devmap: Use bpf_map_area_alloc() for allocating hash buckets

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Syzkaller discovered that creating a hash of type devmap_hash with a large
number of entries can hit the memory allocator limit for allocating
contiguous memory regions. There's really no reason to use kmalloc_array()
directly in the devmap code, so just switch it to the existing
bpf_map_area_alloc() function that is used elsewhere.

Fixes: 6f9d451ab1 ("xdp: Add devmap_hash map type for looking up devices by hashed index")
Reported-by: Xiumei Mu <xmu@redhat.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200616142829.114173-1-toke@redhat.com

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Toke Høiland-Jørgensen 2020-06-16 16:28:29 +02:00 • committed by Alexei Starovoitov

parent 3ff2351651

commit 99c51064fb

1 changed files with 6 additions and 4 deletions

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kernel/bpf/devmap.c

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