2022-04-06 15:42:39

by Eugene Syromiatnikov

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Subject: [PATCH] io_uring: implement compat handling for IORING_REGISTER_IOWQ_AFF

Similarly to the way it is done im mbind syscall.

Cc: [email protected] # 5.14
Fixes: fe76421d1da1dcdb ("io_uring: allow user configurable IO thread CPU affinity")
Signed-off-by: Eugene Syromiatnikov <[email protected]>
---
fs/io_uring.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index de9c9de..83e194f 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -10803,7 +10803,15 @@ static __cold int io_register_iowq_aff(struct io_ring_ctx *ctx,
if (len > cpumask_size())
len = cpumask_size();

- if (copy_from_user(new_mask, arg, len)) {
+ if (in_compat_syscall()) {
+ ret = compat_get_bitmap(cpumask_bits(new_mask),
+ (const compat_ulong_t __user *)arg,
+ len * 8 /* CHAR_BIT */);
+ } else {
+ ret = copy_from_user(new_mask, arg, len);
+ }
+
+ if (ret) {
free_cpumask_var(new_mask);
return -EFAULT;
}
--
2.1.4


2022-04-06 16:30:05

by Jens Axboe

[permalink] [raw]
Subject: Re: [PATCH] io_uring: implement compat handling for IORING_REGISTER_IOWQ_AFF

On 4/6/22 5:55 AM, Eugene Syromiatnikov wrote:
> Similarly to the way it is done im mbind syscall.

Thanks, applied.

--
Jens Axboe