This is a note to let you know that I've just added the patch titled
fs/aio: Check IOCB_AIO_RW before the struct aio_kiocb conversion
to the 5.15-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
fs-aio-check-iocb_aio_rw-before-the-struct-aio_kiocb-conversion.patch
and it can be found in the queue-5.15 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From 961ebd120565cb60cebe21cb634fbc456022db4a Mon Sep 17 00:00:00 2001
From: Bart Van Assche <bvanassche@xxxxxxx>
Date: Mon, 4 Mar 2024 15:57:15 -0800
Subject: fs/aio: Check IOCB_AIO_RW before the struct aio_kiocb conversion
From: Bart Van Assche <bvanassche@xxxxxxx>
commit 961ebd120565cb60cebe21cb634fbc456022db4a upstream.
The first kiocb_set_cancel_fn() argument may point at a struct kiocb
that is not embedded inside struct aio_kiocb. With the current code,
depending on the compiler, the req->ki_ctx read happens either before
the IOCB_AIO_RW test or after that test. Move the req->ki_ctx read such
that it is guaranteed that the IOCB_AIO_RW test happens first.
Reported-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Cc: Benjamin LaHaise <ben@xxxxxxxxxxxxxxxxx>
Cc: Eric Biggers <ebiggers@xxxxxxxxxx>
Cc: Christoph Hellwig <hch@xxxxxx>
Cc: Avi Kivity <avi@xxxxxxxxxxxx>
Cc: Sandeep Dhavale <dhavale@xxxxxxxxxx>
Cc: Jens Axboe <axboe@xxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: Kent Overstreet <kent.overstreet@xxxxxxxxx>
Cc: stable@xxxxxxxxxxxxxxx
Fixes: b820de741ae4 ("fs/aio: Restrict kiocb_set_cancel_fn() to I/O submitted via libaio")
Signed-off-by: Bart Van Assche <bvanassche@xxxxxxx>
Link: https://lore.kernel.org/r/20240304235715.3790858-1-bvanassche@xxxxxxx
Reviewed-by: Jens Axboe <axboe@xxxxxxxxx>
Reviewed-by: Eric Biggers <ebiggers@xxxxxxxxxx>
Signed-off-by: Christian Brauner <brauner@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/aio.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -564,8 +564,8 @@ static int aio_setup_ring(struct kioctx
void kiocb_set_cancel_fn(struct kiocb *iocb, kiocb_cancel_fn *cancel)
{
- struct aio_kiocb *req = container_of(iocb, struct aio_kiocb, rw);
- struct kioctx *ctx = req->ki_ctx;
+ struct aio_kiocb *req;
+ struct kioctx *ctx;
unsigned long flags;
/*
@@ -575,9 +575,13 @@ void kiocb_set_cancel_fn(struct kiocb *i
if (!(iocb->ki_flags & IOCB_AIO_RW))
return;
+ req = container_of(iocb, struct aio_kiocb, rw);
+
if (WARN_ON_ONCE(!list_empty(&req->ki_list)))
return;
+ ctx = req->ki_ctx;
+
spin_lock_irqsave(&ctx->ctx_lock, flags);
list_add_tail(&req->ki_list, &ctx->active_reqs);
req->ki_cancel = cancel;
Patches currently in stable-queue which might be from bvanassche@xxxxxxx are
queue-5.15/fs-aio-check-iocb_aio_rw-before-the-struct-aio_kiocb-conversion.patch
