Mercurial > hg > truffle
diff src/share/vm/prims/jvmtiEnvBase.cpp @ 611:2f716c0acb64
6567360: 3/4 SIGBUS in jvmti RawMonitor magic check for unaligned bad monitor pointer
Summary: Change JvmtiEnvBase::is_valid() and JvmtiRawMonitor::is_valid() to fetch the _magic fields via Bytes::get_native_u[248]().
Reviewed-by: coleenp, swamyv
author | dcubed |
---|---|
date | Mon, 02 Mar 2009 14:05:07 -0700 |
parents | ea20d7ce26b0 |
children | b109e761e927 |
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--- a/src/share/vm/prims/jvmtiEnvBase.cpp Mon Mar 02 14:03:03 2009 -0700 +++ b/src/share/vm/prims/jvmtiEnvBase.cpp Mon Mar 02 14:05:07 2009 -0700 @@ -94,6 +94,35 @@ } +bool +JvmtiEnvBase::is_valid() { + jint value = 0; + + // This object might not be a JvmtiEnvBase so we can't assume + // the _magic field is properly aligned. Get the value in a safe + // way and then check against JVMTI_MAGIC. + + switch (sizeof(_magic)) { + case 2: + value = Bytes::get_native_u2((address)&_magic); + break; + + case 4: + value = Bytes::get_native_u4((address)&_magic); + break; + + case 8: + value = Bytes::get_native_u8((address)&_magic); + break; + + default: + guarantee(false, "_magic field is an unexpected size"); + } + + return value == JVMTI_MAGIC; +} + + JvmtiEnvBase::JvmtiEnvBase() : _env_event_enable() { _env_local_storage = NULL; _tag_map = NULL;