From: Jens Axboe <axboe@xxxxxxxxx>
commit bd74048108c179cea0ff52979506164c80f29da7 upstream.
If we hit an earlier error path in io_uring_create(), then we will have
accounted memory, but not set ctx->{sq,cq}_entries yet. Then when the
ring is torn down in error, we use those values to unaccount the memory.
Ensure we set the ctx entries before we're able to hit a potential error
path.
Cc: stable@xxxxxxxxxxxxxxx
Reported-by: Tomáš Chaloupka <chalucha@xxxxxxxxx>
Tested-by: Tomáš Chaloupka <chalucha@xxxxxxxxx>
Reviewed-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
Signed-off-by: Jens Axboe <axboe@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
fs/io_uring.c | 6 ++++--
1 file changed, 4 insertions(+), 2 deletions(-)
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -3857,6 +3857,10 @@ static int io_allocate_scq_urings(struct
struct io_rings *rings;
size_t size, sq_array_offset;
+ /* make sure these are sane, as we already accounted them */
+ ctx->sq_entries = p->sq_entries;
+ ctx->cq_entries = p->cq_entries;
+
size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset);
if (size == SIZE_MAX)
return -EOVERFLOW;
@@ -3873,8 +3877,6 @@ static int io_allocate_scq_urings(struct
rings->cq_ring_entries = p->cq_entries;
ctx->sq_mask = rings->sq_ring_mask;
ctx->cq_mask = rings->cq_ring_mask;
- ctx->sq_entries = rings->sq_ring_entries;
- ctx->cq_entries = rings->cq_ring_entries;
size = array_size(sizeof(struct io_uring_sqe), p->sq_entries);
if (size == SIZE_MAX) {
