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authorAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-09-08 01:01:14 -0300
committerAndré Fabian Silva Delgado <emulatorman@parabola.nu>2015-09-08 01:01:14 -0300
commite5fd91f1ef340da553f7a79da9540c3db711c937 (patch)
treeb11842027dc6641da63f4bcc524f8678263304a3 /arch/um/kernel
parent2a9b0348e685a63d97486f6749622b61e9e3292f (diff)
Linux-libre 4.2-gnu
Diffstat (limited to 'arch/um/kernel')
-rw-r--r--arch/um/kernel/ksyms.c2
-rw-r--r--arch/um/kernel/physmem.c7
-rw-r--r--arch/um/kernel/ptrace.c7
-rw-r--r--arch/um/kernel/skas/mmu.c7
-rw-r--r--arch/um/kernel/skas/syscall.c6
-rw-r--r--arch/um/kernel/skas/uaccess.c47
-rw-r--r--arch/um/kernel/trap.c10
-rw-r--r--arch/um/kernel/um_arch.c4
8 files changed, 43 insertions, 47 deletions
diff --git a/arch/um/kernel/ksyms.c b/arch/um/kernel/ksyms.c
index 543c04756..232b22307 100644
--- a/arch/um/kernel/ksyms.c
+++ b/arch/um/kernel/ksyms.c
@@ -42,3 +42,5 @@ EXPORT_SYMBOL(os_makedev);
EXPORT_SYMBOL(add_sigio_fd);
EXPORT_SYMBOL(ignore_sigio_fd);
EXPORT_SYMBOL(sigio_broken);
+
+EXPORT_SYMBOL(syscall);
diff --git a/arch/um/kernel/physmem.c b/arch/um/kernel/physmem.c
index 9034fc805..4c9861b42 100644
--- a/arch/um/kernel/physmem.c
+++ b/arch/um/kernel/physmem.c
@@ -8,6 +8,7 @@
#include <linux/mm.h>
#include <linux/pfn.h>
#include <asm/page.h>
+#include <asm/sections.h>
#include <as-layout.h>
#include <init.h>
#include <kern.h>
@@ -55,8 +56,6 @@ void map_memory(unsigned long virt, unsigned long phys, unsigned long len,
}
}
-extern int __syscall_stub_start;
-
/**
* setup_physmem() - Setup physical memory for UML
* @start: Start address of the physical kernel memory,
@@ -110,8 +109,8 @@ void __init setup_physmem(unsigned long start, unsigned long reserve_end,
* Special kludge - This page will be mapped in to userspace processes
* from physmem_fd, so it needs to be written out there.
*/
- os_seek_file(physmem_fd, __pa(&__syscall_stub_start));
- os_write_file(physmem_fd, &__syscall_stub_start, PAGE_SIZE);
+ os_seek_file(physmem_fd, __pa(__syscall_stub_start));
+ os_write_file(physmem_fd, __syscall_stub_start, PAGE_SIZE);
os_fsync_file(physmem_fd);
bootmap_size = init_bootmem(pfn, pfn + delta);
diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c
index 174ee5017..6a826cbb1 100644
--- a/arch/um/kernel/ptrace.c
+++ b/arch/um/kernel/ptrace.c
@@ -8,6 +8,7 @@
#include <linux/sched.h>
#include <linux/tracehook.h>
#include <asm/uaccess.h>
+#include <asm/ptrace-abi.h>
void user_enable_single_step(struct task_struct *child)
{
@@ -131,7 +132,7 @@ static void send_sigtrap(struct task_struct *tsk, struct uml_pt_regs *regs,
* XXX Check PT_DTRACE vs TIF_SINGLESTEP for singlestepping check and
* PT_PTRACED vs TIF_SYSCALL_TRACE for syscall tracing check
*/
-void syscall_trace_enter(struct pt_regs *regs)
+int syscall_trace_enter(struct pt_regs *regs)
{
audit_syscall_entry(UPT_SYSCALL_NR(&regs->regs),
UPT_SYSCALL_ARG1(&regs->regs),
@@ -140,9 +141,9 @@ void syscall_trace_enter(struct pt_regs *regs)
UPT_SYSCALL_ARG4(&regs->regs));
if (!test_thread_flag(TIF_SYSCALL_TRACE))
- return;
+ return 0;
- tracehook_report_syscall_entry(regs);
+ return tracehook_report_syscall_entry(regs);
}
void syscall_trace_leave(struct pt_regs *regs)
diff --git a/arch/um/kernel/skas/mmu.c b/arch/um/kernel/skas/mmu.c
index 94abdcc1d..fda1deba1 100644
--- a/arch/um/kernel/skas/mmu.c
+++ b/arch/um/kernel/skas/mmu.c
@@ -8,12 +8,11 @@
#include <linux/slab.h>
#include <asm/pgalloc.h>
#include <asm/pgtable.h>
+#include <asm/sections.h>
#include <as-layout.h>
#include <os.h>
#include <skas.h>
-extern int __syscall_stub_start;
-
static int init_stub_pte(struct mm_struct *mm, unsigned long proc,
unsigned long kernel)
{
@@ -93,7 +92,7 @@ void uml_setup_stubs(struct mm_struct *mm)
int err, ret;
ret = init_stub_pte(mm, STUB_CODE,
- (unsigned long) &__syscall_stub_start);
+ (unsigned long) __syscall_stub_start);
if (ret)
goto out;
@@ -101,7 +100,7 @@ void uml_setup_stubs(struct mm_struct *mm)
if (ret)
goto out;
- mm->context.stub_pages[0] = virt_to_page(&__syscall_stub_start);
+ mm->context.stub_pages[0] = virt_to_page(__syscall_stub_start);
mm->context.stub_pages[1] = virt_to_page(mm->context.id.stack);
/* dup_mmap already holds mmap_sem */
diff --git a/arch/um/kernel/skas/syscall.c b/arch/um/kernel/skas/syscall.c
index c0681e097..d9ec0068b 100644
--- a/arch/um/kernel/skas/syscall.c
+++ b/arch/um/kernel/skas/syscall.c
@@ -18,7 +18,10 @@ void handle_syscall(struct uml_pt_regs *r)
long result;
int syscall;
- syscall_trace_enter(regs);
+ if (syscall_trace_enter(regs)) {
+ result = -ENOSYS;
+ goto out;
+ }
/*
* This should go in the declaration of syscall, but when I do that,
@@ -34,6 +37,7 @@ void handle_syscall(struct uml_pt_regs *r)
result = -ENOSYS;
else result = EXECUTE_SYSCALL(syscall, regs);
+out:
PT_REGS_SET_SYSCALL_RETURN(regs, result);
syscall_trace_leave(regs);
diff --git a/arch/um/kernel/skas/uaccess.c b/arch/um/kernel/skas/uaccess.c
index 4ffb644d6..85ac8adb0 100644
--- a/arch/um/kernel/skas/uaccess.c
+++ b/arch/um/kernel/skas/uaccess.c
@@ -87,10 +87,10 @@ static int do_op_one_page(unsigned long addr, int len, int is_write,
return n;
}
-static int buffer_op(unsigned long addr, int len, int is_write,
- int (*op)(unsigned long, int, void *), void *arg)
+static long buffer_op(unsigned long addr, int len, int is_write,
+ int (*op)(unsigned long, int, void *), void *arg)
{
- int size, remain, n;
+ long size, remain, n;
size = min(PAGE_ALIGN(addr) - addr, (unsigned long) len);
remain = len;
@@ -139,18 +139,16 @@ static int copy_chunk_from_user(unsigned long from, int len, void *arg)
return 0;
}
-int copy_from_user(void *to, const void __user *from, int n)
+long __copy_from_user(void *to, const void __user *from, unsigned long n)
{
if (segment_eq(get_fs(), KERNEL_DS)) {
memcpy(to, (__force void*)from, n);
return 0;
}
- return access_ok(VERIFY_READ, from, n) ?
- buffer_op((unsigned long) from, n, 0, copy_chunk_from_user, &to):
- n;
+ return buffer_op((unsigned long) from, n, 0, copy_chunk_from_user, &to);
}
-EXPORT_SYMBOL(copy_from_user);
+EXPORT_SYMBOL(__copy_from_user);
static int copy_chunk_to_user(unsigned long to, int len, void *arg)
{
@@ -161,18 +159,16 @@ static int copy_chunk_to_user(unsigned long to, int len, void *arg)
return 0;
}
-int copy_to_user(void __user *to, const void *from, int n)
+long __copy_to_user(void __user *to, const void *from, unsigned long n)
{
if (segment_eq(get_fs(), KERNEL_DS)) {
memcpy((__force void *) to, from, n);
return 0;
}
- return access_ok(VERIFY_WRITE, to, n) ?
- buffer_op((unsigned long) to, n, 1, copy_chunk_to_user, &from) :
- n;
+ return buffer_op((unsigned long) to, n, 1, copy_chunk_to_user, &from);
}
-EXPORT_SYMBOL(copy_to_user);
+EXPORT_SYMBOL(__copy_to_user);
static int strncpy_chunk_from_user(unsigned long from, int len, void *arg)
{
@@ -188,9 +184,9 @@ static int strncpy_chunk_from_user(unsigned long from, int len, void *arg)
return 0;
}
-int strncpy_from_user(char *dst, const char __user *src, int count)
+long __strncpy_from_user(char *dst, const char __user *src, long count)
{
- int n;
+ long n;
char *ptr = dst;
if (segment_eq(get_fs(), KERNEL_DS)) {
@@ -198,16 +194,13 @@ int strncpy_from_user(char *dst, const char __user *src, int count)
return strnlen(dst, count);
}
- if (!access_ok(VERIFY_READ, src, 1))
- return -EFAULT;
-
n = buffer_op((unsigned long) src, count, 0, strncpy_chunk_from_user,
&ptr);
if (n != 0)
return -EFAULT;
return strnlen(dst, count);
}
-EXPORT_SYMBOL(strncpy_from_user);
+EXPORT_SYMBOL(__strncpy_from_user);
static int clear_chunk(unsigned long addr, int len, void *unused)
{
@@ -215,22 +208,16 @@ static int clear_chunk(unsigned long addr, int len, void *unused)
return 0;
}
-int __clear_user(void __user *mem, int len)
-{
- return buffer_op((unsigned long) mem, len, 1, clear_chunk, NULL);
-}
-
-int clear_user(void __user *mem, int len)
+unsigned long __clear_user(void __user *mem, unsigned long len)
{
if (segment_eq(get_fs(), KERNEL_DS)) {
memset((__force void*)mem, 0, len);
return 0;
}
- return access_ok(VERIFY_WRITE, mem, len) ?
- buffer_op((unsigned long) mem, len, 1, clear_chunk, NULL) : len;
+ return buffer_op((unsigned long) mem, len, 1, clear_chunk, NULL);
}
-EXPORT_SYMBOL(clear_user);
+EXPORT_SYMBOL(__clear_user);
static int strnlen_chunk(unsigned long str, int len, void *arg)
{
@@ -244,7 +231,7 @@ static int strnlen_chunk(unsigned long str, int len, void *arg)
return 0;
}
-int strnlen_user(const void __user *str, int len)
+long __strnlen_user(const void __user *str, long len)
{
int count = 0, n;
@@ -256,4 +243,4 @@ int strnlen_user(const void __user *str, int len)
return count + 1;
return 0;
}
-EXPORT_SYMBOL(strnlen_user);
+EXPORT_SYMBOL(__strnlen_user);
diff --git a/arch/um/kernel/trap.c b/arch/um/kernel/trap.c
index 8e4daf44e..557232f75 100644
--- a/arch/um/kernel/trap.c
+++ b/arch/um/kernel/trap.c
@@ -7,6 +7,7 @@
#include <linux/sched.h>
#include <linux/hardirq.h>
#include <linux/module.h>
+#include <linux/uaccess.h>
#include <asm/current.h>
#include <asm/pgtable.h>
#include <asm/tlbflush.h>
@@ -35,10 +36,10 @@ int handle_page_fault(unsigned long address, unsigned long ip,
*code_out = SEGV_MAPERR;
/*
- * If the fault was during atomic operation, don't take the fault, just
+ * If the fault was with pagefaults disabled, don't take the fault, just
* fail.
*/
- if (in_atomic())
+ if (faulthandler_disabled())
goto out_nosemaphore;
if (is_user)
@@ -219,6 +220,11 @@ unsigned long segv(struct faultinfo fi, unsigned long ip, int is_user,
show_regs(container_of(regs, struct pt_regs, regs));
panic("Segfault with no mm");
}
+ else if (!is_user && address < TASK_SIZE) {
+ show_regs(container_of(regs, struct pt_regs, regs));
+ panic("Kernel tried to access user memory at addr 0x%lx, ip 0x%lx",
+ address, ip);
+ }
if (SEGV_IS_FIXABLE(&fi))
err = handle_page_fault(address, ip, is_write, is_user,
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index 07f798f4b..16630e75f 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -248,8 +248,6 @@ EXPORT_SYMBOL(end_iomem);
#define MIN_VMALLOC (32 * 1024 * 1024)
-extern char __binary_start;
-
int __init linux_main(int argc, char **argv)
{
unsigned long avail, diff;
@@ -294,7 +292,7 @@ int __init linux_main(int argc, char **argv)
physmem_size += UML_ROUND_UP(brk_start) - UML_ROUND_UP(&_end);
}
- uml_physmem = (unsigned long) &__binary_start & PAGE_MASK;
+ uml_physmem = (unsigned long) __binary_start & PAGE_MASK;
/* Reserve up to 4M after the current brk */
uml_reserved = ROUND_4M(brk_start) + (1 << 22);