On 4/14/20 6:20 AM, gregkh@xxxxxxxxxxxxxxxxxxx wrote:
>
> The patch below does not apply to the 5.4-stable tree.
> If someone wants it applied there, or to any other stable or longterm
> tree, then please email the backport, including the original git commit
> id to <stable@xxxxxxxxxxxxxxx>.
Here's a 5.4 backport.
>From 4ed734b0d0913e566a9d871e15d24eb240f269f7 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@xxxxxxxxx>
Date: Fri, 20 Mar 2020 11:23:41 -0600
Subject: [PATCH] io_uring: honor original task RLIMIT_FSIZE
With the previous fixes for number of files open checking, I added some
debug code to see if we had other spots where we're checking rlimit()
against the async io-wq workers. The only one I found was file size
checking, which we should also honor.
During write and fallocate prep, store the max file size and override
that for the current ask if we're in io-wq worker context.
Cc: stable@xxxxxxxxxxxxxxx # 5.1+
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
diff --git a/fs/io_uring.c b/fs/io_uring.c
index 607edaef5e71..3550dd97ed64 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -331,6 +331,7 @@ struct io_kiocb {
#define REQ_F_ISREG 2048 /* regular file */
#define REQ_F_MUST_PUNT 4096 /* must be punted even for NONBLOCK */
#define REQ_F_TIMEOUT_NOSEQ 8192 /* no timeout sequence */
+ unsigned long fsize;
u64 user_data;
u32 result;
u32 sequence;
@@ -1404,6 +1405,8 @@ static int io_read(struct io_kiocb *req, const struct sqe_submit *s,
size_t iov_count;
ssize_t read_size, ret;
+ req->fsize = rlimit(RLIMIT_FSIZE);
+
ret = io_prep_rw(req, s, force_nonblock);
if (ret)
return ret;
@@ -1513,10 +1516,17 @@ static int io_write(struct io_kiocb *req, const struct sqe_submit *s,
}
kiocb->ki_flags |= IOCB_WRITE;
+ if (!force_nonblock)
+ current->signal->rlim[RLIMIT_FSIZE].rlim_cur = req->fsize;
+
if (file->f_op->write_iter)
ret2 = call_write_iter(file, kiocb, &iter);
else
ret2 = loop_rw_iter(WRITE, file, kiocb, &iter);
+
+ if (!force_nonblock)
+ current->signal->rlim[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
+
if (!force_nonblock || ret2 != -EAGAIN) {
io_rw_done(kiocb, ret2);
} else {
--
Jens Axboe
