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SubjectRe: [PATCH] af_unix: Add sockaddr length checks before accessing sa_family in bind and connect handlers
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From: Mateusz Jurczyk <mjurczyk@google.com>
Date: Thu, 8 Jun 2017 11:13:36 +0200

> Verify that the caller-provided sockaddr structure is large enough to
> contain the sa_family field, before accessing it in bind() and connect()
> handlers of the AF_UNIX socket. Since neither syscall enforces a minimum
> size of the corresponding memory region, very short sockaddrs (zero or
> one byte long) result in operating on uninitialized memory while
> referencing .sa_family.
>
> Signed-off-by: Mateusz Jurczyk <mjurczyk@google.com>

The sockaddr comes from a structure on the caller's kernel stack, even
if the user gives a smaller length, it is legal to access that memory.

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