[PATCH] uml: skas0 stubs now check system call return values
Change syscall-stub's data to include a "expected retval".
Stub now checks syscalls retval and aborts execution of syscall list, if
retval != expected retval.
run_syscall_stub prints the data of the failed syscall, using the data pointer
and retval written by the stub to the beginning of the stack.
one_syscall_stub is removed, to simplify code, because only some instructions
are saved by one_syscall_stub, no host-syscall.
Using the stub with additional data (modify_ldt via stub)
is prepared also.
Signed-off-by: Bodo Stroesser <bstroesser@fujitsu-siemens.com>
Signed-off-by: Jeff Dike <jdike@addtoit.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/arch/um/kernel/tlb.c b/arch/um/kernel/tlb.c
index 7d914bb..80ed618 100644
--- a/arch/um/kernel/tlb.c
+++ b/arch/um/kernel/tlb.c
@@ -16,115 +16,117 @@
#include "os.h"
static int add_mmap(unsigned long virt, unsigned long phys, unsigned long len,
- int r, int w, int x, struct host_vm_op *ops, int index,
+ int r, int w, int x, struct host_vm_op *ops, int *index,
int last_filled, union mm_context *mmu, void **flush,
- void *(*do_ops)(union mm_context *, struct host_vm_op *,
- int, int, void *))
+ int (*do_ops)(union mm_context *, struct host_vm_op *,
+ int, int, void **))
{
__u64 offset;
struct host_vm_op *last;
- int fd;
+ int fd, ret = 0;
fd = phys_mapping(phys, &offset);
- if(index != -1){
- last = &ops[index];
+ if(*index != -1){
+ last = &ops[*index];
if((last->type == MMAP) &&
(last->u.mmap.addr + last->u.mmap.len == virt) &&
(last->u.mmap.r == r) && (last->u.mmap.w == w) &&
(last->u.mmap.x == x) && (last->u.mmap.fd == fd) &&
(last->u.mmap.offset + last->u.mmap.len == offset)){
last->u.mmap.len += len;
- return index;
+ return 0;
}
}
- if(index == last_filled){
- *flush = (*do_ops)(mmu, ops, last_filled, 0, *flush);
- index = -1;
+ if(*index == last_filled){
+ ret = (*do_ops)(mmu, ops, last_filled, 0, flush);
+ *index = -1;
}
- ops[++index] = ((struct host_vm_op) { .type = MMAP,
- .u = { .mmap = {
- .addr = virt,
- .len = len,
- .r = r,
- .w = w,
- .x = x,
- .fd = fd,
- .offset = offset }
- } });
- return index;
+ ops[++*index] = ((struct host_vm_op) { .type = MMAP,
+ .u = { .mmap = {
+ .addr = virt,
+ .len = len,
+ .r = r,
+ .w = w,
+ .x = x,
+ .fd = fd,
+ .offset = offset }
+ } });
+ return ret;
}
static int add_munmap(unsigned long addr, unsigned long len,
- struct host_vm_op *ops, int index, int last_filled,
+ struct host_vm_op *ops, int *index, int last_filled,
union mm_context *mmu, void **flush,
- void *(*do_ops)(union mm_context *, struct host_vm_op *,
- int, int, void *))
+ int (*do_ops)(union mm_context *, struct host_vm_op *,
+ int, int, void **))
{
struct host_vm_op *last;
+ int ret = 0;
- if(index != -1){
- last = &ops[index];
+ if(*index != -1){
+ last = &ops[*index];
if((last->type == MUNMAP) &&
(last->u.munmap.addr + last->u.mmap.len == addr)){
last->u.munmap.len += len;
- return index;
+ return 0;
}
}
- if(index == last_filled){
- *flush = (*do_ops)(mmu, ops, last_filled, 0, *flush);
- index = -1;
+ if(*index == last_filled){
+ ret = (*do_ops)(mmu, ops, last_filled, 0, flush);
+ *index = -1;
}
- ops[++index] = ((struct host_vm_op) { .type = MUNMAP,
- .u = { .munmap = {
- .addr = addr,
- .len = len } } });
- return index;
+ ops[++*index] = ((struct host_vm_op) { .type = MUNMAP,
+ .u = { .munmap = {
+ .addr = addr,
+ .len = len } } });
+ return ret;
}
static int add_mprotect(unsigned long addr, unsigned long len, int r, int w,
- int x, struct host_vm_op *ops, int index,
+ int x, struct host_vm_op *ops, int *index,
int last_filled, union mm_context *mmu, void **flush,
- void *(*do_ops)(union mm_context *,
- struct host_vm_op *, int, int, void *))
+ int (*do_ops)(union mm_context *, struct host_vm_op *,
+ int, int, void **))
{
struct host_vm_op *last;
+ int ret = 0;
- if(index != -1){
- last = &ops[index];
+ if(*index != -1){
+ last = &ops[*index];
if((last->type == MPROTECT) &&
(last->u.mprotect.addr + last->u.mprotect.len == addr) &&
(last->u.mprotect.r == r) && (last->u.mprotect.w == w) &&
(last->u.mprotect.x == x)){
last->u.mprotect.len += len;
- return index;
+ return 0;
}
}
- if(index == last_filled){
- *flush = (*do_ops)(mmu, ops, last_filled, 0, *flush);
- index = -1;
+ if(*index == last_filled){
+ ret = (*do_ops)(mmu, ops, last_filled, 0, flush);
+ *index = -1;
}
- ops[++index] = ((struct host_vm_op) { .type = MPROTECT,
- .u = { .mprotect = {
- .addr = addr,
- .len = len,
- .r = r,
- .w = w,
- .x = x } } });
- return index;
+ ops[++*index] = ((struct host_vm_op) { .type = MPROTECT,
+ .u = { .mprotect = {
+ .addr = addr,
+ .len = len,
+ .r = r,
+ .w = w,
+ .x = x } } });
+ return ret;
}
#define ADD_ROUND(n, inc) (((n) + (inc)) & ~((inc) - 1))
void fix_range_common(struct mm_struct *mm, unsigned long start_addr,
unsigned long end_addr, int force,
- void *(*do_ops)(union mm_context *, struct host_vm_op *,
- int, int, void *))
+ int (*do_ops)(union mm_context *, struct host_vm_op *,
+ int, int, void **))
{
pgd_t *npgd;
pud_t *npud;
@@ -136,20 +138,21 @@
struct host_vm_op ops[1];
void *flush = NULL;
int op_index = -1, last_op = sizeof(ops) / sizeof(ops[0]) - 1;
+ int ret = 0;
if(mm == NULL) return;
ops[0].type = NONE;
- for(addr = start_addr; addr < end_addr;){
+ for(addr = start_addr; addr < end_addr && !ret;){
npgd = pgd_offset(mm, addr);
if(!pgd_present(*npgd)){
end = ADD_ROUND(addr, PGDIR_SIZE);
if(end > end_addr)
end = end_addr;
if(force || pgd_newpage(*npgd)){
- op_index = add_munmap(addr, end - addr, ops,
- op_index, last_op, mmu,
- &flush, do_ops);
+ ret = add_munmap(addr, end - addr, ops,
+ &op_index, last_op, mmu,
+ &flush, do_ops);
pgd_mkuptodate(*npgd);
}
addr = end;
@@ -162,9 +165,9 @@
if(end > end_addr)
end = end_addr;
if(force || pud_newpage(*npud)){
- op_index = add_munmap(addr, end - addr, ops,
- op_index, last_op, mmu,
- &flush, do_ops);
+ ret = add_munmap(addr, end - addr, ops,
+ &op_index, last_op, mmu,
+ &flush, do_ops);
pud_mkuptodate(*npud);
}
addr = end;
@@ -177,9 +180,9 @@
if(end > end_addr)
end = end_addr;
if(force || pmd_newpage(*npmd)){
- op_index = add_munmap(addr, end - addr, ops,
- op_index, last_op, mmu,
- &flush, do_ops);
+ ret = add_munmap(addr, end - addr, ops,
+ &op_index, last_op, mmu,
+ &flush, do_ops);
pmd_mkuptodate(*npmd);
}
addr = end;
@@ -198,24 +201,32 @@
}
if(force || pte_newpage(*npte)){
if(pte_present(*npte))
- op_index = add_mmap(addr,
- pte_val(*npte) & PAGE_MASK,
- PAGE_SIZE, r, w, x, ops,
- op_index, last_op, mmu,
- &flush, do_ops);
- else op_index = add_munmap(addr, PAGE_SIZE, ops,
- op_index, last_op, mmu,
- &flush, do_ops);
+ ret = add_mmap(addr,
+ pte_val(*npte) & PAGE_MASK,
+ PAGE_SIZE, r, w, x, ops,
+ &op_index, last_op, mmu,
+ &flush, do_ops);
+ else ret = add_munmap(addr, PAGE_SIZE, ops,
+ &op_index, last_op, mmu,
+ &flush, do_ops);
}
else if(pte_newprot(*npte))
- op_index = add_mprotect(addr, PAGE_SIZE, r, w, x, ops,
- op_index, last_op, mmu,
- &flush, do_ops);
+ ret = add_mprotect(addr, PAGE_SIZE, r, w, x, ops,
+ &op_index, last_op, mmu,
+ &flush, do_ops);
*npte = pte_mkuptodate(*npte);
addr += PAGE_SIZE;
}
- flush = (*do_ops)(mmu, ops, op_index, 1, flush);
+
+ if(!ret)
+ ret = (*do_ops)(mmu, ops, op_index, 1, &flush);
+
+ /* This is not an else because ret is modified above */
+ if(ret) {
+ printk("fix_range_common: failed, killing current process\n");
+ force_sig(SIGKILL, current);
+ }
}
int flush_tlb_kernel_range_common(unsigned long start, unsigned long end)