From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:54247) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZtvvO-0002Sy-PN for qemu-devel@nongnu.org; Wed, 04 Nov 2015 06:08:34 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZtvvG-0005qS-8k for qemu-devel@nongnu.org; Wed, 04 Nov 2015 06:08:18 -0500 Date: Wed, 4 Nov 2015 12:08:02 +0100 From: Kevin Wolf Message-ID: <20151104110802.GB4026@noname.redhat.com> References: <1446507126-28603-1-git-send-email-jsnow@redhat.com> <5637F5F2.4050202@redhat.com> MIME-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="u3/rZRmxL6MmkK24" Content-Disposition: inline In-Reply-To: <5637F5F2.4050202@redhat.com> Subject: Re: [Qemu-devel] [PATCH] qcow2: avoid misaligned 64bit bswap List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Eric Blake Cc: John Snow , qemu-devel@nongnu.org, qemu-block@nongnu.org, mreitz@redhat.com --u3/rZRmxL6MmkK24 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable Am 03.11.2015 um 00:46 hat Eric Blake geschrieben: > On 11/02/2015 04:32 PM, John Snow wrote: > > If we create a buffer directly on the stack by using 12 bytes, there's > > no guarantee the 64bit value we want to swap will be aligned, which > > could cause errors with undefined behavior. > >=20 > > Spotted with clang -fsanitize=3Dundefined and observed in iotests 15, 2= 6, > > 44, 115 and 121. > >=20 > > Signed-off-by: John Snow > > --- > > block/qcow2-refcount.c | 11 +++++++---- > > 1 file changed, 7 insertions(+), 4 deletions(-) >=20 > Reviewed-by: Eric Blake Thanks, applied to the block branch. Kevin --u3/rZRmxL6MmkK24 Content-Type: application/pgp-signature -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iQIcBAEBAgAGBQJWOecSAAoJEH8JsnLIjy/WnlIP/RteWWu1W2CZkVVle0FcRz85 wlvHT2vy/Th5CGPC/VegNxMtGI9KVYD/2gGgpfvU0LoQHsQEFBo8uSXuFTEMLQKq 9p9oAMSC20AvsYMS6bIGpPtiRcT2ARGyW9XwEqs7lSmvb0L6SdEVrHEsQT/6jxOv +KbbBopEiZXiGd7FCq9eUfjasp4Xt2eJ+NNMWadmMdOu60YaN+5lp2v2MzVmPnql FarQbi9fS8rV3vqPHxbYOmeW0Ma6ZhrBP436pprTDhghYFo6wJs2ZodpBBDZkJvy YkZEUHWE+ZBCv9GN1uHRYN4OCTLg2W8/ONlnN5w00CpNKsfxq+2c3GVlmVmy8ypE 2Q+kE+bloiXdr9QUjrLEN1DWyKNDBLorlBZvKD95+F870OY8idu3suOqlXZHk5/T 1fkpdOVKgdR7m2t9LSKv5nPYDgxLOcPPm3xp3BkbSn+B/lpISzLwzmWm1FK1gcQ4 /VTSKLOombbYAGlNDNsEx7dZL2bZJom2pw2581TcnUC+5OxAX8t0xNZ+QDmU7KHG oCkLawHEcZXDcyxbjU2pZNtuBeD2hIcsZggdiLRaMbm2KXZllVcx6U15THstcvp6 von1Skkanc0vwMrvJtWvP5tkELpd5ktglb9IPwlXXPLDJ/4ow5Ufq6trpWO9j9Gj 2coaM/J9IfaZKX9Abb/t =VdOw -----END PGP SIGNATURE----- --u3/rZRmxL6MmkK24--