How does a Yashar's virtue save him?
R. Yonah: I explained (3) that a Yashar recognizes straightness, and chooses and loves straightness. Amidst love, he will bear every hardship that straightness obligates him to bear. He submits to Emes. The verse teaches that his virtue will save him from damage that comes from bearing Emes.
Malbim: A Yashar does not need Tzedek to straighten his path, like a Tamim does. His path is straight by nature, like I explained above (3). However, the act of Tzedek will save him traps and evils of the time.
What is the meaning of "uv'Havas Bogedim Yilachedu"?
Rashi: The verse should be re-arranged - u'Vogedim b'Havas Yilachedu (traitors will be trapped in the breakage that they prepared for others - Metzudas David). R. Yonah #2 - Boged is the opposite of Midas ha'Yashar - "Kofer la'Tzadik Rasha v'Sachas Yesharim Boged" (21:18). Also a Rasha is the opposite of Yashar - "b'Virkas Yesharim Tarum Kares uv'Fi Resha'im Tehares" (11:11). However, when the verse comes to put a Midah opposite a Midah, it puts Boged opposite Yashar, and Rasha opposite Tzadik.
R. Yonah #1: Traitors who are helped via Sheker, will be caught in their Havah. uv'Havas is like uv'Havah. Similarly, "Ir Tehilas" (Yirmeyah 49:25) is like Ir Tehilah.
Malbim: Bogedim are trapped in breakage and evils of the time. Yesharim are saved in the merit of acts of Tzedek.