From 253683bbfb6bc5864417c8c35cb6ef13b5e259e6 Mon Sep 17 00:00:00 2001 From: David Howells Date: Fri, 21 May 2010 02:25:27 +0000 Subject: rtnetlink: Fix error handling in do_setlink() Commit c02db8c6290bb992442fec1407643c94cc414375: Author: Chris Wright Date: Sun May 16 01:05:45 2010 -0700 Subject: rtnetlink: make SR-IOV VF interface symmetric adds broken error handling to do_setlink() in net/core/rtnetlink.c. The problem is the following chunk of code: if (tb[IFLA_VFINFO_LIST]) { struct nlattr *attr; int rem; nla_for_each_nested(attr, tb[IFLA_VFINFO_LIST], rem) { if (nla_type(attr) != IFLA_VF_INFO) ----> goto errout; err = do_setvfinfo(dev, attr); if (err < 0) goto errout; modified = 1; } } which can get to errout without setting err, resulting in the following error: net/core/rtnetlink.c: In function 'do_setlink': net/core/rtnetlink.c:904: warning: 'err' may be used uninitialized in this function Change the code to return -EINVAL in this case. Note that this might not be the appropriate error though. Signed-off-by: David Howells cc: Chris Wright cc: David S. Miller Acked-by: Chris Wright Signed-off-by: David S. Miller --- net/core/rtnetlink.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'net/core/rtnetlink.c') diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index e4b9870e4706..7ab86f3a1ea4 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -1199,8 +1199,10 @@ static int do_setlink(struct net_device *dev, struct ifinfomsg *ifm, struct nlattr *attr; int rem; nla_for_each_nested(attr, tb[IFLA_VFINFO_LIST], rem) { - if (nla_type(attr) != IFLA_VF_INFO) + if (nla_type(attr) != IFLA_VF_INFO) { + err = -EINVAL; goto errout; + } err = do_setvfinfo(dev, attr); if (err < 0) goto errout; -- cgit v1.2.1 From 8ca9418350eccd5dd2659931807c1901224dd638 Mon Sep 17 00:00:00 2001 From: Scott Feldman Date: Fri, 28 May 2010 03:42:18 -0700 Subject: netlink: bug fix: don't overrun skbs on vf_port dump Noticed by Patrick McHardy: was continuing to fill skb after a nla_put_failure, ignoring the size calculated by upper layer. Now, return -EMSGSIZE on any overruns, but also allow netdev to fail ndo_get_vf_port with error other than -EMSGSIZE, thus unwinding nest. Signed-off-by: Scott Feldman Signed-off-by: David S. Miller --- net/core/rtnetlink.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) (limited to 'net/core/rtnetlink.c') diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 7ab86f3a1ea4..7331bb2f6b9c 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -722,14 +722,13 @@ static int rtnl_vf_ports_fill(struct sk_buff *skb, struct net_device *dev) for (vf = 0; vf < dev_num_vf(dev->dev.parent); vf++) { vf_port = nla_nest_start(skb, IFLA_VF_PORT); - if (!vf_port) { - nla_nest_cancel(skb, vf_ports); - return -EMSGSIZE; - } + if (!vf_port) + goto nla_put_failure; NLA_PUT_U32(skb, IFLA_PORT_VF, vf); err = dev->netdev_ops->ndo_get_vf_port(dev, vf, skb); + if (err == -EMSGSIZE) + goto nla_put_failure; if (err) { -nla_put_failure: nla_nest_cancel(skb, vf_port); continue; } @@ -739,6 +738,10 @@ nla_put_failure: nla_nest_end(skb, vf_ports); return 0; + +nla_put_failure: + nla_nest_cancel(skb, vf_ports); + return -EMSGSIZE; } static int rtnl_port_self_fill(struct sk_buff *skb, struct net_device *dev) @@ -753,7 +756,7 @@ static int rtnl_port_self_fill(struct sk_buff *skb, struct net_device *dev) err = dev->netdev_ops->ndo_get_vf_port(dev, PORT_SELF_VF, skb); if (err) { nla_nest_cancel(skb, port_self); - return err; + return (err == -EMSGSIZE) ? err : 0; } nla_nest_end(skb, port_self); -- cgit v1.2.1 From 045de01a174d9f0734f657eb4b3313d89b4fd5ad Mon Sep 17 00:00:00 2001 From: Scott Feldman Date: Fri, 28 May 2010 03:42:43 -0700 Subject: netlink: bug fix: wrong size was calculated for vfinfo list blob The wrong size was being calculated for vfinfo. In one case, it was over- calculating using nlmsg_total_size on attrs, in another case, it was under-calculating by assuming ifla_vf_* structs are packed together, but each struct is it's own attr w/ hdr (and padding). Signed-off-by: Scott Feldman Signed-off-by: David S. Miller --- net/core/rtnetlink.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'net/core/rtnetlink.c') diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 7331bb2f6b9c..1a2af24e9e3d 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -650,11 +650,12 @@ static inline int rtnl_vfinfo_size(const struct net_device *dev) if (dev->dev.parent && dev_is_pci(dev->dev.parent)) { int num_vfs = dev_num_vf(dev->dev.parent); - size_t size = nlmsg_total_size(sizeof(struct nlattr)); - size += nlmsg_total_size(num_vfs * sizeof(struct nlattr)); - size += num_vfs * (sizeof(struct ifla_vf_mac) + - sizeof(struct ifla_vf_vlan) + - sizeof(struct ifla_vf_tx_rate)); + size_t size = nla_total_size(sizeof(struct nlattr)); + size += nla_total_size(num_vfs * sizeof(struct nlattr)); + size += num_vfs * + (nla_total_size(sizeof(struct ifla_vf_mac)) + + nla_total_size(sizeof(struct ifla_vf_vlan)) + + nla_total_size(sizeof(struct ifla_vf_tx_rate))); return size; } else return 0; -- cgit v1.2.1