From 46de06839b4936cc5fd4e6638b8fbf8437bce29e Mon Sep 17 00:00:00 2001 From: Daniel Kim Date: Wed, 30 Jul 2014 13:20:00 +0200 Subject: [PATCH] brcmfmac: Do not use strcpy and strcat Commit "c1b2053 brcmfmac: Make firmware path a module parameter" introduced use of strcpy and strcat. The strcpy and strcat require using null terminated strings and can cause out-of-bounds memory access and subsequent corruption. This patch replaces these by strncpy and strncat respectively to assure array boundaries are not crossed. Reviewed-by: Pieter-Paul Giesberts Reviewed-by: Arend Van Spriel Signed-off-by: Daniel Kim Signed-off-by: Arend van Spriel Signed-off-by: John W. Linville --- .../wireless/brcm80211/brcmfmac/dhd_sdio.c | 25 +++++++++++++------ 1 file changed, 18 insertions(+), 7 deletions(-) diff --git a/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c b/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c index 67d91d5cc13d..f55f625fd06b 100644 --- a/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c +++ b/drivers/net/wireless/brcm80211/brcmfmac/dhd_sdio.c @@ -670,6 +670,8 @@ static int brcmf_sdio_get_fwnames(struct brcmf_chip *ci, struct brcmf_sdio_dev *sdiodev) { int i; + uint fw_len, nv_len; + char end; for (i = 0; i < ARRAY_SIZE(brcmf_fwname_data); i++) { if (brcmf_fwname_data[i].chipid == ci->chip && @@ -682,16 +684,25 @@ static int brcmf_sdio_get_fwnames(struct brcmf_chip *ci, return -ENODEV; } + fw_len = sizeof(sdiodev->fw_name) - 1; + nv_len = sizeof(sdiodev->nvram_name) - 1; /* check if firmware path is provided by module parameter */ if (brcmf_firmware_path[0] != '\0') { - if (brcmf_firmware_path[strlen(brcmf_firmware_path) - 1] != '/') - strcat(brcmf_firmware_path, "/"); - - strcpy(sdiodev->fw_name, brcmf_firmware_path); - strcpy(sdiodev->nvram_name, brcmf_firmware_path); + strncpy(sdiodev->fw_name, brcmf_firmware_path, fw_len); + strncpy(sdiodev->nvram_name, brcmf_firmware_path, nv_len); + fw_len -= strlen(sdiodev->fw_name); + nv_len -= strlen(sdiodev->nvram_name); + + end = brcmf_firmware_path[strlen(brcmf_firmware_path) - 1]; + if (end != '/') { + strncat(sdiodev->fw_name, "/", fw_len); + strncat(sdiodev->nvram_name, "/", nv_len); + fw_len--; + nv_len--; + } } - strcat(sdiodev->fw_name, brcmf_fwname_data[i].bin); - strcat(sdiodev->nvram_name, brcmf_fwname_data[i].nv); + strncat(sdiodev->fw_name, brcmf_fwname_data[i].bin, fw_len); + strncat(sdiodev->nvram_name, brcmf_fwname_data[i].nv, nv_len); return 0; } -- 2.39.2