From 07bf731e4b95d7c9ea9dbacd1fc4a041120dfffb Mon Sep 17 00:00:00 2001 From: Bodo Stroesser Date: Sat, 3 Sep 2005 15:57:50 -0700 Subject: [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 Signed-off-by: Jeff Dike Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/um/kernel/tlb.c | 163 +++++++++++++++++++++++++++------------------------ 1 file changed, 87 insertions(+), 76 deletions(-) (limited to 'arch/um/kernel/tlb.c') diff --git a/arch/um/kernel/tlb.c b/arch/um/kernel/tlb.c index 7d914bb6b00..80ed6188e8a 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 @@ void fix_range_common(struct mm_struct *mm, unsigned long start_addr, 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 @@ void fix_range_common(struct mm_struct *mm, unsigned long start_addr, 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 @@ void fix_range_common(struct mm_struct *mm, unsigned long start_addr, 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 @@ void fix_range_common(struct mm_struct *mm, unsigned long start_addr, } 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) -- cgit v1.2.3