diff options
| author | Jakub Kicinski <kuba@kernel.org> | 2026-05-10 22:29:02 +0300 |
|---|---|---|
| committer | Paolo Abeni <pabeni@redhat.com> | 2026-05-12 17:15:00 +0300 |
| commit | 8d5806c600fddb907ebe378f9c366d4b52ac3a39 (patch) | |
| tree | bcd14a27b4bb8a353790be06da07c43a4fcdf7e2 | |
| parent | fbf5df34a4dbcd09d433dd4f0916bf9b2ddb16de (diff) | |
| download | linux-8d5806c600fddb907ebe378f9c366d4b52ac3a39.tar.xz | |
net: shaper: reject handle IDs exceeding internal bit-width
net_shaper_parse_handle() reads the user-supplied handle ID via
nla_get_u32(), accepting the full u32 range. However, the xarray key
is built by net_shaper_handle_to_index() using
FIELD_PREP(NET_SHAPER_ID_MASK, handle->id), where NET_SHAPER_ID_MASK
is GENMASK(25, 0) - only 26 bits wide. FIELD_PREP silently masks off
the upper bits at runtime. A user-supplied NODE id like 0x04000123
becomes id 0x123.
Additionally, a user-supplied id equal to NET_SHAPER_ID_UNSPEC
(0x03FFFFFF, which is NET_SHAPER_ID_MASK itself) would collide with
the sentinel used internally by the group operation to signal
"allocate a new NODE id".
Reject user-supplied IDs >= NET_SHAPER_ID_MASK (i.e., >= 0x03FFFFFF)
in the policy.
Fixes: 4b623f9f0f59 ("net-shapers: implement NL get operation")
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Link: https://patch.msgid.link/20260510192904.3987113-9-kuba@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
| -rw-r--r-- | Documentation/netlink/specs/net_shaper.yaml | 7 | ||||
| -rw-r--r-- | net/shaper/shaper.c | 4 | ||||
| -rw-r--r-- | net/shaper/shaper_nl_gen.c | 7 | ||||
| -rw-r--r-- | net/shaper/shaper_nl_gen.h | 2 |
4 files changed, 18 insertions, 2 deletions
diff --git a/Documentation/netlink/specs/net_shaper.yaml b/Documentation/netlink/specs/net_shaper.yaml index 3f2ad772b64b..de01f922040a 100644 --- a/Documentation/netlink/specs/net_shaper.yaml +++ b/Documentation/netlink/specs/net_shaper.yaml @@ -34,6 +34,11 @@ doc: | definitions: - + type: const + name: max-handle-id + value: 0x3fffffe + scope: kernel + - type: enum name: scope doc: Defines the shaper @id interpretation. @@ -140,6 +145,8 @@ attribute-sets: - name: id type: u32 + checks: + max: max-handle-id doc: | Numeric identifier of a shaper. The id semantic depends on the scope. For @queue scope it's the queue id and for @node diff --git a/net/shaper/shaper.c b/net/shaper/shaper.c index 08fde2d9e8aa..eb049847fed6 100644 --- a/net/shaper/shaper.c +++ b/net/shaper/shaper.c @@ -21,6 +21,8 @@ #define NET_SHAPER_ID_UNSPEC NET_SHAPER_ID_MASK +static_assert(NET_SHAPER_ID_UNSPEC == NET_SHAPER_MAX_HANDLE_ID + 1); + struct net_shaper_hierarchy { struct xarray shapers; }; @@ -360,7 +362,7 @@ static int net_shaper_pre_insert(struct net_shaper_binding *binding, handle->id == NET_SHAPER_ID_UNSPEC) { u32 min, max; - handle->id = NET_SHAPER_ID_MASK - 1; + handle->id = NET_SHAPER_MAX_HANDLE_ID; max = net_shaper_handle_to_index(handle); handle->id = 0; min = net_shaper_handle_to_index(handle); diff --git a/net/shaper/shaper_nl_gen.c b/net/shaper/shaper_nl_gen.c index 9b29be3ef19a..76eff85ec66d 100644 --- a/net/shaper/shaper_nl_gen.c +++ b/net/shaper/shaper_nl_gen.c @@ -11,10 +11,15 @@ #include <uapi/linux/net_shaper.h> +/* Integer value ranges */ +static const struct netlink_range_validation net_shaper_a_handle_id_range = { + .max = NET_SHAPER_MAX_HANDLE_ID, +}; + /* Common nested types */ const struct nla_policy net_shaper_handle_nl_policy[NET_SHAPER_A_HANDLE_ID + 1] = { [NET_SHAPER_A_HANDLE_SCOPE] = NLA_POLICY_MAX(NLA_U32, 3), - [NET_SHAPER_A_HANDLE_ID] = { .type = NLA_U32, }, + [NET_SHAPER_A_HANDLE_ID] = NLA_POLICY_FULL_RANGE(NLA_U32, &net_shaper_a_handle_id_range), }; const struct nla_policy net_shaper_leaf_info_nl_policy[NET_SHAPER_A_WEIGHT + 1] = { diff --git a/net/shaper/shaper_nl_gen.h b/net/shaper/shaper_nl_gen.h index 42c46c52c775..2406652a9014 100644 --- a/net/shaper/shaper_nl_gen.h +++ b/net/shaper/shaper_nl_gen.h @@ -12,6 +12,8 @@ #include <uapi/linux/net_shaper.h> +#define NET_SHAPER_MAX_HANDLE_ID 67108862 + /* Common nested types */ extern const struct nla_policy net_shaper_handle_nl_policy[NET_SHAPER_A_HANDLE_ID + 1]; extern const struct nla_policy net_shaper_leaf_info_nl_policy[NET_SHAPER_A_WEIGHT + 1]; |