From: Sasha Levin <sasha.levin@oracle.com>
To: koverstreet@google.com, akpm@linux-foundation.org
Cc: tytso@mit.edu, viro@zeniv.linux.org.uk, bcrl@kvack.org,
linux-aio@kvack.org, linux-fsdevel@vger.kernel.org,
linux-kernel@vger.kernel.org,
Sasha Levin <sasha.levin@oracle.com>
Subject: [PATCH] fs: aio: use correct integer overflow checks when creation aio ctx
Date: Fri, 17 May 2013 14:23:54 -0400 [thread overview]
Message-ID: <1368815034-844-1-git-send-email-sasha.levin@oracle.com> (raw)
Commit "aio: percpu reqs_available" added some math to the nr_requests
calculation, but didn't correct the overflow calculations to handle that.
This means that this:
#include <linux/aio_abi.h>
void main(void)
{
aio_context_t ctx_idp;
io_setup(0x80000001, &ctx_idp);
}
Would trigger the newly added BUG() couple of lines after the overflow
checks.
Signed-off-by: Sasha Levin <sasha.levin@oracle.com>
---
fs/aio.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/fs/aio.c b/fs/aio.c
index 5b7ed78..0ae450a 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -411,7 +411,8 @@ static struct kioctx *ioctx_alloc(unsigned nr_events)
/* Prevent overflows */
if ((nr_events > (0x10000000U / sizeof(struct io_event))) ||
- (nr_events > (0x10000000U / sizeof(struct kiocb)))) {
+ (nr_events > (0x10000000U / sizeof(struct kiocb))) ||
+ (nr_events < num_possible_cpus() * 4)) {
pr_debug("ENOMEM: nr_events too high\n");
return ERR_PTR(-EINVAL);
}
--
1.8.2.1
--
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next reply other threads:[~2013-05-17 18:23 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-05-17 18:23 Sasha Levin [this message]
2013-05-17 18:53 ` [PATCH] fs: aio: use correct integer overflow checks when creation aio ctx Benjamin LaHaise
2013-05-17 19:05 ` Sasha Levin
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