mirror of https://github.com/acidanthera/audk.git
d9be0f66ff
REF: https://bugzilla.tianocore.org/show_bug.cgi?id=695 Within function CoreRestoreTpl(), left shift a negative value -2 is used in: "while (((-2 << NewTpl) & gEventPending) != 0) {" which involves undefined behavior. According to the C11 spec, Section 6.5.7: > 4 The result of E1 << E2 is E1 left-shifted E2 bit positions; vacated > bits are filled with zeros. If E1 has an unsigned type, the value > of the result is E1 * 2^E2 , reduced modulo one more than the > maximum value representable in the result type. If E1 has a signed > type and nonnegative value, and E1 * 2^E2 is representable in the > result type, then that is the resulting value; otherwise, the > behavior is undefined. This commit refines the code logic to avoid left shifting the negative value. Cc: Steven Shi <steven.shi@intel.com> Cc: Eric Dong <eric.dong@intel.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Michael Kinney <michael.d.kinney@intel.com> Cc: Liming Gao <liming.gao@intel.com> Contributed-under: TianoCore Contribution Agreement 1.1 Signed-off-by: Hao Wu <hao.a.wu@intel.com> Reviewed-by: Star Zeng <star.zeng@intel.com> |
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| .. | ||
| Event.c | ||
| Event.h | ||
| Timer.c | ||
| Tpl.c | ||