Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1030302AbaGDXgF (ORCPT ); Fri, 4 Jul 2014 19:36:05 -0400 Received: from mail.ispras.ru ([83.149.199.45]:52121 "EHLO mail.ispras.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753689AbaGDXgC (ORCPT ); Fri, 4 Jul 2014 19:36:02 -0400 From: Alexey Khoroshilov To: Kevin Curtis , "David S . Miller" Cc: Alexey Khoroshilov , netdev@vger.kernel.org, linux-kernel@vger.kernel.org, ldv-project@linuxtesting.org Subject: [PATCH] farsync: fix invalid memory accesses in fst_add_one() and fst_init_card() Date: Sat, 5 Jul 2014 03:35:50 +0400 Message-Id: <1404516950-17900-1-git-send-email-khoroshilov@ispras.ru> X-Mailer: git-send-email 1.9.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org There are several issues in fst_add_one() and fst_init_card(): - invalid pointer dereference at card->ports[card->nports - 1] if register_hdlc_device() fails for the first port in fst_init_card(); - fst_card_array overflow at fst_card_array[no_of_cards_added] because there is no checks for array overflow; - use after free because pointer to deallocated card is left in fst_card_array if something fails after fst_card_array[no_of_cards_added] = card; - several leaks on failure paths in fst_add_one(). The patch fixes all the issues and makes code more readable. Found by Linux Driver Verification project (linuxtesting.org). Signed-off-by: Alexey Khoroshilov --- drivers/net/wan/farsync.c | 106 +++++++++++++++++++++++++--------------------- 1 file changed, 57 insertions(+), 49 deletions(-) diff --git a/drivers/net/wan/farsync.c b/drivers/net/wan/farsync.c index 93ace042d0aa..ff6b659f955d 100644 --- a/drivers/net/wan/farsync.c +++ b/drivers/net/wan/farsync.c @@ -2363,7 +2363,7 @@ static char *type_strings[] = { "FarSync TE1" }; -static void +static int fst_init_card(struct fst_card_info *card) { int i; @@ -2374,24 +2374,25 @@ fst_init_card(struct fst_card_info *card) * we'll have to revise it in some way then. */ for (i = 0; i < card->nports; i++) { - err = register_hdlc_device(card->ports[i].dev); - if (err < 0) { + err = register_hdlc_device(card->ports[i].dev); + if (err < 0) { int j; pr_err("Cannot register HDLC device for port %d (errno %d)\n", - i, -err); + i, -err); for (j = i; j < card->nports; j++) { free_netdev(card->ports[j].dev); card->ports[j].dev = NULL; } - card->nports = i; - break; - } + card->nports = i; + return (card->nports == 0) ? err : 0; + } } pr_info("%s-%s: %s IRQ%d, %d ports\n", port_to_dev(&card->ports[0])->name, port_to_dev(&card->ports[card->nports - 1])->name, type_strings[card->type], card->irq, card->nports); + return 0; } static const struct net_device_ops fst_ops = { @@ -2447,15 +2448,12 @@ fst_add_one(struct pci_dev *pdev, const struct pci_device_id *ent) /* Try to enable the device */ if ((err = pci_enable_device(pdev)) != 0) { pr_err("Failed to enable card. Err %d\n", -err); - kfree(card); - return err; + goto enable_fail; } if ((err = pci_request_regions(pdev, "FarSync")) !=0) { pr_err("Failed to allocate regions. Err %d\n", -err); - pci_disable_device(pdev); - kfree(card); - return err; + goto regions_fail; } /* Get virtual addresses of memory regions */ @@ -2464,30 +2462,21 @@ fst_add_one(struct pci_dev *pdev, const struct pci_device_id *ent) card->phys_ctlmem = pci_resource_start(pdev, 3); if ((card->mem = ioremap(card->phys_mem, FST_MEMSIZE)) == NULL) { pr_err("Physical memory remap failed\n"); - pci_release_regions(pdev); - pci_disable_device(pdev); - kfree(card); - return -ENODEV; + err = -ENODEV; + goto ioremap_physmem_fail; } if ((card->ctlmem = ioremap(card->phys_ctlmem, 0x10)) == NULL) { pr_err("Control memory remap failed\n"); - pci_release_regions(pdev); - pci_disable_device(pdev); - iounmap(card->mem); - kfree(card); - return -ENODEV; + err = -ENODEV; + goto ioremap_ctlmem_fail; } dbg(DBG_PCI, "kernel mem %p, ctlmem %p\n", card->mem, card->ctlmem); /* Register the interrupt handler */ if (request_irq(pdev->irq, fst_intr, IRQF_SHARED, FST_DEV_NAME, card)) { pr_err("Unable to register interrupt %d\n", card->irq); - pci_release_regions(pdev); - pci_disable_device(pdev); - iounmap(card->ctlmem); - iounmap(card->mem); - kfree(card); - return -ENODEV; + err = -ENODEV; + goto irq_fail; } /* Record info we need */ @@ -2513,13 +2502,8 @@ fst_add_one(struct pci_dev *pdev, const struct pci_device_id *ent) while (i--) free_netdev(card->ports[i].dev); pr_err("FarSync: out of memory\n"); - free_irq(card->irq, card); - pci_release_regions(pdev); - pci_disable_device(pdev); - iounmap(card->ctlmem); - iounmap(card->mem); - kfree(card); - return -ENODEV; + err = -ENOMEM; + goto hdlcdev_fail; } card->ports[i].dev = dev; card->ports[i].card = card; @@ -2565,9 +2549,16 @@ fst_add_one(struct pci_dev *pdev, const struct pci_device_id *ent) pci_set_drvdata(pdev, card); /* Remainder of card setup */ + if (no_of_cards_added >= FST_MAX_CARDS) { + pr_err("FarSync: too many cards\n"); + err = -ENOMEM; + goto card_array_fail; + } fst_card_array[no_of_cards_added] = card; card->card_no = no_of_cards_added++; /* Record instance and bump it */ - fst_init_card(card); + err = fst_init_card(card); + if (err) + goto init_card_fail; if (card->family == FST_FAMILY_TXU) { /* * Allocate a dma buffer for transmit and receives @@ -2577,29 +2568,46 @@ fst_add_one(struct pci_dev *pdev, const struct pci_device_id *ent) &card->rx_dma_handle_card); if (card->rx_dma_handle_host == NULL) { pr_err("Could not allocate rx dma buffer\n"); - fst_disable_intr(card); - pci_release_regions(pdev); - pci_disable_device(pdev); - iounmap(card->ctlmem); - iounmap(card->mem); - kfree(card); - return -ENOMEM; + err = -ENOMEM; + goto rx_dma_fail; } card->tx_dma_handle_host = pci_alloc_consistent(card->device, FST_MAX_MTU, &card->tx_dma_handle_card); if (card->tx_dma_handle_host == NULL) { pr_err("Could not allocate tx dma buffer\n"); - fst_disable_intr(card); - pci_release_regions(pdev); - pci_disable_device(pdev); - iounmap(card->ctlmem); - iounmap(card->mem); - kfree(card); - return -ENOMEM; + err = -ENOMEM; + goto tx_dma_fail; } } return 0; /* Success */ + +tx_dma_fail: + pci_free_consistent(card->device, FST_MAX_MTU, + card->rx_dma_handle_host, + card->rx_dma_handle_card); +rx_dma_fail: + fst_disable_intr(card); + for (i = 0 ; i < card->nports ; i++) + unregister_hdlc_device(card->ports[i].dev); +init_card_fail: + fst_card_array[card->card_no] = NULL; +card_array_fail: + for (i = 0 ; i < card->nports ; i++) + free_netdev(card->ports[i].dev); +hdlcdev_fail: + free_irq(card->irq, card); +irq_fail: + iounmap(card->ctlmem); +ioremap_ctlmem_fail: + iounmap(card->mem); +ioremap_physmem_fail: + pci_release_regions(pdev); +regions_fail: + pci_disable_device(pdev); +enable_fail: + kfree(card); + return err; } /* -- 1.9.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/