bpf: hashtab: fix 32-bit overflow in memory usage calculation #6311
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The intermediate product value_size * num_possible_cpus() is evaluated in 32-bit arithmetic and only then promoted to 64 bits. On systems with large value_size and many possible CPUs this can overflow and lead to an underestimated memory usage. Cast value_size to u64 before multiplying. Found by Linux Verification Center (linuxtesting.org) with SVACE. Fixes: 304849a ("bpf: hashtab memory usage") Cc: [email protected] Signed-off-by: Alexei Safin <[email protected]>
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Upstream branch: b54a8e1 |
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At least one diff in series https://patchwork.kernel.org/project/netdevbpf/list/?series=1020643 irrelevant now. Closing PR. |
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Pull request for series with
subject: bpf: hashtab: fix 32-bit overflow in memory usage calculation
version: 1
url: https://patchwork.kernel.org/project/netdevbpf/list/?series=1020643