac1.a = 1,
+ };
tmp1 = -4096UL;
asm volatile(
- "0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n"
+ " lr 0,%[spec]\n"
+ "0: mvcos 0(%1),0(%2),%0\n"
"6: jz 4f\n"
"1: algr %0,%3\n"
" slgr %1,%3\n"
@@ -191,136 +116,48 @@ static inline unsigned long copy_to_user_mvcos(void __user *ptr, const void *x,
" slgr %4,%1\n"
" clgr %0,%4\n" /* copy crosses next page boundary? */
" jnh 5f\n"
- "3: .insn ss,0xc80000000000,0(%4,%1),0(%2),0\n"
+ "3: mvcos 0(%1),0(%2),%4\n"
"7: slgr %0,%4\n"
" j 5f\n"
"4: slgr %0,%0\n"
"5:\n"
EX_TABLE(0b,2b) EX_TABLE(3b,5b) EX_TABLE(6b,2b) EX_TABLE(7b,5b)
- : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
- : "d" (reg0) : "cc", "memory");
- return size;
-}
-
-static inline unsigned long copy_to_user_mvcs(void __user *ptr, const void *x,
- unsigned long size)
-{
- unsigned long tmp1, tmp2;
- mm_segment_t old_fs;
-
- old_fs = enable_sacf_uaccess();
- tmp1 = -256UL;
- asm volatile(
- " sacf 0\n"
- "0: mvcs 0(%0,%1),0(%2),%3\n"
- "7: jz 5f\n"
- "1: algr %0,%3\n"
- " la %1,256(%1)\n"
- " la %2,256(%2)\n"
- "2: mvcs 0(%0,%1),0(%2),%3\n"
- "8: jnz 1b\n"
- " j 5f\n"
- "3: la %4,255(%1)\n" /* %4 = ptr + 255 */
- " lghi %3,-4096\n"
- " nr %4,%3\n" /* %4 = (ptr + 255) & -4096 */
- " slgr %4,%1\n"
- " clgr %0,%4\n" /* copy crosses next page boundary? */
- " jnh 6f\n"
- "4: mvcs 0(%4,%1),0(%2),%3\n"
- "9: slgr %0,%4\n"
- " j 6f\n"
- "5: slgr %0,%0\n"
- "6: sacf 768\n"
- EX_TABLE(0b,3b) EX_TABLE(2b,3b) EX_TABLE(4b,6b)
- EX_TABLE(7b,3b) EX_TABLE(8b,3b) EX_TABLE(9b,6b)
- : "+a" (size), "+a" (ptr), "+a" (x), "+a" (tmp1), "=a" (tmp2)
- : : "cc", "memory");
- disable_sacf_uaccess(old_fs);
+ : "+a" (size), "+a" (to), "+a" (from), "+a" (tmp1), "=a" (tmp2)
+ : [spec] "d" (spec.val)
+ : "cc", "memory", "0");
return size;
}
unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n)
{
- if (copy_with_mvcos())
- return copy_to_user_mvcos(to, from, n);
- return copy_to_user_mvcs(to, from, n);
+ return raw_copy_to_user_key(to, from, n, 0);
}
EXPORT_SYMBOL(raw_copy_to_user);
-static inline unsigned long copy_in_user_mvcos(void __user *to, const void __user *from,
- unsigned long size)
-{
- register unsigned long reg0 asm("0") = 0x010001UL;
- unsigned long tmp1, tmp2;
-
- tmp1 = -4096UL;
- /* FIXME: copy with reduced length. */
- asm volatile(
- "0: .insn ss,0xc80000000000,0(%0,%1),0(%2),0\n"
- " jz 2f\n"
- "1: algr %0,%3\n"
- " slgr %1,%3\n"
- " slgr %2,%3\n"
- " j 0b\n"
- "2:slgr %0,%0\n"
- "3: \n"
- EX_TABLE(0b,3b)
- : "+a" (size), "+a" (to), "+a" (from), "+a" (tmp1), "=a" (tmp2)
- : "d" (reg0) : "cc", "memory");
- return size;
-}
-
-static inline unsigned long copy_in_user_mvc(void __user *to, const void __user *from,
- unsigned long size)
-{
- mm_segment_t old_fs;
- unsigned long tmp1;
-
- old_fs = enable_sacf_uaccess();
- asm volatile(
- " sacf 256\n"
- " aghi %0,-1\n"
- " jo 5f\n"
- " bras %3,3f\n"
- "0: aghi %0,257\n"
- "1: mvc 0(1,%1),0(%2)\n"
- " 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"
- " la %2,256(%2)\n"
- "3: aghi %0,-256\n"
- " jnm 2b\n"
- "4: ex %0,1b-0b(%3)\n"
- "5: slgr %0,%0\n"
- "6: sacf 768\n"
- EX_TABLE(1b,6b) EX_TABLE(2b,0b) EX_TABLE(4b,0b)
- : "+a" (size), "+a" (to), "+a" (from), "=a" (tmp1)
- : : "cc", "memory");
- disable_sacf_uaccess(old_fs);
- return size;
-}
-
-unsigned long raw_copy_in_user(void __user *to, const void __user *from, unsigned long n)
+unsigned long _copy_to_user_key(void __user *to, const void *from,
+ unsigned long n, unsigned long key)
{
- if (copy_with_mvcos())
- return copy_in_user_mvcos(to, from, n);
- return copy_in_user_mvc(to, from, n);
+ might_fault();
+ if (should_fail_usercopy())
+ return n;
+ instrument_copy_to_user(to, from, n);
+ return raw_copy_to_user_key(to, from, n, key);
}
-EXPORT_SYMBOL(raw_copy_in_user);
+EXPORT_SYMBOL(_copy_to_user_key);
-static inline unsigned long clear_user_mvcos(void __user *to, unsigned long size)
+unsigned long __clear_user(void __user *to, unsigned long size)
{
- register unsigned long reg0 asm("0") = 0x010000UL;
unsigned long tmp1, tmp2;
+ union oac spec = {
+ .oac1.as = PSW_BITS_AS_SECONDARY,
+ .oac1.a = 1,
+ };
tmp1 = -4096UL;
asm volatile(
- "0: .insn ss,0xc80000000000,0(%0,%1),0(%4),0\n"
- " jz 4f\n"
+ " lr 0,%[spec]\n"
+ "0: mvcos 0(%1),0(%4),%0\n"
+ "6: jz 4f\n"
"1: algr %0,%2\n"
" slgr %1,%2\n"
" j 0b\n"
@@ -329,116 +166,15 @@ static inline unsigned long clear_user_mvcos(void __user *to, unsigned long size
" slgr %3,%1\n"
" 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"
+ "3: mvcos 0(%1),0(%4),%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), "d" (reg0) : "cc", "memory");
+ : "a" (empty_zero_page), [spec] "d" (spec.val)
+ : "cc", "memory", "0");
return size;
}
-
-static inline unsigned long clear_user_xc(void __user *to, unsigned long size)
-{
- mm_segment_t old_fs;
- unsigned long tmp1, tmp2;
-
- old_fs = enable_sacf_uaccess();
- asm volatile(
- " sacf 256\n"
- " aghi %0,-1\n"
- " jo 5f\n"
- " bras %3,3f\n"
- " xc 0(1,%1),0(%1)\n"
- "0: aghi %0,257\n"
- " la %2,255(%1)\n" /* %2 = ptr + 255 */
- " srl %2,12\n"
- " sll %2,12\n" /* %2 = (ptr + 255) & -4096 */
- " slgr %2,%1\n"
- " clgr %0,%2\n" /* clear crosses next page boundary? */
- " jnh 5f\n"
- " aghi %2,-1\n"
- "1: ex %2,0(%3)\n"
- " aghi %2,1\n"
- " slgr %0,%2\n"
- " j 5f\n"
- "2: xc 0(256,%1),0(%1)\n"
- " 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)
- : "+a" (size), "+a" (to), "=a" (tmp1), "=a" (tmp2)
- : : "cc", "memory");
- disable_sacf_uaccess(old_fs);
- return size;
-}
-
-unsigned long __clear_user(void __user *to, unsigned long size)
-{
- if (copy_with_mvcos())
- return clear_user_mvcos(to, size);
- return clear_user_xc(to, size);
-}
EXPORT_SYMBOL(__clear_user);
-
-static inline unsigned long strnlen_user_srst(const char __user *src,
- unsigned long size)
-{
- register unsigned long reg0 asm("0") = 0;
- unsigned long tmp1, tmp2;
-
- asm volatile(
- " la %2,0(%1)\n"
- " la %3,0(%0,%1)\n"
- " slgr %0,%0\n"
- " sacf 256\n"
- "0: srst %3,%2\n"
- " 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)
- : "+a" (size), "+a" (src), "=a" (tmp1), "=a" (tmp2)
- : "d" (reg0) : "cc", "memory");
- return size;
-}
-
-unsigned long __strnlen_user(const char __user *src, unsigned long size)
-{
- mm_segment_t old_fs;
- unsigned long len;
-
- if (unlikely(!size))
- return 0;
- old_fs = enable_sacf_uaccess();
- len = strnlen_user_srst(src, size);
- disable_sacf_uaccess(old_fs);
- return len;
-}
-EXPORT_SYMBOL(__strnlen_user);
-
-long __strncpy_from_user(char *dst, const char __user *src, long size)
-{
- size_t done, len, offset, len_str;
-
- if (unlikely(size <= 0))
- return 0;
- done = 0;
- do {
- offset = (size_t)src & (L1_CACHE_BYTES - 1);
- len = min(size - done, L1_CACHE_BYTES - offset);
- if (copy_from_user(dst, src, len))
- return -EFAULT;
- len_str = strnlen(dst, len);
- done += len_str;
- src += len_str;
- dst += len_str;
- } while ((len_str == len) && (done < size));
- return done;
-}
-EXPORT_SYMBOL(__strncpy_from_user);
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.