On Fri, Feb 14, 2025 at 11:10:03PM +0100, Martin Wilck wrote:
> Create a static new helper function which is used by both libmpathcmd
> and libmpathutil and fills in the socket address name from the compile-time
> default. The function is able to handle both abstract and pathname sockets,
> but more changes are needed to make the latter actually work.
>
> Signed-off-by: Martin Wilck <mwilck@xxxxxxxx>
> ---
> .gitignore | 1 +
> Makefile.inc | 7 ++--
> create-config.mk | 1 +
> libmpathcmd/mpath_cmd.c | 11 ++-----
> libmpathcmd/mpath_fill_sockaddr.c | 32 +++++++++++++++++++
> libmpathutil/uxsock.c | 15 ++++-----
> multipathd/Makefile | 4 +--
> ...multipathd.socket => multipathd.socket.in} | 2 +-
> 8 files changed, 51 insertions(+), 22 deletions(-)
> create mode 100644 libmpathcmd/mpath_fill_sockaddr.c
> rename multipathd/{multipathd.socket => multipathd.socket.in} (87%)
>
> diff --git a/.gitignore b/.gitignore
> index 4548cfb..6a1f6fc 100644
> --- a/.gitignore
> +++ b/.gitignore
> @@ -24,6 +24,7 @@ multipathd/multipathd
> multipathd/multipathd.8
> multipathd/multipathc
> multipathd/multipathd.service
> +multipathd/multipathd.socket
> mpathpersist/mpathpersist
> mpathpersist/mpathpersist.8
> abi.tar.gz
> diff --git a/Makefile.inc b/Makefile.inc
> index 76efeb9..4015006 100644
> --- a/Makefile.inc
> +++ b/Makefile.inc
> @@ -79,7 +79,7 @@ libudev_incdir := $(or $(shell $(PKG_CONFIG) --variable=includedir libudev),/usr
> kernel_incdir := /usr/include
> sysdir_bin := $(sys_execprefix)bin
>
> -abstract_socket := /org/kernel/linux/storage/multipathd
> +abstract_socket := @/org/kernel/linux/storage/multipathd
>
> ifeq ($(V),)
> Q := @
> @@ -117,7 +117,9 @@ CPPFLAGS := $(FORTIFY_OPT) $(CPPFLAGS) $(D_URCU_VERSION) \
> -DRUNTIME_DIR=\"$(runtimedir)\" -DCONFIG_DIR=\"$(TGTDIR)$(configdir)\" \
> -DDEFAULT_CONFIGFILE=\"$(TGTDIR)$(configfile)\" -DSTATE_DIR=\"$(TGTDIR)$(statedir)\" \
> -DEXTRAVERSION=\"$(EXTRAVERSION)\" \
> - -DDEFAULT_SOCKET=\"$(abstract_socket)\" -MMD -MP
> + -DDEFAULT_SOCKET=\"$(abstract_socket)\" \
> + -DWSTRINGOP_TRUNCATION=$(if $(WSTRINGOP_TRUNCATION),1,0) \
> + -MMD -MP
> CFLAGS := -std=$(C_STD) $(CFLAGS) $(OPTFLAGS) $(WARNFLAGS) -pipe \
> -fexceptions
> BIN_CFLAGS := -fPIE -DPIE
> @@ -170,4 +172,5 @@ NV_VERSION_SCRIPT = $(DEVLIB:%.so=%-nv.version)
> -e 's:@SYSDIR_BIN@:'$(sysdir_bin)': g' \
> -e 's:@RUNTIME_DIR@:'$(runtimedir)':g' \
> -e 's/@MODPROBE_UNIT@/'$(MODPROBE_UNIT)'/g' \
> + -e 's,@MPATH_SOCKET@,'$(abstract_socket)',g' \
> $< >$@
> diff --git a/create-config.mk b/create-config.mk
> index ab163ed..f05fdab 100644
> --- a/create-config.mk
> +++ b/create-config.mk
> @@ -191,6 +191,7 @@ $(TOPDIR)/config.mk: $(multipathdir)/autoconfig.h
> @echo "ERROR_DISCARDED_QUALIFIERS := $(call TEST_CC_OPTION,-Werror=discarded-qualifiers,)" >>$@
> @echo "WNOCLOBBERED := $(call TEST_CC_OPTION,-Wno-clobbered -Wno-error=clobbered,)" >>$@
> @echo "WFORMATOVERFLOW := $(call TEST_CC_OPTION,-Wformat-overflow=2,)" >>$@
> + @echo "WSTRINGOP_TRUNCATION := $(call TEST_CC_OPTION,-Wstringop-truncation)" >>$@
> @echo "W_MISSING_INITIALIZERS := $(call TEST_MISSING_INITIALIZERS)" >>$@
> @echo "W_URCU_TYPE_LIMITS := $(call TEST_URCU_TYPE_LIMITS)" >>$@
> @echo "ENABLE_LIBDMMP := $(ENABLE_LIBDMMP)" >>$@
> diff --git a/libmpathcmd/mpath_cmd.c b/libmpathcmd/mpath_cmd.c
> index a38e8b6..5a39471 100644
> --- a/libmpathcmd/mpath_cmd.c
> +++ b/libmpathcmd/mpath_cmd.c
> @@ -24,11 +24,13 @@
> #include <sys/socket.h>
> #include <sys/un.h>
> #include <poll.h>
> +#include <stddef.h>
> #include <string.h>
> #include <errno.h>
> #include <fcntl.h>
>
> #include "mpath_cmd.h"
> +#include "mpath_fill_sockaddr.c"
>
> /*
> * keep reading until its all read
> @@ -101,14 +103,6 @@ int mpath_connect__(int nonblocking)
> struct sockaddr_un addr;
> int flags = 0;
>
> - memset(&addr, 0, sizeof(addr));
> - addr.sun_family = AF_LOCAL;
> - addr.sun_path[0] = '\0';
> - strncpy(&addr.sun_path[1], DEFAULT_SOCKET, sizeof(addr.sun_path) - 1);
> - len = strlen(DEFAULT_SOCKET) + 1 + sizeof(sa_family_t);
> - if (len > sizeof(struct sockaddr_un))
> - len = sizeof(struct sockaddr_un);
> -
> fd = socket(AF_LOCAL, SOCK_STREAM, 0);
> if (fd == -1)
> return -1;
> @@ -119,6 +113,7 @@ int mpath_connect__(int nonblocking)
> (void)fcntl(fd, F_SETFL, flags|O_NONBLOCK);
> }
>
> + len = mpath_fill_sockaddr__(&addr, DEFAULT_SOCKET);
> if (connect(fd, (struct sockaddr *)&addr, len) == -1) {
> int err = errno;
>
> diff --git a/libmpathcmd/mpath_fill_sockaddr.c b/libmpathcmd/mpath_fill_sockaddr.c
> new file mode 100644
> index 0000000..750ef3e
> --- /dev/null
> +++ b/libmpathcmd/mpath_fill_sockaddr.c
> @@ -0,0 +1,32 @@
> +/*
> + * Copyright (c) 2025 SUSE LLC
> + * SPDX-license-identifier: LGPL-2.1-or-newer
> + */
> +
> +static size_t mpath_fill_sockaddr__(struct sockaddr_un *addr, const char *name)
> +{
> + size_t len;
> +
> + addr->sun_family = AF_LOCAL;
> +
> + if (name[0] != '@') {
> + /* Pathname socket. This should be NULL-terminated. */
> + strncpy(&addr->sun_path[0], name, sizeof(addr->sun_path) - 1);
> + addr->sun_path[sizeof(addr->sun_path) - 1] = '\0';
> + len = offsetof(struct sockaddr_un, sun_path) + strlen(name) + 1;
> + } else {
> + addr->sun_path[0] = '\0';
> + /*
Nitpick: These comment lines are needlessly longer than 80 characters,
but otherwise, everything's fine.
Reviewed-by: Benjamin Marzinski <bmarzins@xxxxxxxxxx>
> + * The abstract socket's name doesn't need to be NULL terminated.
> + * Actually, a trailing NULL would be considered part of the socket name.
> + */
> +#pragma GCC diagnostic push
> +#if WSTRINGOP_TRUNCATION
> +#pragma GCC diagnostic ignored "-Wstringop-truncation"
> +#endif
> + strncpy(&addr->sun_path[1], &name[1], sizeof(addr->sun_path) - 1);
> +#pragma GCC diagnostic pop
> + len = offsetof(struct sockaddr_un, sun_path) + strlen(name);
> + }
> + return len > sizeof(*addr) ? sizeof(*addr) : len;
> +}
> diff --git a/libmpathutil/uxsock.c b/libmpathutil/uxsock.c
> index 2135476..12c4608 100644
> --- a/libmpathutil/uxsock.c
> +++ b/libmpathutil/uxsock.c
> @@ -6,12 +6,15 @@
> */
> #include <stdio.h>
> #include <stdlib.h>
> +#include <string.h>
> #include <unistd.h>
> #include <stdarg.h>
> +#include <stddef.h>
> #include <fcntl.h>
> #include <sys/ioctl.h>
> #include <sys/types.h>
> #include <sys/socket.h>
> +#include <sys/stat.h>
> #include <sys/un.h>
> #include <poll.h>
> #include <signal.h>
> @@ -33,6 +36,8 @@
> static int _recv_packet(int fd, char **buf, unsigned int timeout,
> ssize_t limit);
>
> +#include "../libmpathcmd/mpath_fill_sockaddr.c"
> +
> /*
> * create a unix domain socket and start listening on it
> * return a file descriptor open on the socket
> @@ -63,15 +68,7 @@ int ux_socket_listen(const char *name)
> return -1;
> }
>
> - memset(&addr, 0, sizeof(addr));
> - addr.sun_family = AF_LOCAL;
> - addr.sun_path[0] = '\0';
> - len = strlen(name) + 1;
> - if (len >= sizeof(addr.sun_path))
> - len = sizeof(addr.sun_path) - 1;
> - memcpy(&addr.sun_path[1], name, len);
> -
> - len += sizeof(sa_family_t);
> + len = mpath_fill_sockaddr__(&addr, name);
> if (bind(fd, (struct sockaddr *)&addr, len) == -1) {
> condlog(3, "Couldn't bind to ux_socket, error %d", errno);
> close(fd);
> diff --git a/multipathd/Makefile b/multipathd/Makefile
> index 997b40c..61cf1af 100644
> --- a/multipathd/Makefile
> +++ b/multipathd/Makefile
> @@ -41,7 +41,7 @@ ifeq ($(FPIN_SUPPORT),1)
> OBJS += fpin_handlers.o
> endif
>
> -all : $(EXEC) $(CLI) $(MANPAGES) $(EXEC).service
> +all : $(EXEC) $(CLI) $(MANPAGES) $(EXEC).service $(EXEC).socket
>
> $(EXEC): $(OBJS) $(multipathdir)/libmultipath.so $(mpathcmddir)/libmpathcmd.so
> @echo building $@ because of $?
> @@ -78,7 +78,7 @@ uninstall:
> $(Q)$(RM) $(DESTDIR)$(unitdir)/$(EXEC).socket
>
> clean: dep_clean
> - $(Q)$(RM) core *.o $(EXEC) $(CLI) $(MANPAGES) $(EXEC).service
> + $(Q)$(RM) core *.o $(EXEC) $(CLI) $(MANPAGES) $(EXEC).service $(EXEC).socket
>
> include $(wildcard $(OBJS:.o=.d) $(CLI_OBJS:.o=.d))
>
> diff --git a/multipathd/multipathd.socket b/multipathd/multipathd.socket.in
> similarity index 87%
> rename from multipathd/multipathd.socket
> rename to multipathd/multipathd.socket.in
> index 6a62f5f..c0e86c3 100644
> --- a/multipathd/multipathd.socket
> +++ b/multipathd/multipathd.socket.in
> @@ -7,7 +7,7 @@ ConditionVirtualization=!container
> Before=sockets.target
>
> [Socket]
> -ListenStream=@/org/kernel/linux/storage/multipathd
> +ListenStream=@MPATH_SOCKET@
>
> [Install]
> # Socket activation for multipathd is disabled by default.
> --
> 2.48.1
