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aio: Fix up the opcode in aiocb32_copyin()
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Authored by markj on Sep 11 2021, 4:24 PM.

Details

Summary

With lio_listio(2), the opcode is specified by userspace rather than
being hard-coded by the system call (e.g., aio_readv() -> LIO_READV).
kern_lio_listio() calls aio_aqueue() with an opcode of LIO_NOP, which
gets fixed up when the aiocb is copied in.

When copying in a job request, we need to dynamically allocate a uio to
wrap the iovec. So aiocb_copyin() needs to get the opcode from the
aiocb and then decide whether an allocation is required. We failed to
do this in the COMPAT_FREEBSD32 case. Fix it.

Reported by: syzbot+27eab6f2c2162f2885ee@syzkaller.appspotmail.com
Fixes: f30a1ae8d529 ("lio_listio(2): Allow LIO_READV and LIO_WRITEV.")

Diff Detail

Repository
rS FreeBSD src repository - subversion
Lint
Lint OK
Unit
No Unit Test Coverage
Build Status
Buildable 41468
Build 38357: arc lint + arc unit

Event Timeline

markj requested review of this revision.Sep 11 2021, 4:24 PM

Good catch. Too bad I hadn't gotten around to adding aio_writev support to Nix, or its test suite would've caught this.

This revision is now accepted and ready to land.Sep 11 2021, 4:38 PM
This revision was automatically updated to reflect the committed changes.