Commit 13770a71 authored by Dan Carpenter's avatar Dan Carpenter Committed by Jens Axboe
Browse files

io_uring: Fix NULL dereference in error in io_sqe_files_register() 



If we hit a "goto out_free;" before the "ctx->file_data" pointer has
been assigned then it leads to a NULL derefence when we call:

	free_fixed_rsrc_data(ctx->file_data);

We can fix this by moving the assignment earlier.

Fixes: 1ad555c6 ("io_uring: create common fixed_rsrc_data allocation routines")
Signed-off-by: default avatarDan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: default avatarPavel Begunkov <asml.silence@gmail.com>
Signed-off-by: default avatarJens Axboe <axboe@kernel.dk>
parent 8b28fdf2

fs/io_uring.c

+1 −1
Original line number Diff line number Diff line
@@ -7865,6 +7865,7 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, 
	file_data = alloc_fixed_rsrc_data(ctx);

	if (!file_data)

		return -ENOMEM;

	ctx->file_data = file_data;



	nr_tables = DIV_ROUND_UP(nr_args, IORING_MAX_FILES_TABLE);

	file_data->table = kcalloc(nr_tables, sizeof(*file_data->table),
@@ -7874,7 +7875,6 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg, 


	if (io_sqe_alloc_file_tables(file_data, nr_tables, nr_args))

		goto out_free;

	ctx->file_data = file_data;



	for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {

		struct fixed_rsrc_table *table;