LGTM Reviewed-by: Yang Erkun <yangerkun@xxxxxxxxxx> 在 2024/11/9 6:13, trondmy@xxxxxxxxxx 写道:
From: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> Yang Erkun reports that when two threads are opening files at the same time, and are forced to abort before a reply is seen, then the call to nfs_release_seqid() in nfs4_opendata_free() can result in a use-after-free of the pointer to the defunct rpc task of the other thread. The fix is to ensure that if the RPC call is aborted before the call to nfs_wait_on_sequence() is complete, then we must call nfs_release_seqid() in nfs4_open_release() before the rpc_task is freed. Reported-by: Yang Erkun <yangerkun@xxxxxxxxxx> Fixes: 24ac23ab88df ("NFSv4: Convert open() into an asynchronous RPC call") Signed-off-by: Trond Myklebust <trond.myklebust@xxxxxxxxxxxxxxx> --- fs/nfs/nfs4proc.c | 8 +++++--- 1 file changed, 5 insertions(+), 3 deletions(-) diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 9d40319e063d..405f17e6e0b4 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -2603,12 +2603,14 @@ static void nfs4_open_release(void *calldata) struct nfs4_opendata *data = calldata; struct nfs4_state *state = NULL;+ /* In case of error, no cleanup! */+ if (data->rpc_status != 0 || !data->rpc_done) { + nfs_release_seqid(data->o_arg.seqid); + goto out_free; + } /* If this request hasn't been cancelled, do nothing */ if (!data->cancelled) goto out_free; - /* In case of error, no cleanup! */ - if (data->rpc_status != 0 || !data->rpc_done) - goto out_free; /* In case we need an open_confirm, no cleanup! */ if (data->o_res.rflags & NFS4_OPEN_RESULT_CONFIRM) goto out_free;
