io_uring: fix memleak in io_sqe_files_register()
I got a memleak report when doing some fuzz test:
BUG: memory leak
unreferenced object 0x607eeac06e78 (size 8):
comm "test", pid 295, jiffies 4294735835 (age 31.745s)
hex dump (first 8 bytes):
00 00 00 00 00 00 00 00 ........
backtrace:
[<00000000932632e6>] percpu_ref_init+0x2a/0x1b0
[<0000000092ddb796>] __io_uring_register+0x111d/0x22a0
[<00000000eadd6c77>] __x64_sys_io_uring_register+0x17b/0x480
[<00000000591b89a6>] do_syscall_64+0x56/0xa0
[<00000000864a281d>] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Call percpu_ref_exit() on error path to avoid
refcount memleak.
Fixes: 05f3fb3c5397 ("io_uring: avoid ring quiesce for fixed file set unregister and update")
Cc: stable@vger.kernel.org
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/fs/io_uring.c b/fs/io_uring.c
index a9ce2e6..fc07baf 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -6699,6 +6699,7 @@ static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
for (i = 0; i < nr_tables; i++)
kfree(ctx->file_data->table[i].files);
+ percpu_ref_exit(&ctx->file_data->refs);
kfree(ctx->file_data->table);
kfree(ctx->file_data);
ctx->file_data = NULL;