--- a/arch/um/drivers/mconsole_kern.c 2008-07-13 23:51:29.000000000 +0200 +++ b/arch/um/drivers/mconsole_kern.c 2008-08-06 09:32:52.000000000 +0200 @@ -4,6 +4,7 @@ * Licensed under the GPL */ +#include "linux/kmod.h" #include #include #include @@ -18,6 +19,8 @@ #include #include #include +#include +#include #include #include "init.h" @@ -199,6 +202,65 @@ } #endif +void mconsole_exec(struct mc_request *req) +{ + DECLARE_COMPLETION_ONSTACK(done); + struct subprocess_info *sub_info; + int res, len; + struct file *out; + char buf[MCONSOLE_MAX_DATA]; + + char *envp[] = { + "HOME=/", "TERM=linux", + "PATH=/sbin:/bin:/usr/sbin:/usr/bin:/usr/local/sbin:/usr/local/bin", + NULL + }; + char *argv[] = { + "/bin/sh", "-c", + req->request.data + strlen("exec "), + NULL + }; + + sub_info = call_usermodehelper_setup("/bin/sh", argv, envp); + if (sub_info == NULL) { + mconsole_reply(req, "call_usermodehelper_setup failed", 1, 0); + return; + } + res = call_usermodehelper_stdoutpipe(sub_info, &out); + if (res < 0) { + call_usermodehelper_freeinfo(sub_info); + mconsole_reply(req, "call_usermodehelper_stdoutpipe failed", 1, 0); + return; + } + + call_usermodehelper_setcomplete(sub_info, &done); + + res = call_usermodehelper_exec(sub_info, UMH_WAIT_EXT); + if (res < 0) { + call_usermodehelper_freeinfo(sub_info); + mconsole_reply(req, "call_usermodehelper_exec failed", 1, 0); + return; + } + + for (;;) { + len = out->f_op->read(out, buf, sizeof(buf), 0); + if (len < 0) { + mconsole_reply(req, "reading output failed", 1, 0); + break; + } + if (len == 0) + break; + mconsole_reply_len(req, buf, len, 0, 1); + } + fput(out); + + wait_for_completion(&done); + res = call_usermodehelper_getretval(sub_info) >> 8; + call_usermodehelper_freeinfo(sub_info); + + mconsole_reply_len(req, buf, len, res, 0); +} + void mconsole_proc(struct mc_request *req) { char path[64]; @@ -270,6 +332,7 @@ stop - pause the UML; it will do nothing until it receives a 'go' \n\ go - continue the UML after a 'stop' \n\ log - make UML enter into the kernel log\n\ + exec - pass to /bin/sh -c synchronously\n\ proc - returns the contents of the UML's /proc/\n\ stack - returns the stack of the specified pid\n\ " --- a/arch/um/drivers/mconsole_user.c 2008-07-13 23:51:29.000000000 +0200 +++ b/arch/um/drivers/mconsole_user.c 2008-07-15 15:41:54.000000000 +0200 @@ -32,6 +32,7 @@ { "stop", mconsole_stop, MCONSOLE_PROC }, { "go", mconsole_go, MCONSOLE_INTR }, { "log", mconsole_log, MCONSOLE_INTR }, + { "exec", mconsole_exec, MCONSOLE_PROC }, { "proc", mconsole_proc, MCONSOLE_PROC }, { "stack", mconsole_stack, MCONSOLE_INTR }, }; --- a/arch/um/include/mconsole.h 2008-07-13 23:51:29.000000000 +0200 +++ b/arch/um/include/mconsole.h 2008-07-15 15:41:54.000000000 +0200 @@ -85,6 +85,7 @@ extern void mconsole_stop(struct mc_request *req); extern void mconsole_go(struct mc_request *req); extern void mconsole_log(struct mc_request *req); +extern void mconsole_exec(struct mc_request *req); extern void mconsole_proc(struct mc_request *req); extern void mconsole_stack(struct mc_request *req); --- a/kernel/kmod.c 2008-07-13 23:51:29.000000000 +0200 +++ b/kernel/kmod.c 2008-07-31 14:46:31.000000000 +0200 @@ -118,6 +118,7 @@ struct subprocess_info { struct work_struct work; struct completion *complete; + struct completion *executed; char *path; char **argv; char **envp; @@ -125,6 +126,7 @@ enum umh_wait wait; int retval; struct file *stdin; + struct file *stdout; void (*cleanup)(char **argv, char **envp); }; @@ -160,8 +162,26 @@ FD_SET(0, fdt->open_fds); FD_CLR(0, fdt->close_on_exec); spin_unlock(&f->file_lock); - - /* and disallow core files too */ + } + if (sub_info->stdout) { + struct files_struct *f = current->files; + struct fdtable *fdt; + + sys_close(1); + sys_close(2); + get_file(sub_info->stdout); + fd_install(1, sub_info->stdout); + fd_install(2, sub_info->stdout); + spin_lock(&f->file_lock); + fdt = files_fdtable(f); + FD_SET(1, fdt->open_fds); + FD_CLR(1, fdt->close_on_exec); + FD_SET(2, fdt->open_fds); + FD_CLR(2, fdt->close_on_exec); + spin_unlock(&f->file_lock); + } + if (sub_info->stdin || sub_info->stdout) { + /* disallow core files */ current->signal->rlim[RLIMIT_CORE] = (struct rlimit){0, 0}; } @@ -243,7 +263,7 @@ /* CLONE_VFORK: wait until the usermode helper has execve'd * successfully We need the data structures to stay around * until that is done. */ - if (wait == UMH_WAIT_PROC || wait == UMH_NO_WAIT) + if (wait == UMH_WAIT_PROC || wait == UMH_NO_WAIT || wait == UMH_WAIT_EXT) pid = kernel_thread(wait_for_helper, sub_info, CLONE_FS | CLONE_FILES | SIGCHLD); else @@ -254,6 +274,16 @@ case UMH_NO_WAIT: break; + case UMH_WAIT_EXT: + if (pid > 0) { + complete(sub_info->executed); + break; + } + sub_info->retval = pid; + complete(sub_info->executed); + complete(sub_info->complete); + break; + case UMH_WAIT_PROC: if (pid > 0) break; @@ -404,6 +434,19 @@ } EXPORT_SYMBOL(call_usermodehelper_setcleanup); +void call_usermodehelper_setcomplete(struct subprocess_info *info, + struct completion* complete) +{ + info->complete = complete; +} +EXPORT_SYMBOL(call_usermodehelper_setcomplete); + +int call_usermodehelper_getretval(struct subprocess_info *info) +{ + return info->retval; +} +EXPORT_SYMBOL(call_usermodehelper_getretval); + /** * call_usermodehelper_stdinpipe - set up a pipe to be used for stdin * @sub_info: a subprocess_info returned by call_usermodehelper_setup @@ -433,6 +476,29 @@ } EXPORT_SYMBOL(call_usermodehelper_stdinpipe); +int call_usermodehelper_stdoutpipe(struct subprocess_info *sub_info, + struct file **filp) +{ + struct file *f; + + f = create_write_pipe(); + if (IS_ERR(f)) + return PTR_ERR(f); + sub_info->stdout = f; + + f = create_read_pipe(f); + if (IS_ERR(f)) { + free_write_pipe(sub_info->stdout); + sub_info->stdout = NULL; + return PTR_ERR(f); + } + *filp = f; + + return 0; +} +EXPORT_SYMBOL(call_usermodehelper_stdoutpipe); + + /** * call_usermodehelper_exec - start a usermode application * @sub_info: information about the subprocessa @@ -460,15 +526,22 @@ goto out; } - sub_info->complete = &done; + if (wait == UMH_WAIT_EXT) + sub_info->executed = &done; + else + sub_info->complete = &done; + sub_info->wait = wait; queue_work(khelper_wq, &sub_info->work); if (wait == UMH_NO_WAIT) /* task has freed sub_info */ goto unlock; + wait_for_completion(&done); - retval = sub_info->retval; + retval = sub_info->retval; + if (wait == UMH_WAIT_EXT) /* caller will free sub_info */ + goto unlock; out: call_usermodehelper_freeinfo(sub_info); unlock: --- a/include/linux/kmod.h 2008-07-13 23:51:29.000000000 +0200 +++ b/include/linux/kmod.h 2008-07-31 14:43:33.000000000 +0200 @@ -38,6 +38,7 @@ struct key; struct file; struct subprocess_info; +struct completion; /* Allocate a subprocess_info structure */ struct subprocess_info *call_usermodehelper_setup(char *path, @@ -48,13 +49,20 @@ struct key *session_keyring); int call_usermodehelper_stdinpipe(struct subprocess_info *sub_info, struct file **filp); +int call_usermodehelper_stdoutpipe(struct subprocess_info *sub_info, + struct file **filp); +void call_usermodehelper_setcomplete(struct subprocess_info *sub_info, + struct completion *complete); void call_usermodehelper_setcleanup(struct subprocess_info *info, void (*cleanup)(char **argv, char **envp)); +int call_usermodehelper_getretval(struct subprocess_info *sub_info); enum umh_wait { UMH_NO_WAIT = -1, /* don't wait at all */ UMH_WAIT_EXEC = 0, /* wait for the exec, but not the process */ UMH_WAIT_PROC = 1, /* wait for the process to complete */ + UMH_WAIT_EXT = 2, /* wait for the exec then return and signal + when the process is complete */ }; /* Actually execute the sub-process */ --- a/arch/um/Makefile 2008-07-13 23:51:29.000000000 +0200 +++ b/arch/um/Makefile 2008-07-15 16:27:02.000000000 +0200 @@ -77,6 +77,7 @@ KERNEL_DEFINES = $(strip -Derrno=kernel_errno -Dsigprocmask=kernel_sigprocmask \ -Dmktime=kernel_mktime $(ARCH_KERNEL_DEFINES)) KBUILD_CFLAGS += $(KERNEL_DEFINES) +KBUILD_CFLAGS += $(call cc-option,-fno-unit-at-a-time,) PHONY += linux --- a/arch/um/Makefile-i386 2008-07-13 23:51:29.000000000 +0200 +++ b/arch/um/Makefile-i386 2008-07-15 16:23:57.000000000 +0200 @@ -32,11 +32,4 @@ # an unresolved reference. cflags-y += -ffreestanding -# Disable unit-at-a-time mode on pre-gcc-4.0 compilers, it makes gcc use -# a lot more stack due to the lack of sharing of stacklots. Also, gcc -# 4.3.0 needs -funit-at-a-time for extern inline functions. -KBUILD_CFLAGS += $(shell if [ $(call cc-version) -lt 0400 ] ; then \ - echo $(call cc-option,-fno-unit-at-a-time); \ - else echo $(call cc-option,-funit-at-a-time); fi ;) - KBUILD_CFLAGS += $(cflags-y) --- a/arch/um/Makefile-x86_64 2008-07-13 23:51:29.000000000 +0200 +++ b/arch/um/Makefile-x86_64 2008-07-15 16:24:20.000000000 +0200 @@ -21,6 +21,3 @@ LINK-$(CONFIG_LD_SCRIPT_DYN) += -Wl,-rpath,/lib64 LINK-y += -m64 - -# Do unit-at-a-time unconditionally on x86_64, following the host -KBUILD_CFLAGS += $(call cc-option,-funit-at-a-time) --- a/arch/um/drivers/line.c 2008-07-13 23:51:29.000000000 +0200 +++ b/arch/um/drivers/line.c 2008-07-28 15:13:19.000000000 +0200 @@ -876,6 +876,6 @@ return base; } - snprintf(title, len, "%s (%s)", base, umid); + snprintf(title, len, "%s (%s)", umid, base); return title; }