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Message-ID: <1494624236.4521.4.camel@gmail.com>
Subject: Re: [kernel-hardening] Re: [PATCH v9 1/4] syscalls: Verify address
 limit before returning to user-mode
From: Daniel Micay <danielmicay@gmail.com>
To: Kees Cook <keescook@chromium.org>, Al Viro <viro@zeniv.linux.org.uk>
Cc: Russell King - ARM Linux <linux@armlinux.org.uk>,
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> overflow into adjacent allocations (fixed by VMAP_STACK).

99% fixed, but it's possible to skip over the guard page without
-fstack-check enabled (plus some edge cases need to be fixed in GCC),
unless VLAs were forbidden in addition to the existing large frame size
warning.

I'm not sure about in-tree code, but Qualcomm had some of these
improperly bounded VLA vulnerabilities in their MSM kernel...