From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6677937C; Tue, 23 Jan 2024 01:09:23 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705972163; cv=none; b=fF+KKTV2JsVrBhj/rBdNiNAYezeUrbnU5up7z3NePfJwZ1kdZL3mujCjZt2ca6ZqqJwwciEsZHameTe0hzH4QJwjCtthCj2n9+6ppwjDCSGmfaoVbdBbNs+YlPYV08J6xzcT0cI2y5ChqvyLezxqilGOV1J/eXPqQAhI1ku3AOg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1705972163; c=relaxed/simple; bh=2AcKw7uRjM6U9qLY25KDNNAluC9QnnMZyqi6c3eyYUA=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=uO0uPNbSztmJdy+S/ghnZlIOXFhpTtHVNlc0pe/L+kjrIXEO5ytSMg2BG0VxLnMp6Yg6C5y8acuf2EwH077Fc6++S/hFPlL3Keh82RA/SZ8qnOZ675t5WufPxSUJqrFTHpNgIqZN9gjFp7vgppsCqLdSGb2VmP2SIxxY7RejI5s= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=AYp5+AHT; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="AYp5+AHT" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 24530C433C7; Tue, 23 Jan 2024 01:09:23 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1705972163; bh=2AcKw7uRjM6U9qLY25KDNNAluC9QnnMZyqi6c3eyYUA=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=AYp5+AHTV0+N1r/XKXIMRN1p1nolqkw0K23s0gpsTgxWXKenjOjZt4xF395fqTlE3 PdKNjNzkC7pltMImYMbpwFLuCMEjA6NKMou4mBcI+SiMdvTnZh1/IihvAmBGC3CWLH wXDf1raKQZG6sH0sJvL6F9qLdbz5i8DKxAkjfXqE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zhenghan Wang , "Matthew Wilcox (Oracle)" , Linus Torvalds , Sasha Levin Subject: [PATCH 5.15 046/374] ida: Fix crash in ida_free when the bitmap is empty Date: Mon, 22 Jan 2024 15:55:02 -0800 Message-ID: <20240122235746.215139538@linuxfoundation.org> X-Mailer: git-send-email 2.43.0 In-Reply-To: <20240122235744.598274724@linuxfoundation.org> References: <20240122235744.598274724@linuxfoundation.org> User-Agent: quilt/0.67 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Matthew Wilcox (Oracle) [ Upstream commit af73483f4e8b6f5c68c9aa63257bdd929a9c194a ] The IDA usually detects double-frees, but that detection failed to consider the case when there are no nearby IDs allocated and so we have a NULL bitmap rather than simply having a clear bit. Add some tests to the test-suite to be sure we don't inadvertently reintroduce this problem. Unfortunately they're quite noisy so include a message to disregard the warnings. Reported-by: Zhenghan Wang Signed-off-by: Matthew Wilcox (Oracle) Signed-off-by: Linus Torvalds Signed-off-by: Sasha Levin --- lib/idr.c | 2 +- lib/test_ida.c | 40 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 41 insertions(+), 1 deletion(-) diff --git a/lib/idr.c b/lib/idr.c index 13f2758c2377..da36054c3ca0 100644 --- a/lib/idr.c +++ b/lib/idr.c @@ -508,7 +508,7 @@ void ida_free(struct ida *ida, unsigned int id) goto delete; xas_store(&xas, xa_mk_value(v)); } else { - if (!test_bit(bit, bitmap->bitmap)) + if (!bitmap || !test_bit(bit, bitmap->bitmap)) goto err; __clear_bit(bit, bitmap->bitmap); xas_set_mark(&xas, XA_FREE_MARK); diff --git a/lib/test_ida.c b/lib/test_ida.c index b06880625961..55105baa19da 100644 --- a/lib/test_ida.c +++ b/lib/test_ida.c @@ -150,6 +150,45 @@ static void ida_check_conv(struct ida *ida) IDA_BUG_ON(ida, !ida_is_empty(ida)); } +/* + * Check various situations where we attempt to free an ID we don't own. + */ +static void ida_check_bad_free(struct ida *ida) +{ + unsigned long i; + + printk("vvv Ignore \"not allocated\" warnings\n"); + /* IDA is empty; all of these will fail */ + ida_free(ida, 0); + for (i = 0; i < 31; i++) + ida_free(ida, 1 << i); + + /* IDA contains a single value entry */ + IDA_BUG_ON(ida, ida_alloc_min(ida, 3, GFP_KERNEL) != 3); + ida_free(ida, 0); + for (i = 0; i < 31; i++) + ida_free(ida, 1 << i); + + /* IDA contains a single bitmap */ + IDA_BUG_ON(ida, ida_alloc_min(ida, 1023, GFP_KERNEL) != 1023); + ida_free(ida, 0); + for (i = 0; i < 31; i++) + ida_free(ida, 1 << i); + + /* IDA contains a tree */ + IDA_BUG_ON(ida, ida_alloc_min(ida, (1 << 20) - 1, GFP_KERNEL) != (1 << 20) - 1); + ida_free(ida, 0); + for (i = 0; i < 31; i++) + ida_free(ida, 1 << i); + printk("^^^ \"not allocated\" warnings over\n"); + + ida_free(ida, 3); + ida_free(ida, 1023); + ida_free(ida, (1 << 20) - 1); + + IDA_BUG_ON(ida, !ida_is_empty(ida)); +} + static DEFINE_IDA(ida); static int ida_checks(void) @@ -162,6 +201,7 @@ static int ida_checks(void) ida_check_leaf(&ida, 1024 * 64); ida_check_max(&ida); ida_check_conv(&ida); + ida_check_bad_free(&ida); printk("IDA: %u of %u tests passed\n", tests_passed, tests_run); return (tests_run != tests_passed) ? 0 : -EINVAL; -- 2.43.0