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 E6E532EC027; Mon, 5 May 2025 22:22:56 +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=1746483777; cv=none; b=u1GcKv8j95rPcoNu9ubPxe2Js5bhkatZhSwsnHE6KpKeBW21FlOAVY/ZBx16gi/F6iRIYGPm5juV7fYOk0L/RGb/ZfUQAfmpEW1cz5Jnnt9ANmR/B3I369V5M/W55D5DtW7TMMIxNJn2GQBPXAlznaO2XnywejOqKvi+Qnfk7Eg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1746483777; c=relaxed/simple; bh=xH85xPGyFvNEPB2DspZSW0SjwYfEHvEu14y6gt6Dme0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version:Content-Type; b=gwnCugBLSZZVVYO8hB3Lf7be5jGoOWvDlYvCdibtQsB0CBrusaJur/qpwi99brOo+Yl3Ni9N9Vv16Qq8n7Krj7rczhLbXcALBGtLyl/LvRl5jDUu3oPwr2BIlXRC9t110iRrO2JWJC+Yf40+x6BcV9eOjA6/w1D5ddN8NLAfjyw= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=FtcsRP45; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="FtcsRP45" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 81DB3C4CEE4; Mon, 5 May 2025 22:22:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1746483776; bh=xH85xPGyFvNEPB2DspZSW0SjwYfEHvEu14y6gt6Dme0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=FtcsRP45tA5sebP/9W4bmUetxbYPf1dNimx2QDmE22/h1blTLoUtgGF8X4wk9ASNu 1MWlfzDh2UzfZuuQvJ0almCYU4/603+TtFqFW5/18djk2vT2/xgQFJqYdWHVIctQqE p6MLPrmUa1Y0tX3MZumUiWnJ4HhYohc97DxXndHfeI8HkAmkg+xByOgrJBo85Z81Sc pVEX5KWLgLJT54jXHL6thYK3j6/2LnAE91zlJNgLw0Fp/1pfGwYlxrvAIaXDcb00O5 aa2VxapiOUbuy6aYg76A1r14bvmrSWnwrpHE4+7zfIYVjMOLcnyT/giSF6hdP2OryO T4n7cK+xIPVIQ== From: Sasha Levin To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Christian Bruel , Niklas Cassel , Manivannan Sadhasivam , =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= , Sasha Levin , kw@linux.com, bhelgaas@google.com, Frank.Li@nxp.com, dlemoal@kernel.org, linux-pci@vger.kernel.org Subject: [PATCH AUTOSEL 6.14 213/642] PCI: endpoint: pci-epf-test: Fix double free that causes kernel to oops Date: Mon, 5 May 2025 18:07:09 -0400 Message-Id: <20250505221419.2672473-213-sashal@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250505221419.2672473-1-sashal@kernel.org> References: <20250505221419.2672473-1-sashal@kernel.org> Precedence: bulk X-Mailing-List: linux-pci@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-stable: review X-Patchwork-Hint: Ignore X-stable-base: Linux 6.14.5 Content-Transfer-Encoding: 8bit From: Christian Bruel [ Upstream commit 934e9d137d937706004c325fa1474f9e3f1ba10a ] Fix a kernel oops found while testing the stm32_pcie Endpoint driver with handling of PERST# deassertion: During EP initialization, pci_epf_test_alloc_space() allocates all BARs, which are further freed if epc_set_bar() fails (for instance, due to no free inbound window). However, when pci_epc_set_bar() fails, the error path: pci_epc_set_bar() -> pci_epf_free_space() does not clear the previous assignment to epf_test->reg[bar]. Then, if the host reboots, the PERST# deassertion restarts the BAR allocation sequence with the same allocation failure (no free inbound window), creating a double free situation since epf_test->reg[bar] was deallocated and is still non-NULL. Thus, make sure that pci_epf_alloc_space() and pci_epf_free_space() invocations are symmetric, and as such, set epf_test->reg[bar] to NULL when memory is freed. Reviewed-by: Niklas Cassel Reviewed-by: Manivannan Sadhasivam Signed-off-by: Christian Bruel Link: https://lore.kernel.org/r/20250124123043.96112-1-christian.bruel@foss.st.com [kwilczynski: commit log] Signed-off-by: Krzysztof Wilczyński Signed-off-by: Sasha Levin --- drivers/pci/endpoint/functions/pci-epf-test.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/pci/endpoint/functions/pci-epf-test.c b/drivers/pci/endpoint/functions/pci-epf-test.c index 2409787cf56d9..bce3ae2c0f652 100644 --- a/drivers/pci/endpoint/functions/pci-epf-test.c +++ b/drivers/pci/endpoint/functions/pci-epf-test.c @@ -738,6 +738,7 @@ static int pci_epf_test_set_bar(struct pci_epf *epf) if (ret) { pci_epf_free_space(epf, epf_test->reg[bar], bar, PRIMARY_INTERFACE); + epf_test->reg[bar] = NULL; dev_err(dev, "Failed to set BAR%d\n", bar); if (bar == test_reg_bar) return ret; @@ -929,6 +930,7 @@ static void pci_epf_test_free_space(struct pci_epf *epf) pci_epf_free_space(epf, epf_test->reg[bar], bar, PRIMARY_INTERFACE); + epf_test->reg[bar] = NULL; } } -- 2.39.5