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Add BTI exceptions
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Authored by andrew on Apr 6 2023, 4:09 PM.
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Details

Summary

We could hit these when executing code marked as using BTI but jumps
to a non-branch target instruction.

Sponsored by: Arm Ltd
Sponsored by: The FreeBSD Foundation

Diff Detail

Repository
rG FreeBSD src repository
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Unit
Tests Not Applicable

Event Timeline

sys/arm64/arm64/trap.c
708

it's too bad there's not something like ILL_ILLBRANCH or such, but it looks like ILL_ILLOPC is consistent with Linux

sys/arm64/arm64/trap.c
708

Nothing prevents us from adding specific si_value if it is useful.

This looks good to me... Will have to remember to check qemu's bsd-user to add this.

sys/arm64/arm64/trap.c
708

We set si_trapno to the exception number if userspace needs to know it's a BTI exception.

This revision was not accepted when it landed; it landed in state Needs Review.Sep 22 2023, 5:17 PM
Closed by commit rG450f731b7f23: Add BTI exceptions (authored by andrew). · Explain Why
This revision was automatically updated to reflect the committed changes.