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charset=\"utf-8\"","Content-Transfer-Encoding":"8bit","Received-SPF":"pass client-ip=170.10.133.124; envelope-from=armenon@redhat.com;\n helo=us-smtp-delivery-124.mimecast.com","X-Spam_score_int":"-25","X-Spam_score":"-2.6","X-Spam_bar":"--","X-Spam_report":"(-2.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.54,\n DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1,\n RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H2=0.001,\n RCVD_IN_VALIDITY_RPBL_BLOCKED=0.001, RCVD_IN_VALIDITY_SAFE_BLOCKED=0.001,\n SPF_HELO_PASS=-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-Unsubscribe":",\n ","List-Archive":"","List-Post":"","List-Help":"","List-Subscribe":",\n ","Errors-To":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org","Sender":"qemu-devel-bounces+incoming=patchwork.ozlabs.org@nongnu.org"},"content":"In GLib, GByteArray is an object managed by the library. Currently,\nmigrating a GByteArray requires treating it as a raw C struct and using\nVMSTATE_VBUFFER_ALLOC_UINT32. For example, see vmstate_vdba in\nui/vdagent.c\n\nQEMU cannot pretend that GByteArray is a C struct and simply use\nVMS_ALLOC to g_malloc() the buffer. This is because, VMS_ALLOC blindly\noverwrites the data pointer with a newly allocated buffer, thereby\nleaking the previous memory. Besides, GLib tracks the array's capacity\nin a hidden alloc field. Bypassing GLib APIs leave this capacity out of\nsync with the newly allocated buffer, potentially leading to heap buffer\noverflows during subsequent g_byte_array_append() calls.\n\nThis series adds a new VMState called VMSTATE_GBYTEARRAY, which will\ndirectly use GLib library API calls to create, or resize the object.\nThis is then used in ui/vdaagent.c replacing the use of\nVMSTATE_VBUFFER_ALLOC_UINT32.\n\nChanges in v2:\n- Marc-André pointed out the problem of not updating the device state\n itself. To do that we should essentially pass a pointer to the\n GByteArray pointer. Remove VMS_POINTER from VMSTATE_GBYTEARRAY. This\n changes 'pv' to be the address of the pointer field (GByteArray **)\n instead of the pointer's value.\n- Update get_g_byte_array and put_g_byte_array to handle this additional\n level of indirection, allowing safe allocation and updating device state.\n- Link to v1: https://lore.kernel.org/all/20260406115247.4879-1-armenon@redhat.com/\n\nArun Menon (2):\n migration/vmstate: Add VMState support for GByteArray\n ui/vdagent: Use VMSTATE_GBYTEARRAY to safely migrate outbuf\n\n include/migration/vmstate.h | 10 ++++++++++\n migration/vmstate-types.c | 37 +++++++++++++++++++++++++++++++++++++\n ui/vdagent.c | 13 +------------\n 3 files changed, 48 insertions(+), 12 deletions(-)"}