4.9-stable review patch. If anyone has any objections, please let me know.
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From: Breno Leitao leitao@debian.org
[ Upstream commit 1262dc09dc9ae7bf4ad00b6a2c5ed6a6936bcd10 ]
Currently an open firmware property is copied into partition_name variable without keeping a room for \0.
Later one, this variable (partition_name), which is 97 bytes long, is strncpyed into ibmvcsci_host_data->madapter_info->partition_name, which is 96 bytes long, possibly truncating it 'again' and removing the \0.
This patch simply decreases the partition name to 96 and just copy using strlcpy() which guarantees that the string is \0 terminated. I think there is no issue if this there is a truncation in this very first copy, i.e, when the open firmware property is read and copied into the driver for the very first time;
This issue also causes the following warning on GCC 8:
drivers/scsi/ibmvscsi/ibmvscsi.c:281:2: warning: strncpy output may be truncated copying 96 bytes from a string of length 96 [-Wstringop-truncation] ... inlined from ibmvscsi_probe at drivers/scsi/ibmvscsi/ibmvscsi.c:2221:7: drivers/scsi/ibmvscsi/ibmvscsi.c:265:3: warning: strncpy specified bound 97 equals destination size [-Wstringop-truncation]
CC: Bart Van Assche bart.vanassche@wdc.com CC: Tyrel Datwyler tyreld@linux.vnet.ibm.com Signed-off-by: Breno Leitao leitao@debian.org Acked-by: Tyrel Datwyler tyreld@linux.vnet.ibm.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/scsi/ibmvscsi/ibmvscsi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c +++ b/drivers/scsi/ibmvscsi/ibmvscsi.c @@ -93,7 +93,7 @@ static int max_requests = IBMVSCSI_MAX_R static int max_events = IBMVSCSI_MAX_REQUESTS_DEFAULT + 2; static int fast_fail = 1; static int client_reserve = 1; -static char partition_name[97] = "UNKNOWN"; +static char partition_name[96] = "UNKNOWN"; static unsigned int partition_number = -1;
static struct scsi_transport_template *ibmvscsi_transport_template; @@ -259,7 +259,7 @@ static void gather_partition_info(void)
ppartition_name = of_get_property(of_root, "ibm,partition-name", NULL); if (ppartition_name) - strncpy(partition_name, ppartition_name, + strlcpy(partition_name, ppartition_name, sizeof(partition_name)); p_number_ptr = of_get_property(of_root, "ibm,partition-no", NULL); if (p_number_ptr)