xnu-1228.15.4.tar.gz

[apple/xnu.git] / bsd / dev / dtrace / dtrace_glue.c

diff --git a/bsd/dev/dtrace/dtrace_glue.c b/bsd/dev/dtrace/dtrace_glue.c
index 035150aa799f0a0fd5511737813161d8a06cbd5d..1ef883569ca730ec83c5b8634272a28e6380f015 100644 (file)
--- a/bsd/dev/dtrace/dtrace_glue.c
+++ b/bsd/dev/dtrace/dtrace_glue.c
@@ -1218,7 +1218,16 @@ dtrace_copyinstr(user_addr_t src, uintptr_t dst, size_t len)
        size_t actual;
        
        if (dtrace_copycheck( src, dst, len )) {
-               if (copyinstr((const user_addr_t)src, (char *)dst, (vm_size_t)len, &actual)) {
+               /*  copyin as many as 'len' bytes. */
+               int error = copyinstr((const user_addr_t)src, (char *)dst, (vm_size_t)len, &actual);
+
+               /*
+                * ENAMETOOLONG is returned when 'len' bytes have been copied in but the NUL terminator was
+                * not encountered. That does not require raising CPU_DTRACE_BADADDR, and we press on.
+                * Note that we do *not* stuff a NUL terminator when returning ENAMETOOLONG, that's left
+                * to the caller.
+                */
+               if (error && error != ENAMETOOLONG) {
                        DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
                        cpu_core[CPU->cpu_id].cpuc_dtrace_illval = src;
                }
@@ -1244,6 +1253,13 @@ dtrace_copyoutstr(uintptr_t src, user_addr_t dst, size_t len)
        size_t actual;
 
        if (dtrace_copycheck( dst, src, len )) {
+
+               /*
+                * ENAMETOOLONG is returned when 'len' bytes have been copied out but the NUL terminator was
+                * not encountered. We raise CPU_DTRACE_BADADDR in that case.
+                * Note that we do *not* stuff a NUL terminator when returning ENAMETOOLONG, that's left
+                * to the caller.
+                */
                if (copyoutstr((const void *)src, dst, (size_t)len, &actual)) {
                        DTRACE_CPUFLAG_SET(CPU_DTRACE_BADADDR);
                        cpu_core[CPU->cpu_id].cpuc_dtrace_illval = dst;