server: Avoid writing out of bounds in get_selector_entry().

Fixes c6dfce2723.

Signed-off-by: Matteo Bruni <mbruni@codeweavers.com>
Signed-off-by: Alexandre Julliard <julliard@winehq.org>
This commit is contained in:
Matteo Bruni 2018-02-16 00:47:55 +01:00 committed by Alexandre Julliard
parent 4477231ab1
commit 1f006f075d
1 changed files with 26 additions and 13 deletions

View File

@ -289,7 +289,7 @@ static int suspend_for_ptrace( struct thread *thread )
}
/* read a long from a thread address space */
static long read_thread_long( struct thread *thread, long *addr, long *data )
static int read_thread_long( struct thread *thread, void *addr, unsigned long *data )
{
errno = 0;
*data = ptrace( PTRACE_PEEKDATA, get_ptrace_pid(thread), (caddr_t)addr, 0 );
@ -301,14 +301,26 @@ static long read_thread_long( struct thread *thread, long *addr, long *data )
return 0;
}
/* write a long to a thread address space */
static long write_thread_long( struct thread *thread, long *addr, long data, unsigned long mask )
static int read_thread_int( struct thread *thread, void *addr, unsigned int *data )
{
long res;
unsigned long long_data;
int ret;
ret = read_thread_long( thread, addr, &long_data );
*data = long_data;
return ret;
}
/* write a long to a thread address space */
static long write_thread_long( struct thread *thread, void *addr, unsigned long data, unsigned long mask )
{
unsigned long old_data;
int res;
if (mask != ~0ul)
{
if (read_thread_long( thread, addr, &res ) == -1) return -1;
data = (data & mask) | (res & ~mask);
if (read_thread_long( thread, addr, &old_data ) == -1) return -1;
data = (data & mask) | (old_data & ~mask);
}
if ((res = ptrace( PTRACE_POKEDATA, get_ptrace_pid(thread), (caddr_t)addr, data )) == -1)
file_set_error();
@ -333,7 +345,7 @@ int read_process_memory( struct process *process, client_ptr_t ptr, data_size_t
{
struct thread *thread = get_ptrace_thread( process );
unsigned int first_offset, last_offset, len;
long data, *addr;
unsigned long data, *addr;
if (!thread) return 0;
@ -347,7 +359,7 @@ int read_process_memory( struct process *process, client_ptr_t ptr, data_size_t
last_offset = (size + first_offset) % sizeof(long);
if (!last_offset) last_offset = sizeof(long);
addr = (long *)(unsigned long)(ptr - first_offset);
addr = (unsigned long *)(unsigned long)(ptr - first_offset);
len = (size + first_offset + sizeof(long) - 1) / sizeof(long);
if (suspend_for_ptrace( thread ))
@ -517,13 +529,14 @@ void get_selector_entry( struct thread *thread, int entry, unsigned int *base,
}
if (suspend_for_ptrace( thread ))
{
unsigned char flags_buf[4];
unsigned int flags_buf;
unsigned long addr = (unsigned long)thread->process->ldt_copy + (entry * 4);
if (read_thread_long( thread, (long *)addr, (long *)base ) == -1) goto done;
if (read_thread_long( thread, (long *)(addr + (8192 * 4)), (long *)limit ) == -1) goto done;
if (read_thread_int( thread, (void *)addr, base ) == -1) goto done;
if (read_thread_int( thread, (void *)(addr + (8192 * 4)), limit ) == -1) goto done;
addr = (unsigned long)thread->process->ldt_copy + (2 * 8192 * 4) + (entry & ~3);
if (read_thread_long( thread, (long *)addr, (long *)flags_buf ) == -1) goto done;
*flags = flags_buf[entry % 4];
if (read_thread_int( thread, (void *)addr, &flags_buf ) == -1) goto done;
*flags = flags_buf >> (entry & 3) * 8;
done:
resume_after_ptrace( thread );
}