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SUSE_INTERNAL_BYPASS(-9.00)[]; BAYES_HAM(-3.00)[100.00%]; NEURAL_HAM_LONG(-1.00)[-1.000]; NEURAL_HAM_SHORT(-0.20)[-1.000]; MIME_GOOD(-0.10)[text/plain]; MIME_TRACE(0.00)[0:+]; ARC_NA(0.00)[]; MISSING_XM_UA(0.00)[]; RCVD_VIA_SMTP_AUTH(0.00)[]; TO_DN_SOME(0.00)[]; RCVD_TLS_ALL(0.00)[]; MID_RHS_MATCH_FROM(0.00)[]; DKIM_SIGNED(0.00)[suse.de:s=susede2_rsa,suse.de:s=susede2_ed25519]; FROM_HAS_DN(0.00)[]; RCPT_COUNT_FIVE(0.00)[5]; FROM_EQ_ENVFROM(0.00)[]; TO_MATCH_ENVRCPT_ALL(0.00)[]; RCVD_COUNT_TWO(0.00)[2]; DBL_BLOCKED_OPENRESOLVER(0.00)[imap1.dmz-prg2.suse.org:helo, suse.de:email, linaro.org:email] X-Spam-Score: -13.30 Received-SPF: pass client-ip=2a07:de40:b251:101:10:150:64:2; envelope-from=farosas@suse.de; helo=smtp-out2.suse.de X-Spam_score_int: -20 X-Spam_score: -2.1 X-Spam_bar: -- X-Spam_report: (-2.1 / 5.0 requ) BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: qemu development List-Archive: List-Post: List-Help: List-Subscribe: , Sender: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org X-Spam-Status: No, score=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_PASS,SPF_PASS autolearn=no autolearn_force=no version=4.0.1 X-Spam-Checker-Version: SpamAssassin 4.0.1 (2024-03-26) on aws-us-west-2-korg-listserv-alma10-1 Peter Maydell writes: > On Tue, 27 Oct 2026 at 14:33, Fabiano Rosas wrote: >> >> Peter Maydell writes: >> >> > On Tue, 21 Jul 2026 at 14:15, Fabiano Rosas wrote: >> >> +* **migration/snapshots**. Migration failures and snapshot load >> >> + failures are considered part of normal operation as long as the >> >> + source virtual machine and savevm file, respectively, are still >> >> + functional. Aborting the QEMU process at the migration/snapshot >> >> + destination is similarly not considered a security issue. The >> >> + migration stream is assumed to be secure as long as the design >> >> + principles described in the Architecture section are held, in >> >> + which case plain manipulation of the stream is not considered as >> >> + an attack vector. >> > >> > Reading this (which is now in our docs), it seems unclear to me >> > about whether it intends to say that any and all bugs that can >> > be triggered only by manipulating the migration stream are outside >> > the security scope, or only some of them. >> > >> >> All of them, but we're talking specifically about feeding bad data into >> QEMU from the host level. >> >> > It says "plain manipulation of the stream is not considered as >> > an attack vector", which suggests "everything is out of scope". >> >> By "plain manipulation", we mean that if someone loads a compromised >> loadvm image or if they have access to the infrastructure and proceed to >> inject bytes into the migration stream that is considered out of the >> scope of what we considered a security issue. The premise is that >> migration is a special process that requires a secure network and the >> usage of encryption. If you migrate in plain text over the internet, >> that's on you. >> >> The other scenario, this one in scope, would be an attack that starts on >> the guest operating system and trips the migration code to cause an >> effect. This would be an indirect stream manipulation, if we want to >> call it that. > > Thanks. I think we could maybe make the text clearer. Here's my > suggestion, that splits out the cases into a set of bullet points: > > * **migration/snapshots**. The user must deploy QEMU following the > design principles described in the Architecture section to ensure > that the migration stream is secure. Plain manipulation of the stream > is not considered to be an attack vector. This means that: > * Migration failures and snapshot load failures are part of normal > operation; these are not bugs as long as the source virtual machine > or savevm file are still functional > * Aborts, crashes or misbehaviour of the destination QEMU due to > an externally manipulated migration stream are bugs, but not > security issues > * A crash of the destination QEMU that can be triggered by a guest > manipulating a device on the source QEMU before a migration may > be a security issue, if it meets the other criteria we document > for security issues > > How does that sound? > Looks good, thanks. I'll send a patch. > I think we should also: > > * add a subsection to the "Sensitive configurations" part of this > document at the bottom, that makes it clear that the user needs > to be careful about the migration stream and loadvm files > (to parallel the one that says "it's your job to lock down > monitor access") > * update the part at the to of the document that includes in > its list of untrusted entities "Network protocols (e.g. NBD, > live migration)" as this suggests the opposite of what the > later text says. I guess just delete "live migration" ? > Yes, this one has been coming up frequently. The point was to keep developers thinking about migration stream validation. But it's misleading, better to remove it. > We also have 15 or so existing bugs that are labelled "confidential" > but which are "crafted migration stream can exploit the destination > QEMU". Unless you object I'll mark all those as non-confidential > non-security issues. > Ack > thanks > -- PMM