Messages in this thread | | | From | Jeff Moyer <> | Subject | Re: [PATCH] aio: fix io_setup/io_destroy race | Date | Wed, 07 Mar 2012 13:16:18 -0500 |
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Al Viro <viro@ZenIV.linux.org.uk> writes:
> Have ioctx_alloc() return an extra reference, so that caller would drop it > on success and not bother with re-grabbing it on failure exit. The current > code is obviously broken - io_destroy() from another thread that managed > to guess the address io_setup() would've returned would free ioctx right > under us; gets especially interesting if aio_context_t * we pass to > io_setup() points to PROT_READ mapping, so put_user() fails and we end > up doing io_destroy() on kioctx another thread has just got freed...
Al, you certainly are creative. ;-) I agree with the problem and the fix. It would be nice, though if you had added comments.
I ran xfstests ./check -g aio, and there were no problems.
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
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