From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.6 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id C39D3C433E0 for ; Sat, 13 Mar 2021 13:24:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 9A1FD64F19 for ; Sat, 13 Mar 2021 13:24:16 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230309AbhCMNXm (ORCPT ); Sat, 13 Mar 2021 08:23:42 -0500 Received: from forward2-smtp.messagingengine.com ([66.111.4.226]:45041 "EHLO forward2-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233645AbhCMNXc (ORCPT ); Sat, 13 Mar 2021 08:23:32 -0500 Received: from compute4.internal (compute4.nyi.internal [10.202.2.44]) by mailforward.nyi.internal (Postfix) with ESMTP id DDD3A1941D0F; Sat, 13 Mar 2021 08:23:31 -0500 (EST) Received: from mailfrontend2 ([10.202.2.163]) by compute4.internal (MEProxy); Sat, 13 Mar 2021 08:23:31 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=cc:content-transfer-encoding:content-type :date:from:message-id:mime-version:subject:to:x-me-proxy :x-me-proxy:x-me-sender:x-me-sender:x-sasl-enc; s=fm2; bh=L0MwYV jgtpRkyl9Yx7Iyp5FIp53mYOxzIerjtjxolbE=; b=VNQu1TQInV7RKqDgi4q6D4 SDRlaBGqOJXJ3riAiex9Y4vC3i6r1/OElaPqrZOfJSHbbnSgz6/J0vsH1SLo6nDH i3jUW0tiJHypjScHWm0yTZZbvZqw4sEztWh3BIloZ/TV37v8bJVNESVfbwzKjemg DaRPbUbcs+oTNrA672q8O5C4WmlNOqKYW/3/u4rPwzARBu9leJHsdnL9QzKook00 9iBhpdxSuTo16b8/dQEZBpOUnWYuayQmeC1kaOcQs9kO5//yzP+qUAOFOf5v91jO xumf8aRdEV6kTZ/TOu0076olyuBGxNEH88I3eKPTzeBbbiQLPW2k7vVOChphlkUQ == X-ME-Sender: X-ME-Proxy-Cause: gggruggvucftvghtrhhoucdtuddrgeduledruddvgedghedtucetufdoteggodetrfdotf fvucfrrhhofhhilhgvmecuhfgrshhtofgrihhlpdfqfgfvpdfurfetoffkrfgpnffqhgen uceurghilhhouhhtmecufedttdenucenucfjughrpefuvffhfffkgggtgfesthekredttd dtlfenucfhrhhomhepoehgrhgvghhkhheslhhinhhugihfohhunhgurghtihhonhdrohhr gheqnecuggftrfgrthhtvghrnhepkeekuddtveevheejgefghfdvgfekgfegfeduudevtd fggfdvvdethfekffdvveevnecuffhomhgrihhnpehkvghrnhgvlhdrohhrghdplhhishht rdhnvgigthenucfkphepkeefrdekiedrjeegrdeigeenucevlhhushhtvghrufhiiigvpe dunecurfgrrhgrmhepmhgrihhlfhhrohhmpehgrhgvgheskhhrohgrhhdrtghomh X-ME-Proxy: Received: from localhost (83-86-74-64.cable.dynamic.v4.ziggo.nl [83.86.74.64]) by mail.messagingengine.com (Postfix) with ESMTPA id 8B8041080057; Sat, 13 Mar 2021 08:23:31 -0500 (EST) Subject: FAILED: patch "[PATCH] io_uring: Convert personality_idr to XArray" failed to apply to 5.10-stable tree To: willy@infradead.org, asml.silence@gmail.com, axboe@kernel.dk, yangerkun@huawei.com Cc: From: Date: Sat, 13 Mar 2021 14:23:21 +0100 Message-ID: <1615641801225144@kroah.com> MIME-Version: 1.0 Content-Type: text/plain; charset=ANSI_X3.4-1968 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: stable@vger.kernel.org The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to . thanks, greg k-h ------------------ original commit in Linus's tree ------------------ >From 61cf93700fe6359552848ed5e3becba6cd760efa Mon Sep 17 00:00:00 2001 From: "Matthew Wilcox (Oracle)" Date: Mon, 8 Mar 2021 14:16:16 +0000 Subject: [PATCH] io_uring: Convert personality_idr to XArray You can't call idr_remove() from within a idr_for_each() callback, but you can call xa_erase() from an xa_for_each() loop, so switch the entire personality_idr from the IDR to the XArray. This manifests as a use-after-free as idr_for_each() attempts to walk the rest of the node after removing the last entry from it. Fixes: 071698e13ac6 ("io_uring: allow registering credentials") Cc: stable@vger.kernel.org # 5.6+ Reported-by: yangerkun Signed-off-by: Matthew Wilcox (Oracle) [Pavel: rebased (creds load was moved into io_init_req())] Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/7ccff36e1375f2b0ebf73d957f037b43becc0dde.1615212806.git.asml.silence@gmail.com Signed-off-by: Jens Axboe diff --git a/fs/io_uring.c b/fs/io_uring.c index 3f6db813d670..84eb499368a4 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -406,7 +406,8 @@ struct io_ring_ctx { struct idr io_buffer_idr; - struct idr personality_idr; + struct xarray personalities; + u32 pers_next; struct { unsigned cached_cq_tail; @@ -1137,7 +1138,7 @@ static struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p) init_completion(&ctx->ref_comp); init_completion(&ctx->sq_thread_comp); idr_init(&ctx->io_buffer_idr); - idr_init(&ctx->personality_idr); + xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1); mutex_init(&ctx->uring_lock); init_waitqueue_head(&ctx->wait); spin_lock_init(&ctx->completion_lock); @@ -6337,7 +6338,7 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req, req->work.list.next = NULL; personality = READ_ONCE(sqe->personality); if (personality) { - req->work.creds = idr_find(&ctx->personality_idr, personality); + req->work.creds = xa_load(&ctx->personalities, personality); if (!req->work.creds) return -EINVAL; get_cred(req->work.creds); @@ -8355,7 +8356,6 @@ static void io_ring_ctx_free(struct io_ring_ctx *ctx) mutex_unlock(&ctx->uring_lock); io_eventfd_unregister(ctx); io_destroy_buffers(ctx); - idr_destroy(&ctx->personality_idr); #if defined(CONFIG_UNIX) if (ctx->ring_sock) { @@ -8420,7 +8420,7 @@ static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id) { const struct cred *creds; - creds = idr_remove(&ctx->personality_idr, id); + creds = xa_erase(&ctx->personalities, id); if (creds) { put_cred(creds); return 0; @@ -8429,14 +8429,6 @@ static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id) return -EINVAL; } -static int io_remove_personalities(int id, void *p, void *data) -{ - struct io_ring_ctx *ctx = data; - - io_unregister_personality(ctx, id); - return 0; -} - static bool io_run_ctx_fallback(struct io_ring_ctx *ctx) { struct callback_head *work, *next; @@ -8526,13 +8518,17 @@ static void io_ring_exit_work(struct work_struct *work) static void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx) { + unsigned long index; + struct creds *creds; + mutex_lock(&ctx->uring_lock); percpu_ref_kill(&ctx->refs); /* if force is set, the ring is going away. always drop after that */ ctx->cq_overflow_flushed = 1; if (ctx->rings) __io_cqring_overflow_flush(ctx, true, NULL, NULL); - idr_for_each(&ctx->personality_idr, io_remove_personalities, ctx); + xa_for_each(&ctx->personalities, index, creds) + io_unregister_personality(ctx, index); mutex_unlock(&ctx->uring_lock); io_kill_timeouts(ctx, NULL, NULL); @@ -9162,10 +9158,9 @@ SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit, } #ifdef CONFIG_PROC_FS -static int io_uring_show_cred(int id, void *p, void *data) +static int io_uring_show_cred(struct seq_file *m, unsigned int id, + const struct cred *cred) { - const struct cred *cred = p; - struct seq_file *m = data; struct user_namespace *uns = seq_user_ns(m); struct group_info *gi; kernel_cap_t cap; @@ -9233,9 +9228,13 @@ static void __io_uring_show_fdinfo(struct io_ring_ctx *ctx, struct seq_file *m) seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, (unsigned int) buf->len); } - if (has_lock && !idr_is_empty(&ctx->personality_idr)) { + if (has_lock && !xa_empty(&ctx->personalities)) { + unsigned long index; + const struct cred *cred; + seq_printf(m, "Personalities:\n"); - idr_for_each(&ctx->personality_idr, io_uring_show_cred, m); + xa_for_each(&ctx->personalities, index, cred) + io_uring_show_cred(m, index, cred); } seq_printf(m, "PollList:\n"); spin_lock_irq(&ctx->completion_lock); @@ -9564,14 +9563,16 @@ static int io_probe(struct io_ring_ctx *ctx, void __user *arg, unsigned nr_args) static int io_register_personality(struct io_ring_ctx *ctx) { const struct cred *creds; + u32 id; int ret; creds = get_current_cred(); - ret = idr_alloc_cyclic(&ctx->personality_idr, (void *) creds, 1, - USHRT_MAX, GFP_KERNEL); - if (ret < 0) - put_cred(creds); + ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds, + XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL); + if (!ret) + return id; + put_cred(creds); return ret; }