io_uring: Fix memory leak in io_sqe_buffers_register()

unreferenced object 0xffff8881123bf0a0 (size 32):
comm "syz-executor557", pid 8384, jiffies 4294946143 (age 12.360s)
backtrace:
[<ffffffff81469b71>] kmalloc_node include/linux/slab.h:579 [inline]
[<ffffffff81469b71>] kvmalloc_node+0x61/0xf0 mm/util.c:587
[<ffffffff815f0b3f>] kvmalloc include/linux/mm.h:795 [inline]
[<ffffffff815f0b3f>] kvmalloc_array include/linux/mm.h:813 [inline]
[<ffffffff815f0b3f>] kvcalloc include/linux/mm.h:818 [inline]
[<ffffffff815f0b3f>] io_rsrc_data_alloc+0x4f/0xc0 fs/io_uring.c:7164
[<ffffffff815f26d8>] io_sqe_buffers_register+0x98/0x3d0 fs/io_uring.c:8383
[<ffffffff815f84a7>] __io_uring_register+0xf67/0x18c0 fs/io_uring.c:9986
[<ffffffff81609222>] __do_sys_io_uring_register fs/io_uring.c:10091 [inline]
[<ffffffff81609222>] __se_sys_io_uring_register fs/io_uring.c:10071 [inline]
[<ffffffff81609222>] __x64_sys_io_uring_register+0x112/0x230 fs/io_uring.c:10071
[<ffffffff842f616a>] do_syscall_64+0x3a/0xb0 arch/x86/entry/common.c:47
[<ffffffff84400068>] entry_SYSCALL_64_after_hwframe+0x44/0xae

Fix data->tags memory leak, through io_rsrc_data_free() to release
data memory space.

Reported-by: syzbot+0f32d05d8b6cd8d7ea3e@syzkaller.appspotmail.com
Signed-off-by: Zqiang <qiang.zhang@windriver.com>
Link: https://lore.kernel.org/r/20210430082515.13886-1-qiang.zhang@windriver.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Zqiang 2021-04-30 16:25:15 +08:00 committed by Jens Axboe
parent cf3770e784
commit bb6659cc0a

View File

@ -8140,7 +8140,7 @@ static void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
for (i = 0; i < ctx->nr_user_bufs; i++) for (i = 0; i < ctx->nr_user_bufs; i++)
io_buffer_unmap(ctx, &ctx->user_bufs[i]); io_buffer_unmap(ctx, &ctx->user_bufs[i]);
kfree(ctx->user_bufs); kfree(ctx->user_bufs);
kfree(ctx->buf_data); io_rsrc_data_free(ctx->buf_data);
ctx->user_bufs = NULL; ctx->user_bufs = NULL;
ctx->buf_data = NULL; ctx->buf_data = NULL;
ctx->nr_user_bufs = 0; ctx->nr_user_bufs = 0;
@ -8400,7 +8400,7 @@ static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
return -ENOMEM; return -ENOMEM;
ret = io_buffers_map_alloc(ctx, nr_args); ret = io_buffers_map_alloc(ctx, nr_args);
if (ret) { if (ret) {
kfree(data); io_rsrc_data_free(data);
return ret; return ret;
} }