From: Colin King <colin.king@canonical.com>
To: Jens Axboe <axboe@kernel.dk>,
Pavel Begunkov <asml.silence@gmail.com>,
io-uring@vger.kernel.org
Cc: kernel-janitors@vger.kernel.org, linux-kernel@vger.kernel.org
Subject: [PATCH][next] io_uring: Fix a read of ununitialized pointer tctx
Date: Fri, 3 Sep 2021 12:35:35 +0100 [thread overview]
Message-ID: <20210903113535.11257-1-colin.king@canonical.com> (raw)
From: Colin Ian King <colin.king@canonical.com>
In the unlikely case where ctx->flags & IORING_SETUP_SQPOLL is true
and sqd is NULL the pointer tctx is not assigned a valid value and
can contain a garbage value when it is dereferenced. Fix this by
initializing it to NULL.
Addresses-Coverity: ("Uninitialized pointer read")
Fixes: 9e30726065ea ("io_uring: ensure IORING_REGISTER_IOWQ_MAX_WORKERS works with SQPOLL")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
fs/io_uring.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 132dd38e89ce..843362bebd8c 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -10525,7 +10525,7 @@ static int io_register_iowq_max_workers(struct io_ring_ctx *ctx,
void __user *arg)
{
struct io_sq_data *sqd = NULL;
- struct io_uring_task *tctx;
+ struct io_uring_task *tctx = NULL;
__u32 new_count[2];
int i, ret;
--
2.32.0
next reply other threads:[~2021-09-03 11:35 UTC|newest]
Thread overview: 2+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-09-03 11:35 Colin King [this message]
2021-09-03 12:16 ` [PATCH][next] io_uring: Fix a read of ununitialized pointer tctx Jens Axboe
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