server: Fix pointer arithmetic in get_selector_entry().

The selector table is exclusively 32-bit, so trying to get selector entries with a 64-bit wineserver will return the wrong values due to the different size of (long *). Signed-off-by: Zebediah Figura <z.figura12@gmail.com> Signed-off-by: Alexandre Julliard <julliard@winehq.org>

server: Fix pointer arithmetic in get_selector_entry().
c6dfce27 · Zebediah Figura · Alexandre Julliard · 67d7eb98 · c6dfce27
Commit c6dfce27 authored Feb 10, 2018 by Zebediah Figura Committed by Alexandre Julliard Feb 12, 2018
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ptrace.c server/ptrace.c +7 -7

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--- a/server/ptrace.c
+++ b/server/ptrace.c
@@ -517,13 +517,13 @@ void get_selector_entry( struct thread *thread, int entry, unsigned int *base,
    }
    if (suspend_for_ptrace( thread ))
    {
-        unsigned char flags_buf[sizeof(long)];
-        long *addr = (long *)(unsigned long)thread->process->ldt_copy + entry;
-        if (read_thread_long( thread, addr, (long *)base ) == -1) goto done;
-        if (read_thread_long( thread, addr + 8192, (long *)limit ) == -1) goto done;
-        addr = (long *)(unsigned long)thread->process->ldt_copy + 2*8192 + (entry / sizeof(long));
-        if (read_thread_long( thread, addr, (long *)flags_buf ) == -1) goto done;
-        *flags = flags_buf[entry % sizeof(long)];
+        unsigned char flags_buf[4];
+        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;
+        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];
    done:
        resume_after_ptrace( thread );
    }