[PATCH 2/4] io_uring: verify that resv2 is 0 in io_uring_rsrc_update2

From: Dylan Yudaken
Date: Tue Apr 12 2022 - 12:31:36 EST


Verify that the user does not pass in anything but 0 for this field.

Fixes: 992da01aa932 ("io_uring: change registration/upd/rsrc tagging ABI")
Signed-off-by: Dylan Yudaken <dylany@xxxxxx>
---
fs/io_uring.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 58bfa71fe3b6..e899192ffb77 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -6839,6 +6839,7 @@ static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
up.nr = 0;
up.tags = 0;
up.resv = 0;
+ up.resv2 = 0;

io_ring_submit_lock(ctx, needs_lock);
ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE,
@@ -11423,7 +11424,7 @@ static int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
memset(&up, 0, sizeof(up));
if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update)))
return -EFAULT;
- if (up.resv)
+ if (up.resv || up.resv2)
return -EINVAL;
return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args);
}
@@ -11437,7 +11438,7 @@ static int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
return -EINVAL;
if (copy_from_user(&up, arg, sizeof(up)))
return -EFAULT;
- if (!up.nr || up.resv)
+ if (!up.nr || up.resv || up.resv2)
return -EINVAL;
return __io_register_rsrc_update(ctx, type, &up, up.nr);
}
--
2.30.2