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-rw-r--r--arch/s390/Kconfig25
-rw-r--r--arch/s390/defconfig2
-rw-r--r--arch/s390/kernel/compat_linux.c6
-rw-r--r--arch/s390/kernel/compat_linux.h31
-rw-r--r--arch/s390/kernel/compat_signal.c2
-rw-r--r--arch/s390/kernel/ipl.c4
-rw-r--r--arch/s390/kernel/process.c4
-rw-r--r--arch/s390/kernel/ptrace.c10
-rw-r--r--arch/s390/kernel/setup.c98
-rw-r--r--arch/s390/kernel/signal.c2
-rw-r--r--arch/s390/kernel/smp.c2
-rw-r--r--arch/s390/lib/uaccess_mvcos.c53
-rw-r--r--arch/s390/lib/uaccess_pt.c320
-rw-r--r--arch/s390/mm/fault.c88
-rw-r--r--arch/s390/mm/init.c6
-rw-r--r--arch/s390/mm/vmem.c14
16 files changed, 606 insertions, 61 deletions
diff --git a/arch/s390/Kconfig b/arch/s390/Kconfig
index 12272361c018..5c7e981c115b 100644
--- a/arch/s390/Kconfig
+++ b/arch/s390/Kconfig
@@ -134,6 +134,31 @@ config AUDIT_ARCH
bool
default y
+config S390_SWITCH_AMODE
+ bool "Switch kernel/user addressing modes"
+ help
+ This option allows to switch the addressing modes of kernel and user
+ space. The kernel parameter switch_amode=on will enable this feature,
+ default is disabled. Enabling this (via kernel parameter) on machines
+ earlier than IBM System z9-109 EC/BC will reduce system performance.
+
+ Note that this option will also be selected by selecting the execute
+ protection option below. Enabling the execute protection via the
+ noexec kernel parameter will also switch the addressing modes,
+ independent of the switch_amode kernel parameter.
+
+
+config S390_EXEC_PROTECT
+ bool "Data execute protection"
+ select S390_SWITCH_AMODE
+ help
+ This option allows to enable a buffer overflow protection for user
+ space programs and it also selects the addressing mode option above.
+ The kernel parameter noexec=on will enable this feature and also
+ switch the addressing modes, default is disabled. Enabling this (via
+ kernel parameter) on machines earlier than IBM System z9-109 EC/BC
+ will reduce system performance.
+
comment "Code generation options"
choice
diff --git a/arch/s390/defconfig b/arch/s390/defconfig
index 46bb38515b0d..12eb97f9c1d1 100644
--- a/arch/s390/defconfig
+++ b/arch/s390/defconfig
@@ -108,6 +108,8 @@ CONFIG_DEFAULT_MIGRATION_COST=1000000
CONFIG_COMPAT=y
CONFIG_SYSVIPC_COMPAT=y
CONFIG_AUDIT_ARCH=y
+CONFIG_S390_SWITCH_AMODE=y
+CONFIG_S390_EXEC_PROTECT=y
#
# Code generation options
diff --git a/arch/s390/kernel/compat_linux.c b/arch/s390/kernel/compat_linux.c
index cf84d697daed..666bb6daa148 100644
--- a/arch/s390/kernel/compat_linux.c
+++ b/arch/s390/kernel/compat_linux.c
@@ -69,6 +69,12 @@
#include "compat_linux.h"
+long psw_user32_bits = (PSW_BASE32_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
+ PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
+ PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
+long psw32_user_bits = (PSW32_BASE_BITS | PSW32_MASK_DAT | PSW32_ASC_HOME |
+ PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
+ PSW32_MASK_PSTATE);
/* For this source file, we want overflow handling. */
diff --git a/arch/s390/kernel/compat_linux.h b/arch/s390/kernel/compat_linux.h
index 1a18e29668ef..e89f8c0c42a0 100644
--- a/arch/s390/kernel/compat_linux.h
+++ b/arch/s390/kernel/compat_linux.h
@@ -115,37 +115,6 @@ typedef struct
__u32 addr;
} _psw_t32 __attribute__ ((aligned(8)));
-#define PSW32_MASK_PER 0x40000000UL
-#define PSW32_MASK_DAT 0x04000000UL
-#define PSW32_MASK_IO 0x02000000UL
-#define PSW32_MASK_EXT 0x01000000UL
-#define PSW32_MASK_KEY 0x00F00000UL
-#define PSW32_MASK_MCHECK 0x00040000UL
-#define PSW32_MASK_WAIT 0x00020000UL
-#define PSW32_MASK_PSTATE 0x00010000UL
-#define PSW32_MASK_ASC 0x0000C000UL
-#define PSW32_MASK_CC 0x00003000UL
-#define PSW32_MASK_PM 0x00000f00UL
-
-#define PSW32_ADDR_AMODE31 0x80000000UL
-#define PSW32_ADDR_INSN 0x7FFFFFFFUL
-
-#define PSW32_BASE_BITS 0x00080000UL
-
-#define PSW32_ASC_PRIMARY 0x00000000UL
-#define PSW32_ASC_ACCREG 0x00004000UL
-#define PSW32_ASC_SECONDARY 0x00008000UL
-#define PSW32_ASC_HOME 0x0000C000UL
-
-#define PSW32_USER_BITS (PSW32_BASE_BITS | PSW32_MASK_DAT | PSW32_ASC_HOME | \
- PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK | \
- PSW32_MASK_PSTATE)
-
-#define PSW32_MASK_MERGE(CURRENT,NEW) \
- (((CURRENT) & ~(PSW32_MASK_CC|PSW32_MASK_PM)) | \
- ((NEW) & (PSW32_MASK_CC|PSW32_MASK_PM)))
-
-
typedef struct
{
_psw_t32 psw;
diff --git a/arch/s390/kernel/compat_signal.c b/arch/s390/kernel/compat_signal.c
index 8d17b2ab6f21..887a9881d0d0 100644
--- a/arch/s390/kernel/compat_signal.c
+++ b/arch/s390/kernel/compat_signal.c
@@ -298,7 +298,7 @@ static int save_sigregs32(struct pt_regs *regs, _sigregs32 __user *sregs)
_s390_regs_common32 regs32;
int err, i;
- regs32.psw.mask = PSW32_MASK_MERGE(PSW32_USER_BITS,
+ regs32.psw.mask = PSW32_MASK_MERGE(psw32_user_bits,
(__u32)(regs->psw.mask >> 32));
regs32.psw.addr = PSW32_ADDR_AMODE31 | (__u32) regs->psw.addr;
for (i = 0; i < NUM_GPRS; i++)
diff --git a/arch/s390/kernel/ipl.c b/arch/s390/kernel/ipl.c
index 9e9972e8a52b..2c91226e1d40 100644
--- a/arch/s390/kernel/ipl.c
+++ b/arch/s390/kernel/ipl.c
@@ -1016,12 +1016,12 @@ void s390_reset_system(void)
__ctl_clear_bit(0,28);
/* Set new machine check handler */
- S390_lowcore.mcck_new_psw.mask = PSW_KERNEL_BITS & ~PSW_MASK_MCHECK;
+ S390_lowcore.mcck_new_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
S390_lowcore.mcck_new_psw.addr =
PSW_ADDR_AMODE | (unsigned long) &reset_mcck_handler;
/* Set new program check handler */
- S390_lowcore.program_new_psw.mask = PSW_KERNEL_BITS & ~PSW_MASK_MCHECK;
+ S390_lowcore.program_new_psw.mask = psw_kernel_bits & ~PSW_MASK_MCHECK;
S390_lowcore.program_new_psw.addr =
PSW_ADDR_AMODE | (unsigned long) &reset_pgm_handler;
diff --git a/arch/s390/kernel/process.c b/arch/s390/kernel/process.c
index 6603fbb41d07..5acfac654f9d 100644
--- a/arch/s390/kernel/process.c
+++ b/arch/s390/kernel/process.c
@@ -144,7 +144,7 @@ static void default_idle(void)
trace_hardirqs_on();
/* Wait for external, I/O or machine check interrupt. */
- __load_psw_mask(PSW_KERNEL_BITS | PSW_MASK_WAIT |
+ __load_psw_mask(psw_kernel_bits | PSW_MASK_WAIT |
PSW_MASK_IO | PSW_MASK_EXT);
}
@@ -190,7 +190,7 @@ int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags)
struct pt_regs regs;
memset(&regs, 0, sizeof(regs));
- regs.psw.mask = PSW_KERNEL_BITS | PSW_MASK_IO | PSW_MASK_EXT;
+ regs.psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
regs.psw.addr = (unsigned long) kernel_thread_starter | PSW_ADDR_AMODE;
regs.gprs[9] = (unsigned long) fn;
regs.gprs[10] = (unsigned long) arg;
diff --git a/arch/s390/kernel/ptrace.c b/arch/s390/kernel/ptrace.c
index 29fde70090fe..2a8f0872ea8b 100644
--- a/arch/s390/kernel/ptrace.c
+++ b/arch/s390/kernel/ptrace.c
@@ -230,9 +230,9 @@ poke_user(struct task_struct *child, addr_t addr, addr_t data)
*/
if (addr == (addr_t) &dummy->regs.psw.mask &&
#ifdef CONFIG_COMPAT
- data != PSW_MASK_MERGE(PSW_USER32_BITS, data) &&
+ data != PSW_MASK_MERGE(psw_user32_bits, data) &&
#endif
- data != PSW_MASK_MERGE(PSW_USER_BITS, data))
+ data != PSW_MASK_MERGE(psw_user_bits, data))
/* Invalid psw mask. */
return -EINVAL;
#ifndef CONFIG_64BIT
@@ -393,7 +393,7 @@ peek_user_emu31(struct task_struct *child, addr_t addr, addr_t data)
if (addr == (addr_t) &dummy32->regs.psw.mask) {
/* Fake a 31 bit psw mask. */
tmp = (__u32)(task_pt_regs(child)->psw.mask >> 32);
- tmp = PSW32_MASK_MERGE(PSW32_USER_BITS, tmp);
+ tmp = PSW32_MASK_MERGE(psw32_user_bits, tmp);
} else if (addr == (addr_t) &dummy32->regs.psw.addr) {
/* Fake a 31 bit psw address. */
tmp = (__u32) task_pt_regs(child)->psw.addr |
@@ -468,11 +468,11 @@ poke_user_emu31(struct task_struct *child, addr_t addr, addr_t data)
*/
if (addr == (addr_t) &dummy32->regs.psw.mask) {
/* Build a 64 bit psw mask from 31 bit mask. */
- if (tmp != PSW32_MASK_MERGE(PSW32_USER_BITS, tmp))
+ if (tmp != PSW32_MASK_MERGE(psw32_user_bits, tmp))
/* Invalid psw mask. */
return -EINVAL;
task_pt_regs(child)->psw.mask =
- PSW_MASK_MERGE(PSW_USER32_BITS, (__u64) tmp << 32);
+ PSW_MASK_MERGE(psw_user32_bits, (__u64) tmp << 32);
} else if (addr == (addr_t) &dummy32->regs.psw.addr) {
/* Build a 64 bit psw address from 31 bit address. */
task_pt_regs(child)->psw.addr =
diff --git a/arch/s390/kernel/setup.c b/arch/s390/kernel/setup.c
index 25bf7277d311..b1b9a931237d 100644
--- a/arch/s390/kernel/setup.c
+++ b/arch/s390/kernel/setup.c
@@ -50,6 +50,13 @@
#include <asm/page.h>
#include <asm/ptrace.h>
#include <asm/sections.h>
+#include <asm/compat.h>
+
+long psw_kernel_bits = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_PRIMARY |
+ PSW_MASK_MCHECK | PSW_DEFAULT_KEY);
+long psw_user_bits = (PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
+ PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
+ PSW_MASK_PSTATE | PSW_DEFAULT_KEY);
/*
* User copy operations.
@@ -383,6 +390,84 @@ static int __init early_parse_ipldelay(char *p)
}
early_param("ipldelay", early_parse_ipldelay);
+#ifdef CONFIG_S390_SWITCH_AMODE
+unsigned int switch_amode = 0;
+EXPORT_SYMBOL_GPL(switch_amode);
+
+static inline void set_amode_and_uaccess(unsigned long user_amode,
+ unsigned long user32_amode)
+{
+ psw_user_bits = PSW_BASE_BITS | PSW_MASK_DAT | user_amode |
+ PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
+ PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
+#ifdef CONFIG_COMPAT
+ psw_user32_bits = PSW_BASE32_BITS | PSW_MASK_DAT | user_amode |
+ PSW_MASK_IO | PSW_MASK_EXT | PSW_MASK_MCHECK |
+ PSW_MASK_PSTATE | PSW_DEFAULT_KEY;
+ psw32_user_bits = PSW32_BASE_BITS | PSW32_MASK_DAT | user32_amode |
+ PSW32_MASK_IO | PSW32_MASK_EXT | PSW32_MASK_MCHECK |
+ PSW32_MASK_PSTATE;
+#endif
+ psw_kernel_bits = PSW_BASE_BITS | PSW_MASK_DAT | PSW_ASC_HOME |
+ PSW_MASK_MCHECK | PSW_DEFAULT_KEY;
+
+ if (MACHINE_HAS_MVCOS) {
+ printk("mvcos available.\n");
+ memcpy(&uaccess, &uaccess_mvcos_switch, sizeof(uaccess));
+ } else {
+ printk("mvcos not available.\n");
+ memcpy(&uaccess, &uaccess_pt, sizeof(uaccess));
+ }
+}
+
+/*
+ * Switch kernel/user addressing modes?
+ */
+static int __init early_parse_switch_amode(char *p)
+{
+ switch_amode = 1;
+ return 0;
+}
+early_param("switch_amode", early_parse_switch_amode);
+
+#else /* CONFIG_S390_SWITCH_AMODE */
+static inline void set_amode_and_uaccess(unsigned long user_amode,
+ unsigned long user32_amode)
+{
+}
+#endif /* CONFIG_S390_SWITCH_AMODE */
+
+#ifdef CONFIG_S390_EXEC_PROTECT
+unsigned int s390_noexec = 0;
+EXPORT_SYMBOL_GPL(s390_noexec);
+
+/*
+ * Enable execute protection?
+ */
+static int __init early_parse_noexec(char *p)
+{
+ if (!strncmp(p, "off", 3))
+ return 0;
+ switch_amode = 1;
+ s390_noexec = 1;
+ return 0;
+}
+early_param("noexec", early_parse_noexec);
+#endif /* CONFIG_S390_EXEC_PROTECT */
+
+static void setup_addressing_mode(void)
+{
+ if (s390_noexec) {
+ printk("S390 execute protection active, ");
+ set_amode_and_uaccess(PSW_ASC_SECONDARY, PSW32_ASC_SECONDARY);
+ return;
+ }
+ if (switch_amode) {
+ printk("S390 address spaces switched, ");
+ set_amode_and_uaccess(PSW_ASC_PRIMARY, PSW32_ASC_PRIMARY);
+ }
+}
+
static void __init
setup_lowcore(void)
{
@@ -399,19 +484,21 @@ setup_lowcore(void)
lc->restart_psw.mask = PSW_BASE_BITS | PSW_DEFAULT_KEY;
lc->restart_psw.addr =
PSW_ADDR_AMODE | (unsigned long) restart_int_handler;
- lc->external_new_psw.mask = PSW_KERNEL_BITS;
+ if (switch_amode)
+ lc->restart_psw.mask |= PSW_ASC_HOME;
+ lc->external_new_psw.mask = psw_kernel_bits;
lc->external_new_psw.addr =
PSW_ADDR_AMODE | (unsigned long) ext_int_handler;
- lc->svc_new_psw.mask = PSW_KERNEL_BITS | PSW_MASK_IO | PSW_MASK_EXT;
+ lc->svc_new_psw.mask = psw_kernel_bits | PSW_MASK_IO | PSW_MASK_EXT;
lc->svc_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) system_call;
- lc->program_new_psw.mask = PSW_KERNEL_BITS;
+ lc->program_new_psw.mask = psw_kernel_bits;
lc->program_new_psw.addr =
PSW_ADDR_AMODE | (unsigned long)pgm_check_handler;
lc->mcck_new_psw.mask =
- PSW_KERNEL_BITS & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
+ psw_kernel_bits & ~PSW_MASK_MCHECK & ~PSW_MASK_DAT;
lc->mcck_new_psw.addr =
PSW_ADDR_AMODE | (unsigned long) mcck_int_handler;
- lc->io_new_psw.mask = PSW_KERNEL_BITS;
+ lc->io_new_psw.mask = psw_kernel_bits;
lc->io_new_psw.addr = PSW_ADDR_AMODE | (unsigned long) io_int_handler;
lc->ipl_device = S390_lowcore.ipl_device;
lc->jiffy_timer = -1LL;
@@ -645,6 +732,7 @@ setup_arch(char **cmdline_p)
parse_early_param();
setup_memory_end();
+ setup_addressing_mode();
setup_memory();
setup_resources();
setup_lowcore();
diff --git a/arch/s390/kernel/signal.c b/arch/s390/kernel/signal.c
index 4c8a7954ef48..554f9cf7499c 100644
--- a/arch/s390/kernel/signal.c
+++ b/arch/s390/kernel/signal.c
@@ -119,7 +119,7 @@ static int save_sigregs(struct pt_regs *regs, _sigregs __user *sregs)
/* Copy a 'clean' PSW mask to the user to avoid leaking
information about whether PER is currently on. */
- user_sregs.regs.psw.mask = PSW_MASK_MERGE(PSW_USER_BITS, regs->psw.mask);
+ user_sregs.regs.psw.mask = PSW_MASK_MERGE(psw_user_bits, regs->psw.mask);
user_sregs.regs.psw.addr = regs->psw.addr;
memcpy(&user_sregs.regs.gprs, &regs->gprs, sizeof(sregs->regs.gprs));
memcpy(&user_sregs.regs.acrs, current->thread.acrs,
diff --git a/arch/s390/kernel/smp.c b/arch/s390/kernel/smp.c
index 3cb7e1032072..cb155d9fd749 100644
--- a/arch/s390/kernel/smp.c
+++ b/arch/s390/kernel/smp.c
@@ -244,7 +244,7 @@ static inline void do_wait_for_stop(void)
void smp_send_stop(void)
{
/* Disable all interrupts/machine checks */
- __load_psw_mask(PSW_KERNEL_BITS & ~PSW_MASK_MCHECK);
+ __load_psw_mask(psw_kernel_bits & ~PSW_MASK_MCHECK);
/* write magic number to zero page (absolute 0) */
lowcore_ptr[smp_processor_id()]->panic_magic = __PANIC_MAGIC;
diff --git a/arch/s390/lib/uaccess_mvcos.c b/arch/s390/lib/uaccess_mvcos.c
index 78c48f88f5f7..6d8772339d76 100644
--- a/arch/s390/lib/uaccess_mvcos.c
+++ b/arch/s390/lib/uaccess_mvcos.c
@@ -162,6 +162,44 @@ static size_t clear_user_mvcos(size_t size, void __user *to)
return size;
}
+static size_t strnlen_user_mvcos(size_t count, const char __user *src)
+{
+ char buf[256];
+ int rc;
+ size_t done, len, len_str;
+
+ done = 0;
+ do {
+ len = min(count - done, (size_t) 256);
+ rc = uaccess.copy_from_user(len, src + done, buf);
+ if (unlikely(rc == len))
+ return 0;
+ len -= rc;
+ len_str = strnlen(buf, len);
+ done += len_str;
+ } while ((len_str == len) && (done < count));
+ return done + 1;
+}
+
+static size_t strncpy_from_user_mvcos(size_t count, const char __user *src,
+ char *dst)
+{
+ int rc;
+ size_t done, len, len_str;
+
+ done = 0;
+ do {
+ len = min(count - done, (size_t) 4096);
+ rc = uaccess.copy_from_user(len, src + done, dst);
+ if (unlikely(rc == len))
+ return -EFAULT;
+ len -= rc;
+ len_str = strnlen(dst, len);
+ done += len_str;
+ } while ((len_str == len) && (done < count));
+ return done;
+}
+
struct uaccess_ops uaccess_mvcos = {
.copy_from_user = copy_from_user_mvcos_check,
.copy_from_user_small = copy_from_user_std,
@@ -174,3 +212,18 @@ struct uaccess_ops uaccess_mvcos = {
.futex_atomic_op = futex_atomic_op_std,
.futex_atomic_cmpxchg = futex_atomic_cmpxchg_std,
};
+
+#ifdef CONFIG_S390_SWITCH_AMODE
+struct uaccess_ops uaccess_mvcos_switch = {
+ .copy_from_user = copy_from_user_mvcos,
+ .copy_from_user_small = copy_from_user_mvcos,
+ .copy_to_user = copy_to_user_mvcos,
+ .copy_to_user_small = copy_to_user_mvcos,
+ .copy_in_user = copy_in_user_mvcos,
+ .clear_user = clear_user_mvcos,
+ .strnlen_user = strnlen_user_mvcos,
+ .strncpy_from_user = strncpy_from_user_mvcos,
+ .futex_atomic_op = futex_atomic_op_pt,
+ .futex_atomic_cmpxchg = futex_atomic_cmpxchg_pt,
+};
+#endif
diff --git a/arch/s390/lib/uaccess_pt.c b/arch/s390/lib/uaccess_pt.c
index 24ead559c7bb..637192fa7c9a 100644
--- a/arch/s390/lib/uaccess_pt.c
+++ b/arch/s390/lib/uaccess_pt.c
@@ -1,7 +1,8 @@
/*
* arch/s390/lib/uaccess_pt.c
*
- * User access functions based on page table walks.
+ * User access functions based on page table walks for enhanced
+ * system layout without hardware support.
*
* Copyright IBM Corp. 2006
* Author(s): Gerald Schaefer (gerald.schaefer@de.ibm.com)
@@ -134,6 +135,49 @@ fault:
goto retry;
}
+/*
+ * Do DAT for user address by page table walk, return kernel address.
+ * This function needs to be called with current->mm->page_table_lock held.
+ */
+static inline unsigned long __dat_user_addr(unsigned long uaddr)
+{
+ struct mm_struct *mm = current->mm;
+ unsigned long pfn, ret;
+ pgd_t *pgd;
+ pmd_t *pmd;
+ pte_t *pte;
+ int rc;
+
+ ret = 0;
+retry:
+ pgd = pgd_offset(mm, uaddr);
+ if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
+ goto fault;
+
+ pmd = pmd_offset(pgd, uaddr);
+ if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
+ goto fault;
+
+ pte = pte_offset_map(pmd, uaddr);
+ if (!pte || !pte_present(*pte))
+ goto fault;
+
+ pfn = pte_pfn(*pte);
+ if (!pfn_valid(pfn))
+ goto out;
+
+ ret = (pfn << PAGE_SHIFT) + (uaddr & (PAGE_SIZE - 1));
+out:
+ return ret;
+fault:
+ spin_unlock(&mm->page_table_lock);
+ rc = __handle_fault(mm, uaddr, 0);
+ spin_lock(&mm->page_table_lock);
+ if (rc)
+ goto out;
+ goto retry;
+}
+
size_t copy_from_user_pt(size_t n, const void __user *from, void *to)
{
size_t rc;
@@ -156,3 +200,277 @@ size_t copy_to_user_pt(size_t n, void __user *to, const void *from)
}
return __user_copy_pt((unsigned long) to, (void *) from, n, 1);
}
+
+static size_t clear_user_pt(size_t n, void __user *to)
+{
+ long done, size, ret;
+
+ if (segment_eq(get_fs(), KERNEL_DS)) {
+ memset((void __kernel __force *) to, 0, n);
+ return 0;
+ }
+ done = 0;
+ do {
+ if (n - done > PAGE_SIZE)
+ size = PAGE_SIZE;
+ else
+ size = n - done;
+ ret = __user_copy_pt((unsigned long) to + done,
+ &empty_zero_page, size, 1);
+ done += size;
+ if (ret)
+ return ret + n - done;
+ } while (done < n);
+ return 0;
+}
+
+static size_t strnlen_user_pt(size_t count, const char __user *src)
+{
+ char *addr;
+ unsigned long uaddr = (unsigned long) src;
+ struct mm_struct *mm = current->mm;
+ unsigned long offset, pfn, done, len;
+ pgd_t *pgd;
+ pmd_t *pmd;
+ pte_t *pte;
+ size_t len_str;
+
+ if (segment_eq(get_fs(), KERNEL_DS))
+ return strnlen((const char __kernel __force *) src, count) + 1;
+ done = 0;
+retry:
+ spin_lock(&mm->page_table_lock);
+ do {
+ pgd = pgd_offset(mm, uaddr);
+ if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
+ goto fault;
+
+ pmd = pmd_offset(pgd, uaddr);
+ if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
+ goto fault;
+
+ pte = pte_offset_map(pmd, uaddr);
+ if (!pte || !pte_present(*pte))
+ goto fault;
+
+ pfn = pte_pfn(*pte);
+ if (!pfn_valid(pfn)) {
+ done = -1;
+ goto out;
+ }
+
+ offset = uaddr & (PAGE_SIZE-1);
+ addr = (char *)(pfn << PAGE_SHIFT) + offset;
+ len = min(count - done, PAGE_SIZE - offset);
+ len_str = strnlen(addr, len);
+ done += len_str;
+ uaddr += len_str;
+ } while ((len_str == len) && (done < count));
+out:
+ spin_unlock(&mm->page_table_lock);
+ return done + 1;
+fault:
+ spin_unlock(&mm->page_table_lock);
+ if (__handle_fault(mm, uaddr, 0)) {
+ return 0;
+ }
+ goto retry;
+}
+
+static size_t strncpy_from_user_pt(size_t count, const char __user *src,
+ char *dst)
+{
+ size_t n = strnlen_user_pt(count, src);
+
+ if (!n)
+ return -EFAULT;
+ if (n > count)
+ n = count;
+ if (segment_eq(get_fs(), KERNEL_DS)) {
+ memcpy(dst, (const char __kernel __force *) src, n);
+ if (dst[n-1] == '\0')
+ return n-1;
+ else
+ return n;
+ }
+ if (__user_copy_pt((unsigned long) src, dst, n, 0))
+ return -EFAULT;
+ if (dst[n-1] == '\0')
+ return n-1;
+ else
+ return n;
+}
+
+static size_t copy_in_user_pt(size_t n, void __user *to,
+ const void __user *from)
+{
+ struct mm_struct *mm = current->mm;
+ unsigned long offset_from, offset_to, offset_max, pfn_from, pfn_to,
+ uaddr, done, size;
+ unsigned long uaddr_from = (unsigned long) from;
+ unsigned long uaddr_to = (unsigned long) to;
+ pgd_t *pgd_from, *pgd_to;
+ pmd_t *pmd_from, *pmd_to;
+ pte_t *pte_from, *pte_to;
+ int write_user;
+
+ done = 0;
+retry:
+ spin_lock(&mm->page_table_lock);
+ do {
+ pgd_from = pgd_offset(mm, uaddr_from);
+ if (pgd_none(*pgd_from) || unlikely(pgd_bad(*pgd_from))) {
+ uaddr = uaddr_from;
+ write_user = 0;
+ goto fault;
+ }
+ pgd_to = pgd_offset(mm, uaddr_to);
+ if (pgd_none(*pgd_to) || unlikely(pgd_bad(*pgd_to))) {
+ uaddr = uaddr_to;
+ write_user = 1;
+ goto fault;
+ }
+
+ pmd_from = pmd_offset(pgd_from, uaddr_from);
+ if (pmd_none(*pmd_from) || unlikely(pmd_bad(*pmd_from))) {
+ uaddr = uaddr_from;
+ write_user = 0;
+ goto fault;
+ }
+ pmd_to = pmd_offset(pgd_to, uaddr_to);
+ if (pmd_none(*pmd_to) || unlikely(pmd_bad(*pmd_to))) {
+ uaddr = uaddr_to;
+ write_user = 1;
+ goto fault;
+ }
+
+ pte_from = pte_offset_map(pmd_from, uaddr_from);
+ if (!pte_from || !pte_present(*pte_from)) {
+ uaddr = uaddr_from;
+ write_user = 0;
+ goto fault;
+ }
+ pte_to = pte_offset_map(pmd_to, uaddr_to);
+ if (!pte_to || !pte_present(*pte_to) || !pte_write(*pte_to)) {
+ uaddr = uaddr_to;
+ write_user = 1;
+ goto fault;
+ }
+
+ pfn_from = pte_pfn(*pte_from);
+ if (!pfn_valid(pfn_from))
+ goto out;
+ pfn_to = pte_pfn(*pte_to);
+ if (!pfn_valid(pfn_to))
+ goto out;
+
+ offset_from = uaddr_from & (PAGE_SIZE-1);
+ offset_to = uaddr_from & (PAGE_SIZE-1);
+ offset_max = max(offset_from, offset_to);
+ size = min(n - done, PAGE_SIZE - offset_max);
+
+ memcpy((void *)(pfn_to << PAGE_SHIFT) + offset_to,
+ (void *)(pfn_from << PAGE_SHIFT) + offset_from, size);
+ done += size;
+ uaddr_from += size;
+ uaddr_to += size;
+ } while (done < n);
+out:
+ spin_unlock(&mm->page_table_lock);
+ return n - done;
+fault:
+ spin_unlock(&mm->page_table_lock);
+ if (__handle_fault(mm, uaddr, write_user))
+ return n - done;
+ goto retry;
+}
+
+#define __futex_atomic_op(insn, ret, oldval, newval, uaddr, oparg) \
+ asm volatile("0: l %1,0(%6)\n" \
+ "1: " insn \
+ "2: cs %1,%2,0(%6)\n" \
+ "3: jl 1b\n" \
+ " lhi %0,0\n" \
+ "4:\n" \
+ EX_TABLE(0b,4b) EX_TABLE(2b,4b) EX_TABLE(3b,4b) \
+ : "=d" (ret), "=&d" (oldval), "=&d" (newval), \
+ "=m" (*uaddr) \
+ : "0" (-EFAULT), "d" (oparg), "a" (uaddr), \
+ "m" (*uaddr) : "cc" );
+
+int futex_atomic_op_pt(int op, int __user *uaddr, int oparg, int *old)
+{
+ int oldval = 0, newval, ret;
+
+ spin_lock(&current->mm->page_table_lock);
+ uaddr = (int __user *) __dat_user_addr((unsigned long) uaddr);
+ if (!uaddr) {
+ spin_unlock(&current->mm->page_table_lock);
+ return -EFAULT;
+ }
+ get_page(virt_to_page(uaddr));
+ spin_unlock(&current->mm->page_table_lock);
+ switch (op) {
+ case FUTEX_OP_SET:
+ __futex_atomic_op("lr %2,%5\n",
+ ret, oldval, newval, uaddr, oparg);
+ break;
+ case FUTEX_OP_ADD:
+ __futex_atomic_op("lr %2,%1\nar %2,%5\n",
+ ret, oldval, newval, uaddr, oparg);
+ break;
+ case FUTEX_OP_OR:
+ __futex_atomic_op("lr %2,%1\nor %2,%5\n",
+ ret, oldval, newval, uaddr, oparg);
+ break;
+ case FUTEX_OP_ANDN:
+ __futex_atomic_op("lr %2,%1\nnr %2,%5\n",
+ ret, oldval, newval, uaddr, oparg);
+ break;
+ case FUTEX_OP_XOR:
+ __futex_atomic_op("lr %2,%1\nxr %2,%5\n",
+ ret, oldval, newval, uaddr, oparg);
+ break;
+ default:
+ ret = -ENOSYS;
+ }
+ put_page(virt_to_page(uaddr));
+ *old = oldval;
+ return ret;
+}
+
+int futex_atomic_cmpxchg_pt(int __user *uaddr, int oldval, int newval)
+{
+ int ret;
+
+ spin_lock(&current->mm->page_table_lock);
+ uaddr = (int __user *) __dat_user_addr((unsigned long) uaddr);
+ if (!uaddr) {
+ spin_unlock(&current->mm->page_table_lock);
+ return -EFAULT;
+ }
+ get_page(virt_to_page(uaddr));
+ spin_unlock(&current->mm->page_table_lock);
+ asm volatile(" cs %1,%4,0(%5)\n"
+ "0: lr %0,%1\n"
+ "1:\n"
+ EX_TABLE(0b,1b)
+ : "=d" (ret), "+d" (oldval), "=m" (*uaddr)
+ : "0" (-EFAULT), "d" (newval), "a" (uaddr), "m" (*uaddr)
+ : "cc", "memory" );
+ put_page(virt_to_page(uaddr));
+ return ret;
+}
+
+struct uaccess_ops uaccess_pt = {
+ .copy_from_user = copy_from_user_pt,
+ .copy_from_user_small = copy_from_user_pt,
+ .copy_to_user = copy_to_user_pt,
+ .copy_to_user_small = copy_to_user_pt,
+ .copy_in_user = copy_in_user_pt,
+ .clear_user = clear_user_pt,
+ .strnlen_user = strnlen_user_pt,
+ .strncpy_from_user = strncpy_from_user_pt,
+ .futex_atomic_op = futex_atomic_op_pt,
+ .futex_atomic_cmpxchg = futex_atomic_cmpxchg_pt,
+};
diff --git a/arch/s390/mm/fault.c b/arch/s390/mm/fault.c
index 3382e29f34a4..9ff143e87746 100644
--- a/arch/s390/mm/fault.c
+++ b/arch/s390/mm/fault.c
@@ -137,7 +137,9 @@ static int __check_access_register(struct pt_regs *regs, int error_code)
/*
* Check which address space the address belongs to.
- * Returns 1 for user space and 0 for kernel space.
+ * May return 1 or 2 for user space and 0 for kernel space.
+ * Returns 2 for user space in primary addressing mode with
+ * CONFIG_S390_EXEC_PROTECT on and kernel parameter noexec=on.
*/
static inline int check_user_space(struct pt_regs *regs, int error_code)
{
@@ -154,7 +156,7 @@ static inline int check_user_space(struct pt_regs *regs, int error_code)
return __check_access_register(regs, error_code);
if (descriptor == 2)
return current->thread.mm_segment.ar4;
- return descriptor != 0;
+ return ((descriptor != 0) ^ (switch_amode)) << s390_noexec;
}
/*
@@ -183,6 +185,77 @@ static void do_sigsegv(struct pt_regs *regs, unsigned long error_code,
force_sig_info(SIGSEGV, &si, current);
}
+#ifdef CONFIG_S390_EXEC_PROTECT
+extern long sys_sigreturn(struct pt_regs *regs);
+extern long sys_rt_sigreturn(struct pt_regs *regs);
+extern long sys32_sigreturn(struct pt_regs *regs);
+extern long sys32_rt_sigreturn(struct pt_regs *regs);
+
+static inline void do_sigreturn(struct mm_struct *mm, struct pt_regs *regs,
+ int rt)
+{
+ up_read(&mm->mmap_sem);
+ clear_tsk_thread_flag(current, TIF_SINGLE_STEP);
+#ifdef CONFIG_COMPAT
+ if (test_tsk_thread_flag(current, TIF_31BIT)) {
+ if (rt)
+ sys32_rt_sigreturn(regs);
+ else
+ sys32_sigreturn(regs);
+ return;
+ }
+#endif /* CONFIG_COMPAT */
+ if (rt)
+ sys_rt_sigreturn(regs);
+ else
+ sys_sigreturn(regs);
+ return;
+}
+
+static int signal_return(struct mm_struct *mm, struct pt_regs *regs,
+ unsigned long address, unsigned long error_code)
+{
+ pgd_t *pgd;
+ pmd_t *pmd;
+ pte_t *pte;
+ u16 *instruction;
+ unsigned long pfn, uaddr = regs->psw.addr;
+
+ spin_lock(&mm->page_table_lock);
+ pgd = pgd_offset(mm, uaddr);
+ if (pgd_none(*pgd) || unlikely(pgd_bad(*pgd)))
+ goto out_fault;
+ pmd = pmd_offset(pgd, uaddr);
+ if (pmd_none(*pmd) || unlikely(pmd_bad(*pmd)))
+ goto out_fault;
+ pte = pte_offset_map(pmd_offset(pgd_offset(mm, uaddr), uaddr), uaddr);
+ if (!pte || !pte_present(*pte))
+ goto out_fault;
+ pfn = pte_pfn(*pte);
+ if (!pfn_valid(pfn))
+ goto out_fault;
+ spin_unlock(&mm->page_table_lock);
+
+ instruction = (u16 *) ((pfn << PAGE_SHIFT) + (uaddr & (PAGE_SIZE-1)));
+ if (*instruction == 0x0a77)
+ do_sigreturn(mm, regs, 0);
+ else if (*instruction == 0x0aad)
+ do_sigreturn(mm, regs, 1);
+ else {
+ printk("- XXX - do_exception: task = %s, primary, NO EXEC "
+ "-> SIGSEGV\n", current->comm);
+ up_read(&mm->mmap_sem);
+ current->thread.prot_addr = address;
+ current->thread.trap_no = error_code;
+ do_sigsegv(regs, error_code, SEGV_MAPERR, address);
+ }
+ return 0;
+out_fault:
+ spin_unlock(&mm->page_table_lock);
+ return -EFAULT;
+}
+#endif /* CONFIG_S390_EXEC_PROTECT */
+
/*
* This routine handles page faults. It determines the address,
* and the problem, and then passes it off to one of the appropriate
@@ -260,6 +333,17 @@ do_exception(struct pt_regs *regs, unsigned long error_code, int is_protection)
vma = find_vma(mm, address);
if (!vma)
goto bad_area;
+
+#ifdef CONFIG_S390_EXEC_PROTECT
+ if (unlikely((user_address == 2) && !(vma->vm_flags & VM_EXEC)))
+ if (!signal_return(mm, regs, address, error_code))
+ /*
+ * signal_return() has done an up_read(&mm->mmap_sem)
+ * if it returns 0.
+ */
+ return;
+#endif
+
if (vma->vm_start <= address)
goto good_area;
if (!(vma->vm_flags & VM_GROWSDOWN))
diff --git a/arch/s390/mm/init.c b/arch/s390/mm/init.c
index 0e7e9acab9e1..162a338a5575 100644
--- a/arch/s390/mm/init.c
+++ b/arch/s390/mm/init.c
@@ -104,7 +104,7 @@ static void __init setup_ro_region(void)
pmd = pmd_offset(pgd, address);
pte = pte_offset_kernel(pmd, address);
new_pte = mk_pte_phys(address, __pgprot(_PAGE_RO));
- set_pte(pte, new_pte);
+ *pte = new_pte;
}
}
@@ -124,11 +124,11 @@ void __init paging_init(void)
#ifdef CONFIG_64BIT
pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERN_REGION_TABLE;
for (i = 0; i < PTRS_PER_PGD; i++)
- pgd_clear(pg_dir + i);
+ pgd_clear_kernel(pg_dir + i);
#else
pgdir_k = (__pa(swapper_pg_dir) & PAGE_MASK) | _KERNSEG_TABLE;
for (i = 0; i < PTRS_PER_PGD; i++)
- pmd_clear((pmd_t *)(pg_dir + i));
+ pmd_clear_kernel((pmd_t *)(pg_dir + i));
#endif
vmem_map_init();
setup_ro_region();
diff --git a/arch/s390/mm/vmem.c b/arch/s390/mm/vmem.c
index cd3d93e8c211..92a565190028 100644
--- a/arch/s390/mm/vmem.c
+++ b/arch/s390/mm/vmem.c
@@ -82,7 +82,7 @@ static inline pmd_t *vmem_pmd_alloc(void)
if (!pmd)
return NULL;
for (i = 0; i < PTRS_PER_PMD; i++)
- pmd_clear(pmd + i);
+ pmd_clear_kernel(pmd + i);
return pmd;
}
@@ -97,7 +97,7 @@ static inline pte_t *vmem_pte_alloc(void)
return NULL;
pte_val(empty_pte) = _PAGE_TYPE_EMPTY;
for (i = 0; i < PTRS_PER_PTE; i++)
- set_pte(pte + i, empty_pte);
+ pte[i] = empty_pte;
return pte;
}
@@ -119,7 +119,7 @@ static int vmem_add_range(unsigned long start, unsigned long size)
pm_dir = vmem_pmd_alloc();
if (!pm_dir)
goto out;
- pgd_populate(&init_mm, pg_dir, pm_dir);
+ pgd_populate_kernel(&init_mm, pg_dir, pm_dir);
}
pm_dir = pmd_offset(pg_dir, address);
@@ -132,7 +132,7 @@ static int vmem_add_range(unsigned long start, unsigned long size)
pt_dir = pte_offset_kernel(pm_dir, address);
pte = pfn_pte(address >> PAGE_SHIFT, PAGE_KERNEL);
- set_pte(pt_dir, pte);
+ *pt_dir = pte;
}
ret = 0;
out:
@@ -161,7 +161,7 @@ static void vmem_remove_range(unsigned long start, unsigned long size)
if (pmd_none(*pm_dir))
continue;
pt_dir = pte_offset_kernel(pm_dir, address);
- set_pte(pt_dir, pte);
+ *pt_dir = pte;
}
flush_tlb_kernel_range(start, start + size);
}
@@ -191,7 +191,7 @@ static int vmem_add_mem_map(unsigned long start, unsigned long size)
pm_dir = vmem_pmd_alloc();
if (!pm_dir)
goto out;
- pgd_populate(&init_mm, pg_dir, pm_dir);
+ pgd_populate_kernel(&init_mm, pg_dir, pm_dir);
}
pm_dir = pmd_offset(pg_dir, address);
@@ -210,7 +210,7 @@ static int vmem_add_mem_map(unsigned long start, unsigned long size)
if (!new_page)
goto out;
pte = pfn_pte(new_page >> PAGE_SHIFT, PAGE_KERNEL);
- set_pte(pt_dir, pte);
+ *pt_dir = pte;
}
}
ret = 0;
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-01 12:33:48 +0000