From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793214249; b=uIIsWNHByS8yJBd+PY+hJ0CW7EGLZBVreeCX3kQaKTXuF2xB7iom5x2bKnIJh3Tes4dn UUbX/gTpSMGKlnloorb7DKsM4QiKjfHVx3W9gPoXhnTVjo2zbVTPsDws75fa41uCaiwn/ gXS1OhPxGqwSbOKM27FtXBg7GOk1SiuhVGmzZuRdxAWnlBWzSLzFZwebLVIsVWkp1Hkrh i4D4SF56OEzv08nSg0U8wm6bs0+lUCQvye2oGjbcvsQJwVykmIO34ZzPyckHGn6NMxL69 FVFLANQGeCvXCPDmJNA/xqGgdZwtuE/vOljoMWMTsM1yHYTgvb9Igip0wqhHISxXa9w== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793214249; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Type:Content-Transfer-Encoding; bh=mbpEZ7r+3VJfx2vWIfbPb0oOoe//QqS8nfUj3OHF+sI=; b=B+tuF0Co2ltcfIWCcxyBw9auj4YuBDADkYHFgOejBXex9T3iFlM+YPV8hIalVBWip+ST QuXx86PIxc/iAZvPAoVWKoPFvBZXMciqxSkP04NThrk0XvVtH/6a3M1Ch63DuSP63ume4 HoJ+GOmbbWBihUB53OeYuKaHbZepahNrzOS9jATsoxB6UAXrTbMuRGsx8PLkiEQoaXcJZ US10lucqAAMOqH+GFsBJJyFXwVLrD/SstQm1lQ0IGkFlqFJCq6HI/AXUr3ST/TRZb6f5B BJSgebRZ9KZovGzEe5vImW3gdjPmuwUSPhB1PdMfdpXRmM0gD38tSp/vjv1SLVgcq8w== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Fsj+tWUa; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 9D434606A31D; Wed, 28 Oct 2026 19:04:09 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=Fsj+tWUa Received: by smtp.kernel.org (Postfix) with ESMTPSA id EBD0B1F01829; Wed, 28 Oct 2026 19:04:08 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793214249; bh=mbpEZ7r+3VJfx2vWIfbPb0oOoe//QqS8nfUj3OHF+sI=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=Fsj+tWUaslqL18PvLaKDeZcrQnyLO2RanlFRnoxlmoiS6aT5sc1amauWOl66v9HPI lv42MY5w9kk24VbsdE+Pc2a9utvkZY4LBdLCNTwcfCV5LUXMXP6JJ84OHRacj+h3Q2 O2jyIT4wnSD0KBucDmIvRZrlpkWMuLziX6tiak+Y= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Niklas Cassel , Manivannan Sadhasivam , Christian Bruel , =?UTF-8?q?Krzysztof=20Wilczy=C5=84ski?= , Sasha Levin Subject: [PATCH 6.1 0791/1887] PCI: endpoint: pci-epf-test: Fix double free that causes kernel to oops Date: Wed, 28 Oct 2026 17:48:07 +0100 Message-ID: <20261028170517.433281711@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261028170459.200466217@linuxfoundation.org> References: <20261028170459.200466217@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 6.1-stable review patch. If anyone has any objections, please let me know. ------------------ 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 fb47ce721e095..53f1236cd91d7 100644 --- a/drivers/pci/endpoint/functions/pci-epf-test.c +++ b/drivers/pci/endpoint/functions/pci-epf-test.c @@ -735,6 +735,7 @@ static void pci_epf_test_unbind(struct pci_epf *epf) epf_bar); pci_epf_free_space(epf, epf_test->reg[bar], bar, PRIMARY_INTERFACE); + epf_test->reg[bar] = NULL; } } } @@ -769,6 +770,7 @@ 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; -- 2.53.0