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| author | Lin Ma <linma@zju.edu.cn> | 2023-07-25 10:33:30 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2023-08-11 12:08:12 +0200 |
| commit | 24772cc31f0074fb8dbb9f3f2733784dc8bd6673 (patch) | |
| tree | 33996c15e207ff7ba1196182e740bc706b156e21 /net | |
| parent | d628ba98eb1637acce44001e04c718d8dbb1f7ce (diff) | |
| download | linux-24772cc31f0074fb8dbb9f3f2733784dc8bd6673.tar.gz | |
bpf: Add length check for SK_DIAG_BPF_STORAGE_REQ_MAP_FD parsing
[ Upstream commit bcc29b7f5af6797702c2306a7aacb831fc5ce9cb ]
The nla_for_each_nested parsing in function bpf_sk_storage_diag_alloc
does not check the length of the nested attribute. This can lead to an
out-of-attribute read and allow a malformed nlattr (e.g., length 0) to
be viewed as a 4 byte integer.
This patch adds an additional check when the nlattr is getting counted.
This makes sure the latter nla_get_u32 can access the attributes with
the correct length.
Fixes: 1ed4d92458a9 ("bpf: INET_DIAG support in bpf_sk_storage")
Suggested-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Lin Ma <linma@zju.edu.cn>
Reviewed-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/r/20230725023330.422856-1-linma@zju.edu.cn
Signed-off-by: Martin KaFai Lau <martin.lau@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'net')
| -rw-r--r-- | net/core/bpf_sk_storage.c | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/net/core/bpf_sk_storage.c b/net/core/bpf_sk_storage.c index 94374d529ea4..ad01b1bea52e 100644 --- a/net/core/bpf_sk_storage.c +++ b/net/core/bpf_sk_storage.c @@ -531,8 +531,11 @@ bpf_sk_storage_diag_alloc(const struct nlattr *nla_stgs) return ERR_PTR(-EPERM); nla_for_each_nested(nla, nla_stgs, rem) { - if (nla_type(nla) == SK_DIAG_BPF_STORAGE_REQ_MAP_FD) + if (nla_type(nla) == SK_DIAG_BPF_STORAGE_REQ_MAP_FD) { + if (nla_len(nla) != sizeof(u32)) + return ERR_PTR(-EINVAL); nr_maps++; + } } diag = kzalloc(struct_size(diag, maps, nr_maps), GFP_KERNEL); |