Messages in this thread | | | From | Richard Weinberger <> | Subject | Re: [PATCH] bpf: devmap: Check attr->max_entries more carefully | Date | Mon, 16 Oct 2017 00:13:43 +0200 |
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Am Montag, 16. Oktober 2017, 00:00:20 CEST schrieb Richard Weinberger: > max_entries is user controlled and used as input for __alloc_percpu(). > This function expects that the allocation size is a power of two and > less than PCPU_MIN_UNIT_SIZE. > Otherwise a WARN() is triggered.
On a second though, I think we should also have a hard limit for ->max_entries or check for an overflow here:
static u64 dev_map_bitmap_size(const union bpf_attr *attr) { return BITS_TO_LONGS(attr->max_entries) * sizeof(unsigned long); }
Thanks, //richard
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