Messages in this thread | | | From | Andreas Schwab <> | Subject | Re: [PATCH] riscv: reject invalid syscalls below -1 | Date | Wed, 18 Dec 2019 11:35:26 +0100 |
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On Dez 18 2019, David Abdurachmanov wrote:
> On Wed, Dec 18, 2019 at 11:46 AM Andreas Schwab <schwab@suse.de> wrote: >> >> On Dez 18 2019, David Abdurachmanov wrote: >> >> > diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S >> > index a1349ca64669..e163b7b64c86 100644 >> > --- a/arch/riscv/kernel/entry.S >> > +++ b/arch/riscv/kernel/entry.S >> > @@ -246,6 +246,7 @@ check_syscall_nr: >> > */ >> > li t1, -1 >> > beq a7, t1, ret_from_syscall_rejected >> > + blt a7, t1, 1f >> >> How about using bgeu instead in the preceding check? > > The syscall number could be -1 if tracer rejected it.
So check for -1 first, then for out-of-range?
Andreas.
-- Andreas Schwab, SUSE Labs, schwab@suse.de GPG Key fingerprint = 0196 BAD8 1CE9 1970 F4BE 1748 E4D4 88E3 0EEA B9D7 "And now for something completely different."
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