[PATCH] ibmvnic: Define vnic_login_client_data name field as unsized array
From: Kees Cook <hidden>
Date: 2018-04-10 22:26:50
Also in:
lkml, netdev
Subsystem:
ibm power sriov virtual nic device driver, linux for powerpc (32-bit and 64-bit), networking drivers, the rest · Maintainers:
Haren Myneni, Rick Lindsley, Madhavan Srinivasan, Andrew Lunn, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
The "name" field of struct vnic_login_client_data is a char array of undefined length. This should be written as "char name[]" so the compiler can make better decisions about the field (for example, not assuming it's a single character). This was noticed while trying to tighten the CONFIG_FORTIFY_SOURCE checking. Signed-off-by: Kees Cook <redacted> --- drivers/net/ethernet/ibm/ibmvnic.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/drivers/net/ethernet/ibm/ibmvnic.c b/drivers/net/ethernet/ibm/ibmvnic.c
index aad5658d79d5..35fbb41cd2d4 100644
--- a/drivers/net/ethernet/ibm/ibmvnic.c
+++ b/drivers/net/ethernet/ibm/ibmvnic.c@@ -3170,7 +3170,7 @@ static int send_version_xchg(struct ibmvnic_adapter *adapter) struct vnic_login_client_data { u8 type; __be16 len; - char name; + char name[]; } __packed; static int vnic_client_data_len(struct ibmvnic_adapter *adapter)
@@ -3199,21 +3199,21 @@ static void vnic_add_client_data(struct ibmvnic_adapter *adapter, vlcd->type = 1; len = strlen(os_name) + 1; vlcd->len = cpu_to_be16(len); - strncpy(&vlcd->name, os_name, len); - vlcd = (struct vnic_login_client_data *)((char *)&vlcd->name + len); + strncpy(vlcd->name, os_name, len); + vlcd = (struct vnic_login_client_data *)(vlcd->name + len); /* Type 2 - LPAR name */ vlcd->type = 2; len = strlen(utsname()->nodename) + 1; vlcd->len = cpu_to_be16(len); - strncpy(&vlcd->name, utsname()->nodename, len); - vlcd = (struct vnic_login_client_data *)((char *)&vlcd->name + len); + strncpy(vlcd->name, utsname()->nodename, len); + vlcd = (struct vnic_login_client_data *)(vlcd->name + len); /* Type 3 - device name */ vlcd->type = 3; len = strlen(adapter->netdev->name) + 1; vlcd->len = cpu_to_be16(len); - strncpy(&vlcd->name, adapter->netdev->name, len); + strncpy(vlcd->name, adapter->netdev->name, len); } static int send_login(struct ibmvnic_adapter *adapter)
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2.7.4
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Kees Cook
Pixel Security