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| author | Lin Ma <linma@zju.edu.cn> | 2023-08-01 04:32:48 +0300 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2023-08-02 07:07:46 +0300 |
| commit | 31d49ba033095f6e8158c60f69714a500922e0c3 (patch) | |
| tree | 1e53a077d010b321ddd399be4a2edf3eba9c48f3 /net/dcb | |
| parent | 4a4474e3bf8af318e556c6c9bfa9ce24103d5c8d (diff) | |
| download | linux-31d49ba033095f6e8158c60f69714a500922e0c3.tar.xz | |
net: dcb: choose correct policy to parse DCB_ATTR_BCN
The dcbnl_bcn_setcfg uses erroneous policy to parse tb[DCB_ATTR_BCN],
which is introduced in commit 859ee3c43812 ("DCB: Add support for DCB
BCN"). Please see the comment in below code
static int dcbnl_bcn_setcfg(...)
{
...
ret = nla_parse_nested_deprecated(..., dcbnl_pfc_up_nest, .. )
// !!! dcbnl_pfc_up_nest for attributes
// DCB_PFC_UP_ATTR_0 to DCB_PFC_UP_ATTR_ALL in enum dcbnl_pfc_up_attrs
...
for (i = DCB_BCN_ATTR_RP_0; i <= DCB_BCN_ATTR_RP_7; i++) {
// !!! DCB_BCN_ATTR_RP_0 to DCB_BCN_ATTR_RP_7 in enum dcbnl_bcn_attrs
...
value_byte = nla_get_u8(data[i]);
...
}
...
for (i = DCB_BCN_ATTR_BCNA_0; i <= DCB_BCN_ATTR_RI; i++) {
// !!! DCB_BCN_ATTR_BCNA_0 to DCB_BCN_ATTR_RI in enum dcbnl_bcn_attrs
...
value_int = nla_get_u32(data[i]);
...
}
...
}
That is, the nla_parse_nested_deprecated uses dcbnl_pfc_up_nest
attributes to parse nlattr defined in dcbnl_pfc_up_attrs. But the
following access code fetch each nlattr as dcbnl_bcn_attrs attributes.
By looking up the associated nla_policy for dcbnl_bcn_attrs. We can find
the beginning part of these two policies are "same".
static const struct nla_policy dcbnl_pfc_up_nest[...] = {
[DCB_PFC_UP_ATTR_0] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_1] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_2] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_3] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_4] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_5] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_6] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_7] = {.type = NLA_U8},
[DCB_PFC_UP_ATTR_ALL] = {.type = NLA_FLAG},
};
static const struct nla_policy dcbnl_bcn_nest[...] = {
[DCB_BCN_ATTR_RP_0] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_1] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_2] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_3] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_4] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_5] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_6] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_7] = {.type = NLA_U8},
[DCB_BCN_ATTR_RP_ALL] = {.type = NLA_FLAG},
// from here is somewhat different
[DCB_BCN_ATTR_BCNA_0] = {.type = NLA_U32},
...
[DCB_BCN_ATTR_ALL] = {.type = NLA_FLAG},
};
Therefore, the current code is buggy and this
nla_parse_nested_deprecated could overflow the dcbnl_pfc_up_nest and use
the adjacent nla_policy to parse attributes from DCB_BCN_ATTR_BCNA_0.
Hence use the correct policy dcbnl_bcn_nest to parse the nested
tb[DCB_ATTR_BCN] TLV.
Fixes: 859ee3c43812 ("DCB: Add support for DCB BCN")
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://lore.kernel.org/r/20230801013248.87240-1-linma@zju.edu.cn
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/dcb')
| -rw-r--r-- | net/dcb/dcbnl.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/net/dcb/dcbnl.c b/net/dcb/dcbnl.c index c0c438128575..2e6b8c8fd2de 100644 --- a/net/dcb/dcbnl.c +++ b/net/dcb/dcbnl.c @@ -980,7 +980,7 @@ static int dcbnl_bcn_setcfg(struct net_device *netdev, struct nlmsghdr *nlh, return -EOPNOTSUPP; ret = nla_parse_nested_deprecated(data, DCB_BCN_ATTR_MAX, - tb[DCB_ATTR_BCN], dcbnl_pfc_up_nest, + tb[DCB_ATTR_BCN], dcbnl_bcn_nest, NULL); if (ret) return ret; |