On Wed, Feb 08, 2023 at 09:35:58AM +0000, Het Gala wrote: > In existing senario, 'migrate' QAPI argument - string uri, is encoded > twice to extract migration parameters for stream connection. This is > not a good representation of migration wire protocol as it is a data > encoding scheme within a data encoding scheme. Qemu should be able to > directly work with results from QAPI without having to do a second > level parsing. > Modified 'migrate' QAPI design supports well defined MigrateChannel > struct which plays important role in avoiding double encoding > of uri strings. > > qemu_uri_parsing() parses uri string (kept for backward > compatibility) and populate the MigrateChannel struct parameters. > Migration code flow for all required migration transport types - > socket, exec and rdma is modified. > > Suggested-by: Daniel P. Berrange <berra...@redhat.com> > Suggested-by: Manish Mishra <manish.mis...@nutanix.com> > Suggested-by: Aravind Retnakaran <aravind.retnaka...@nutanix.com> > Signed-off-by: Het Gala <het.g...@nutanix.com> > --- > migration/exec.c | 31 ++++++++++++++++-- > migration/exec.h | 4 ++- > migration/migration.c | 75 +++++++++++++++++++++++++++++++++++-------- > migration/rdma.c | 30 +++++------------ > migration/rdma.h | 3 +- > migration/socket.c | 21 ++++-------- > migration/socket.h | 3 +- > 7 files changed, 110 insertions(+), 57 deletions(-) > > diff --git a/migration/exec.c b/migration/exec.c > index 375d2e1b54..4fa9819792 100644 > --- a/migration/exec.c > +++ b/migration/exec.c > @@ -23,14 +23,39 @@ > #include "migration.h" > #include "io/channel-command.h" > #include "trace.h" > +#include "qapi/error.h" > > > -void exec_start_outgoing_migration(MigrationState *s, const char *command, > Error **errp) > +void init_exec_array(strList *command, const char *argv[], Error **errp) > +{ > + int i = 0; > + strList *lst; > + > + for (lst = command; lst ; lst = lst->next) { > + argv[i++] = lst->value; > + } > + > + /* > + * Considering exec command always has 3 arguments to execute > + * a command directly from the bash itself. > + */ > + if (i > 3) { > + error_setg(errp, "exec accepts maximum of 3 arguments in the list"); > + return; > + }
By the time this check fires, the for() loop above has already done out of bounds writes on argv[]. > + > + argv[i] = NULL; > + return; > +} > + > +void exec_start_outgoing_migration(MigrationState *s, strList *command, > + Error **errp) > { > QIOChannel *ioc; > - const char *argv[] = { "/bin/sh", "-c", command, NULL }; > + const char *argv[4]; > + init_exec_array(command, argv, errp); If someone invokes 'migrate' with the old URI style, the strList will be 3 elements, and thus argv[4] is safe. If someone invokes 'migrate' with thue new MigrateChannel style, the strList can be arbitrarily long and thus argv[4] will be risk of overflow. > > - trace_migration_exec_outgoing(command); > + trace_migration_exec_outgoing(argv[2]); > ioc = QIO_CHANNEL(qio_channel_command_new_spawn(argv, > O_RDWR, > errp)); > diff --git a/migration/exec.h b/migration/exec.h > index b210ffde7a..5b39ba6cbb 100644 > --- a/migration/exec.h > +++ b/migration/exec.h > @@ -19,8 +19,10 @@ > > #ifndef QEMU_MIGRATION_EXEC_H > #define QEMU_MIGRATION_EXEC_H > +void init_exec_array(strList *command, const char *argv[], Error **errp); > + > void exec_start_incoming_migration(const char *host_port, Error **errp); > > -void exec_start_outgoing_migration(MigrationState *s, const char *host_port, > +void exec_start_outgoing_migration(MigrationState *s, strList *host_port, > Error **errp); > #endif > diff --git a/migration/migration.c b/migration/migration.c > index f6dd8dbb03..accbf72a18 100644 > --- a/migration/migration.c > +++ b/migration/migration.c > @@ -63,6 +63,7 @@ > #include "sysemu/cpus.h" > #include "yank_functions.h" > #include "sysemu/qtest.h" > +#include "qemu/sockets.h" > #include "ui/qemu-spice.h" > > #define MAX_THROTTLE (128 << 20) /* Migration transfer speed > throttling */ > @@ -489,6 +490,44 @@ void migrate_add_address(SocketAddress *address) > QAPI_CLONE(SocketAddress, address)); > } > > +static bool migrate_uri_parse(const char *uri, > + MigrateChannel **channel, > + Error **errp) > +{ > + Error *local_err = NULL; > + MigrateChannel *val = g_new0(MigrateChannel, 1); > + MigrateAddress *addrs = g_new0(MigrateAddress, 1); > + SocketAddress *saddr = g_new0(SocketAddress, 1); > + InetSocketAddress *isock = g_new0(InetSocketAddress, 1); > + > + if (strstart(uri, "exec:", NULL)) { > + addrs->transport = MIGRATE_TRANSPORT_EXEC; > + addrs->u.exec.data = str_split_at_comma(uri + strlen("exec:")); > + } else if (strstart(uri, "rdma:", NULL) && > + !inet_parse(isock, uri + strlen("rdma:"), errp)) { > + addrs->transport = MIGRATE_TRANSPORT_RDMA; > + addrs->u.rdma.data = isock; > + } else if (strstart(uri, "tcp:", NULL) || > + strstart(uri, "unix:", NULL) || > + strstart(uri, "vsock:", NULL) || > + strstart(uri, "fd:", NULL)) { > + addrs->transport = MIGRATE_TRANSPORT_SOCKET; > + saddr = socket_parse(uri, &local_err); > + addrs->u.socket.socket_type = saddr; > + } > + > + val->channeltype = MIGRATE_CHANNEL_TYPE_MAIN; > + val->addr = addrs; > + *channel = val; > + > + if (local_err) { > + error_propagate(errp, local_err); > + return false; > + } > + > + return true; > +} > + > static void qemu_start_incoming_migration(const char *uri, Error **errp) > { > const char *p = NULL; > @@ -2469,7 +2508,8 @@ void qmp_migrate(const char *uri, MigrateChannel > *channel, bool has_blk, > { > Error *local_err = NULL; > MigrationState *s = migrate_get_current(); > - const char *p = NULL; > + MigrateAddress *addrs = g_new0(MigrateAddress, 1); > + SocketAddress *saddr = g_new0(SocketAddress, 1); > > if (!migrate_prepare(s, has_blk && blk, has_inc && inc, > has_resume && resume, errp)) { > @@ -2490,22 +2530,29 @@ void qmp_migrate(const char *uri, MigrateChannel > *channel, bool has_blk, > error_setg(errp, "uri and channels options should be" > "mutually exclusive"); > return; > + } else if (uri && !migrate_uri_parse(uri, &channel, &local_err)) { > + error_setg(errp, "Error parsing uri"); > + return; > } > > migrate_protocol_allow_multi_channels(false); > - if (strstart(uri, "tcp:", &p) || > - strstart(uri, "unix:", NULL) || > - strstart(uri, "vsock:", NULL)) { > - migrate_protocol_allow_multi_channels(true); > - socket_start_outgoing_migration(s, p ? p : uri, &local_err); > -#ifdef CONFIG_RDMA > - } else if (strstart(uri, "rdma:", &p)) { > - rdma_start_outgoing_migration(s, p, &local_err); > -#endif > - } else if (strstart(uri, "exec:", &p)) { > - exec_start_outgoing_migration(s, p, &local_err); > - } else if (strstart(uri, "fd:", &p)) { > - fd_start_outgoing_migration(s, p, &local_err); > + addrs = channel->addr; > + saddr = channel->addr->u.socket.socket_type; > + if (addrs->transport == MIGRATE_TRANSPORT_SOCKET) { > + if (saddr->type == SOCKET_ADDRESS_TYPE_INET || > + saddr->type == SOCKET_ADDRESS_TYPE_UNIX || > + saddr->type == SOCKET_ADDRESS_TYPE_VSOCK) { > + migrate_protocol_allow_multi_channels(true); > + socket_start_outgoing_migration(s, saddr, &local_err); > + } else if (saddr->type == SOCKET_ADDRESS_TYPE_FD) { > + fd_start_outgoing_migration(s, saddr->u.fd.str, &local_err); > + } > + #ifdef CONFIG_RDMA > + } else if (addrs->transport == MIGRATE_TRANSPORT_RDMA) { > + rdma_start_outgoing_migration(s, addrs->u.rdma.data, &local_err); > + #endif > + } else if (addrs->transport == MIGRATE_TRANSPORT_EXEC) { > + exec_start_outgoing_migration(s, addrs->u.exec.data, &local_err); > } else { > if (!(has_resume && resume)) { > yank_unregister_instance(MIGRATION_YANK_INSTANCE); > diff --git a/migration/rdma.c b/migration/rdma.c > index 288eadc2d2..48f49add6f 100644 > --- a/migration/rdma.c > +++ b/migration/rdma.c > @@ -316,7 +316,6 @@ typedef struct RDMALocalBlocks { > typedef struct RDMAContext { > char *host; > int port; > - char *host_port; > > RDMAWorkRequestData wr_data[RDMA_WRID_MAX]; > > @@ -2449,9 +2448,7 @@ static void qemu_rdma_cleanup(RDMAContext *rdma) > rdma->channel = NULL; > } > g_free(rdma->host); > - g_free(rdma->host_port); > rdma->host = NULL; > - rdma->host_port = NULL; > } > > > @@ -2733,28 +2730,17 @@ static void > qemu_rdma_return_path_dest_init(RDMAContext *rdma_return_path, > rdma_return_path->is_return_path = true; > } > > -static void *qemu_rdma_data_init(const char *host_port, Error **errp) > +static void *qemu_rdma_data_init(InetSocketAddress *saddr, Error **errp) > { > RDMAContext *rdma = NULL; > - InetSocketAddress *addr; > > - if (host_port) { > + if (saddr) { > rdma = g_new0(RDMAContext, 1); > rdma->current_index = -1; > rdma->current_chunk = -1; > > - addr = g_new(InetSocketAddress, 1); > - if (!inet_parse(addr, host_port, NULL)) { > - rdma->port = atoi(addr->port); > - rdma->host = g_strdup(addr->host); > - rdma->host_port = g_strdup(host_port); > - } else { > - ERROR(errp, "bad RDMA migration address '%s'", host_port); > - g_free(rdma); > - rdma = NULL; > - } > - > - qapi_free_InetSocketAddress(addr); > + rdma->host = g_strdup(saddr->host); > + rdma->port = atoi(saddr->port); > } > > return rdma; > @@ -3354,6 +3340,7 @@ static int qemu_rdma_accept(RDMAContext *rdma) > .private_data_len = sizeof(cap), > }; > RDMAContext *rdma_return_path = NULL; > + InetSocketAddress *isock = g_new0(InetSocketAddress, 1); > struct rdma_cm_event *cm_event; > struct ibv_context *verbs; > int ret = -EINVAL; > @@ -4152,14 +4139,13 @@ err: > error_propagate(errp, local_err); > if (rdma) { > g_free(rdma->host); > - g_free(rdma->host_port); > } > g_free(rdma); > g_free(rdma_return_path); > } > > void rdma_start_outgoing_migration(void *opaque, > - const char *host_port, Error **errp) > + InetSocketAddress *addr, Error **errp) > { > MigrationState *s = opaque; > RDMAContext *rdma_return_path = NULL; > @@ -4172,7 +4158,7 @@ void rdma_start_outgoing_migration(void *opaque, > return; > } > > - rdma = qemu_rdma_data_init(host_port, errp); > + rdma = qemu_rdma_data_init(addr, errp); > if (rdma == NULL) { > goto err; > } > @@ -4193,7 +4179,7 @@ void rdma_start_outgoing_migration(void *opaque, > > /* RDMA postcopy need a separate queue pair for return path */ > if (migrate_postcopy()) { > - rdma_return_path = qemu_rdma_data_init(host_port, errp); > + rdma_return_path = qemu_rdma_data_init(addr, errp); > > if (rdma_return_path == NULL) { > goto return_path_err; > diff --git a/migration/rdma.h b/migration/rdma.h > index de2ba09dc5..8d9978e1a9 100644 > --- a/migration/rdma.h > +++ b/migration/rdma.h > @@ -13,11 +13,12 @@ > * later. See the COPYING file in the top-level directory. > * > */ > +#include "io/channel-socket.h" > > #ifndef QEMU_MIGRATION_RDMA_H > #define QEMU_MIGRATION_RDMA_H > > -void rdma_start_outgoing_migration(void *opaque, const char *host_port, > +void rdma_start_outgoing_migration(void *opaque, InetSocketAddress *addr, > Error **errp); > > void rdma_start_incoming_migration(const char *host_port, Error **errp); > diff --git a/migration/socket.c b/migration/socket.c > index e6fdf3c5e1..c751e0bfc1 100644 > --- a/migration/socket.c > +++ b/migration/socket.c > @@ -27,6 +27,8 @@ > #include "io/net-listener.h" > #include "trace.h" > #include "postcopy-ram.h" > +#include "qapi/clone-visitor.h" > +#include "qapi/qapi-visit-sockets.h" > > struct SocketOutgoingArgs { > SocketAddress *saddr; > @@ -107,19 +109,20 @@ out: > object_unref(OBJECT(sioc)); > } > > -static void > -socket_start_outgoing_migration_internal(MigrationState *s, > +void socket_start_outgoing_migration(MigrationState *s, > SocketAddress *saddr, > Error **errp) > { > QIOChannelSocket *sioc = qio_channel_socket_new(); > struct SocketConnectData *data = g_new0(struct SocketConnectData, 1); > + SocketAddress *addr = g_new0(SocketAddress, 1); > + addr = QAPI_CLONE(SocketAddress, saddr); > > data->s = s; > > /* in case previous migration leaked it */ > qapi_free_SocketAddress(outgoing_args.saddr); > - outgoing_args.saddr = saddr; > + outgoing_args.saddr = addr; > > if (saddr->type == SOCKET_ADDRESS_TYPE_INET) { > data->hostname = g_strdup(saddr->u.inet.host); > @@ -134,18 +137,6 @@ socket_start_outgoing_migration_internal(MigrationState > *s, > NULL); > } > > -void socket_start_outgoing_migration(MigrationState *s, > - const char *str, > - Error **errp) > -{ > - Error *err = NULL; > - SocketAddress *saddr = socket_parse(str, &err); > - if (!err) { > - socket_start_outgoing_migration_internal(s, saddr, &err); > - } > - error_propagate(errp, err); > -} > - > static void socket_accept_incoming_migration(QIONetListener *listener, > QIOChannelSocket *cioc, > gpointer opaque) > diff --git a/migration/socket.h b/migration/socket.h > index dc54df4e6c..95c9c166ec 100644 > --- a/migration/socket.h > +++ b/migration/socket.h > @@ -19,6 +19,7 @@ > > #include "io/channel.h" > #include "io/task.h" > +#include "io/channel-socket.h" > > void socket_send_channel_create(QIOTaskFunc f, void *data); > QIOChannel *socket_send_channel_create_sync(Error **errp); > @@ -26,6 +27,6 @@ int socket_send_channel_destroy(QIOChannel *send); > > void socket_start_incoming_migration(const char *str, Error **errp); > > -void socket_start_outgoing_migration(MigrationState *s, const char *str, > +void socket_start_outgoing_migration(MigrationState *s, SocketAddress *saddr, > Error **errp); > #endif > -- > 2.22.3 > With regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|