Date: Mon, 22 Nov 2021 12:25:44 -0500 From: Shawn Webb <shawn.webb@hardenedbsd.org> To: Mark Johnston <markj@FreeBSD.org> Cc: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org Subject: Re: git: 68396709e73a - releng/12.3 - libctf: Improve check for duplicate SOU definitions in ctf_add_type() Message-ID: <20211122172544.a3wi636tajsnsfme@mutt-hbsd> In-Reply-To: <202111221634.1AMGYoK4064366@gitrepo.freebsd.org> References: <202111221634.1AMGYoK4064366@gitrepo.freebsd.org>
next in thread | previous in thread | raw e-mail | index | archive | help
--6n2yojvmhxmacvco Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Mon, Nov 22, 2021 at 04:34:50PM +0000, Mark Johnston wrote: > The branch releng/12.3 has been updated by markj: >=20 > URL: https://cgit.FreeBSD.org/src/commit/?id=3D68396709e73a4cd392ffc06fde= 6bfa44d79118a7 >=20 > commit 68396709e73a4cd392ffc06fde6bfa44d79118a7 > Author: Mark Johnston <markj@FreeBSD.org> > AuthorDate: 2021-10-04 16:28:22 +0000 > Commit: Mark Johnston <markj@FreeBSD.org> > CommitDate: 2021-11-22 16:32:18 +0000 >=20 > libctf: Improve check for duplicate SOU definitions in ctf_add_type() > =20 > When copying a struct or union from one CTF container to another, > ctf_add_type() checks whether it matches an existing type in the > destination container. It does so by looking for a type with the same > name and kind as the new type, and if one exists, it iterates over all > members of the source type and checks whether a member with matching > name and offset exists in the matched destination type. This can > produce false positives, for example because member types are not > compared, but this is not expected to arise in practice. If the match > fails, ctf_add_type() returns an error. > =20 > The procedure used for member comparison breaks down in the face of > anonymous struct and union members. ctf_member_iter() visits each > member in the source definition and looks up the corresponding member= in > the desination definition by name using ctf_member_info(), but this > function will descend into anonymous members and thus fail to match. > Fix the problem by introducing a custom comparison routine which does > not assume member names are unique. This should also be faster for > types with many members; in the previous scheme, membcmp() would perf= orm > a linear scan of the desination type's members to perform a lookup by > name. The new routine steps through the members of both types in a > single loop. Hey Mark, Out of curiosity, would commits to releng branches necessitate an EN? Thanks, --=20 Shawn Webb Cofounder / Security Engineer HardenedBSD https://git.hardenedbsd.org/hardenedbsd/pubkeys/-/raw/master/Shawn_Webb/03A= 4CBEBB82EA5A67D9F3853FF2E67A277F8E1FA.pub.asc --6n2yojvmhxmacvco Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEA6TL67gupaZ9nzhT/y5nonf44foFAmGb0pUACgkQ/y5nonf4 4foDzQ//X8YXxXyUOJW4tZd8G/YkAjFYeGrEKZebnhb5HWBjZMlaM62jZ4HngxQA hw7C5biyZk9AWsghnvbuccLOzFn7IXV2CHJTDFWeNKLxfZ9xdwigBOVf9omAw0kE A6Zif1OT3QysH4YmrK5I3JuOhc02MIVP4lwjCH040c/k+fwgA5WToMO8MpDULuRk k9U2UbATWkZKpvKLrWD9m36/BkmmpfwjLot+3RpQXeDy9lwLrgEiA8gOO21holAt igyxJj/aqW3qB4wOsKIazCbW+aV654EUrQB1Sr7nzXyigEwg9+z8QSztAM86s7RG bZYBkQb8EZqDyKajHF+kuBcGZI8QhFs4S5AZrMHew1UuB2wD39fwHHhcOTpcdttT eGF2jrr3hpr3L3L0zFZgRuCHuucONm5pGClmTpTi69woFe4dQn4431bPpGkVj6vb BOMO5YynK729WPX0qA5jkq0gI+Yt/4pm8Oej+NUNbmq6XjTUTXXNhppNS+LXfHwd Ws6s49xVlqv4bwv7/SUaJPcdJ1HHbco6ZFB7Yd4lJ/RhirOw+NmkF3bUflKK2lyg r5xMfnK7Y+EJcSvFBJVEVD3utEVZ+lFc3Qbp1Fjh/ko6IJezHNI4FimJJMBiiKq8 rDf8kJ6paZoIdZ4MlZgGu4JSIi832L0JSCj03worELN4NM0sBjY= =64oi -----END PGP SIGNATURE----- --6n2yojvmhxmacvco--
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20211122172544.a3wi636tajsnsfme>