summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorBenjamin LaHaise <bcrl@kvack.org>2014-06-24 13:12:55 -0400
committerBenjamin LaHaise <bcrl@kvack.org>2014-06-24 13:32:27 -0400
commitf8567a3845ac05bb28f3c1b478ef752762bd39ef (patch)
tree2b84f49db85647fc69e7e00f41281ef3101a6fd8
parent8b8f5d9715845f9ae2b89ce406e71877965b29ca (diff)
downloadop-kernel-dev-f8567a3845ac05bb28f3c1b478ef752762bd39ef.zip
op-kernel-dev-f8567a3845ac05bb28f3c1b478ef752762bd39ef.tar.gz
aio: fix aio request leak when events are reaped by userspace
The aio cleanups and optimizations by kmo that were merged into the 3.10 tree added a regression for userspace event reaping. Specifically, the reference counts are not decremented if the event is reaped in userspace, leading to the application being unable to submit further aio requests. This patch applies to 3.12+. A separate backport is required for 3.10/3.11. This issue was uncovered as part of CVE-2014-0206. Signed-off-by: Benjamin LaHaise <bcrl@kvack.org> Cc: stable@vger.kernel.org Cc: Kent Overstreet <kmo@daterainc.com> Cc: Mateusz Guzik <mguzik@redhat.com> Cc: Petr Matousek <pmatouse@redhat.com>
-rw-r--r--fs/aio.c3
1 files changed, 1 insertions, 2 deletions
diff --git a/fs/aio.c b/fs/aio.c
index 4f078c0..6a9c7e4 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -1021,6 +1021,7 @@ void aio_complete(struct kiocb *iocb, long res, long res2)
/* everything turned out well, dispose of the aiocb. */
kiocb_free(iocb);
+ put_reqs_available(ctx, 1);
/*
* We have to order our ring_info tail store above and test
@@ -1100,8 +1101,6 @@ static long aio_read_events_ring(struct kioctx *ctx,
flush_dcache_page(ctx->ring_pages[0]);
pr_debug("%li h%u t%u\n", ret, head, tail);
-
- put_reqs_available(ctx, ret);
out:
mutex_unlock(&ctx->ring_lock);
OpenPOWER on IntegriCloud