From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Sam Bobroff , Michael Ellerman , Sasha Levin Subject: [PATCH 4.9 01/83] powerpc/eeh: Fix possible null deref in eeh_dump_dev_log() Date: Mon, 19 Nov 2018 17:28:27 +0100 Message-Id: <20181119162612.286359705@linuxfoundation.org> In-Reply-To: <20181119162612.046511542@linuxfoundation.org> References: <20181119162612.046511542@linuxfoundation.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sam Bobroff [ Upstream commit f9bc28aedfb5bbd572d2d365f3095c1becd7209b ] If an error occurs during an unplug operation, it's possible for eeh_dump_dev_log() to be called when edev->pdn is null, which currently leads to dereferencing a null pointer. Handle this by skipping the error log for those devices. Signed-off-by: Sam Bobroff Signed-off-by: Michael Ellerman Signed-off-by: Sasha Levin Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/eeh.c | 5 +++++ 1 file changed, 5 insertions(+) --- a/arch/powerpc/kernel/eeh.c +++ b/arch/powerpc/kernel/eeh.c @@ -169,6 +169,11 @@ static size_t eeh_dump_dev_log(struct ee int n = 0, l = 0; char buffer[128]; + if (!pdn) { + pr_warn("EEH: Note: No error log for absent device.\n"); + return 0; + } + n += scnprintf(buf+n, len-n, "%04x:%02x:%02x.%01x\n", edev->phb->global_number, pdn->busno, PCI_SLOT(pdn->devfn), PCI_FUNC(pdn->devfn));