X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=lib%2Fkobject_uevent.c;h=920a3ca6e2590ddc3d64950a729441758d0a5ce5;hb=d014d043869cdc591f3a33243d3481fa4479c2d0;hp=a1922765ff315dfe1a90879f567c82e08521eaa2;hpb=8a82472f86bf693b8e91ed56c9ca4f62fbbdcfa3;p=safe%2Fjmp%2Flinux-2.6 diff --git a/lib/kobject_uevent.c b/lib/kobject_uevent.c index a192276..920a3ca 100644 --- a/lib/kobject_uevent.c +++ b/lib/kobject_uevent.c @@ -15,153 +15,198 @@ */ #include +#include +#include +#include + #include #include #include -#include -#include #include -#define BUFFER_SIZE 2048 /* buffer for the variables */ -#define NUM_ENVP 32 /* number of env pointers */ -#if defined(CONFIG_HOTPLUG) u64 uevent_seqnum; -char uevent_helper[UEVENT_HELPER_PATH_LEN] = "/sbin/hotplug"; +char uevent_helper[UEVENT_HELPER_PATH_LEN] = CONFIG_UEVENT_HELPER_PATH; static DEFINE_SPINLOCK(sequence_lock); #if defined(CONFIG_NET) static struct sock *uevent_sock; #endif -static char *action_to_string(enum kobject_action action) +/* the strings here must match the enum in include/linux/kobject.h */ +static const char *kobject_actions[] = { + [KOBJ_ADD] = "add", + [KOBJ_REMOVE] = "remove", + [KOBJ_CHANGE] = "change", + [KOBJ_MOVE] = "move", + [KOBJ_ONLINE] = "online", + [KOBJ_OFFLINE] = "offline", +}; + +/** + * kobject_action_type - translate action string to numeric type + * + * @buf: buffer containing the action string, newline is ignored + * @len: length of buffer + * @type: pointer to the location to store the action type + * + * Returns 0 if the action string was recognized. + */ +int kobject_action_type(const char *buf, size_t count, + enum kobject_action *type) { - switch (action) { - case KOBJ_ADD: - return "add"; - case KOBJ_REMOVE: - return "remove"; - case KOBJ_CHANGE: - return "change"; - case KOBJ_MOUNT: - return "mount"; - case KOBJ_UMOUNT: - return "umount"; - case KOBJ_OFFLINE: - return "offline"; - case KOBJ_ONLINE: - return "online"; - case KOBJ_MOVE: - return "move"; - default: - return NULL; + enum kobject_action action; + int ret = -EINVAL; + + if (count && (buf[count-1] == '\n' || buf[count-1] == '\0')) + count--; + + if (!count) + goto out; + + for (action = 0; action < ARRAY_SIZE(kobject_actions); action++) { + if (strncmp(kobject_actions[action], buf, count) != 0) + continue; + if (kobject_actions[action][count] != '\0') + continue; + *type = action; + ret = 0; + break; } +out: + return ret; } /** * kobject_uevent_env - send an uevent with environmental data * - * @action: action that is happening (usually KOBJ_MOVE) + * @action: action that is happening * @kobj: struct kobject that the action is happening to * @envp_ext: pointer to environmental data + * + * Returns 0 if kobject_uevent() is completed with success or the + * corresponding error when it fails. */ -void kobject_uevent_env(struct kobject *kobj, enum kobject_action action, - char *envp_ext[]) +int kobject_uevent_env(struct kobject *kobj, enum kobject_action action, + char *envp_ext[]) { - char **envp; - char *buffer; - char *scratch; - const char *action_string; + struct kobj_uevent_env *env; + const char *action_string = kobject_actions[action]; const char *devpath = NULL; const char *subsystem; struct kobject *top_kobj; struct kset *kset; struct kset_uevent_ops *uevent_ops; u64 seq; - char *seq_buff; int i = 0; - int retval; - int j; + int retval = 0; - pr_debug("%s\n", __FUNCTION__); - - action_string = action_to_string(action); - if (!action_string) - return; + pr_debug("kobject: '%s' (%p): %s\n", + kobject_name(kobj), kobj, __func__); /* search the kset we belong to */ top_kobj = kobj; - if (!top_kobj->kset && top_kobj->parent) { - do { - top_kobj = top_kobj->parent; - } while (!top_kobj->kset && top_kobj->parent); + while (!top_kobj->kset && top_kobj->parent) + top_kobj = top_kobj->parent; + + if (!top_kobj->kset) { + pr_debug("kobject: '%s' (%p): %s: attempted to send uevent " + "without kset!\n", kobject_name(kobj), kobj, + __func__); + return -EINVAL; } - if (!top_kobj->kset) - return; kset = top_kobj->kset; uevent_ops = kset->uevent_ops; - /* skip the event, if the filter returns zero. */ + /* skip the event, if uevent_suppress is set*/ + if (kobj->uevent_suppress) { + pr_debug("kobject: '%s' (%p): %s: uevent_suppress " + "caused the event to drop!\n", + kobject_name(kobj), kobj, __func__); + return 0; + } + /* skip the event, if the filter returns zero. */ if (uevent_ops && uevent_ops->filter) - if (!uevent_ops->filter(kset, kobj)) - return; - - /* environment index */ - envp = kzalloc(NUM_ENVP * sizeof (char *), GFP_KERNEL); - if (!envp) - return; - - /* environment values */ - buffer = kmalloc(BUFFER_SIZE, GFP_KERNEL); - if (!buffer) - goto exit; - - /* complete object path */ - devpath = kobject_get_path(kobj, GFP_KERNEL); - if (!devpath) - goto exit; + if (!uevent_ops->filter(kset, kobj)) { + pr_debug("kobject: '%s' (%p): %s: filter function " + "caused the event to drop!\n", + kobject_name(kobj), kobj, __func__); + return 0; + } /* originating subsystem */ if (uevent_ops && uevent_ops->name) subsystem = uevent_ops->name(kset, kobj); else subsystem = kobject_name(&kset->kobj); + if (!subsystem) { + pr_debug("kobject: '%s' (%p): %s: unset subsystem caused the " + "event to drop!\n", kobject_name(kobj), kobj, + __func__); + return 0; + } + + /* environment buffer */ + env = kzalloc(sizeof(struct kobj_uevent_env), GFP_KERNEL); + if (!env) + return -ENOMEM; - /* event environemnt for helper process only */ - envp[i++] = "HOME=/"; - envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin"; + /* complete object path */ + devpath = kobject_get_path(kobj, GFP_KERNEL); + if (!devpath) { + retval = -ENOENT; + goto exit; + } /* default keys */ - scratch = buffer; - envp [i++] = scratch; - scratch += sprintf(scratch, "ACTION=%s", action_string) + 1; - envp [i++] = scratch; - scratch += sprintf (scratch, "DEVPATH=%s", devpath) + 1; - envp [i++] = scratch; - scratch += sprintf(scratch, "SUBSYSTEM=%s", subsystem) + 1; - for (j = 0; envp_ext && envp_ext[j]; j++) - envp[i++] = envp_ext[j]; - /* just reserve the space, overwrite it after kset call has returned */ - envp[i++] = seq_buff = scratch; - scratch += strlen("SEQNUM=18446744073709551616") + 1; + retval = add_uevent_var(env, "ACTION=%s", action_string); + if (retval) + goto exit; + retval = add_uevent_var(env, "DEVPATH=%s", devpath); + if (retval) + goto exit; + retval = add_uevent_var(env, "SUBSYSTEM=%s", subsystem); + if (retval) + goto exit; + + /* keys passed in from the caller */ + if (envp_ext) { + for (i = 0; envp_ext[i]; i++) { + retval = add_uevent_var(env, "%s", envp_ext[i]); + if (retval) + goto exit; + } + } /* let the kset specific function add its stuff */ if (uevent_ops && uevent_ops->uevent) { - retval = uevent_ops->uevent(kset, kobj, - &envp[i], NUM_ENVP - i, scratch, - BUFFER_SIZE - (scratch - buffer)); + retval = uevent_ops->uevent(kset, kobj, env); if (retval) { - pr_debug ("%s - uevent() returned %d\n", - __FUNCTION__, retval); + pr_debug("kobject: '%s' (%p): %s: uevent() returned " + "%d\n", kobject_name(kobj), kobj, + __func__, retval); goto exit; } } - /* we will send an event, request a new sequence number */ + /* + * Mark "add" and "remove" events in the object to ensure proper + * events to userspace during automatic cleanup. If the object did + * send an "add" event, "remove" will automatically generated by + * the core, if not already done by the caller. + */ + if (action == KOBJ_ADD) + kobj->state_add_uevent_sent = 1; + else if (action == KOBJ_REMOVE) + kobj->state_remove_uevent_sent = 1; + + /* we will send an event, so request a new sequence number */ spin_lock(&sequence_lock); seq = ++uevent_seqnum; spin_unlock(&sequence_lock); - sprintf(seq_buff, "SEQNUM=%llu", (unsigned long long)seq); + retval = add_uevent_var(env, "SEQNUM=%llu", (unsigned long long)seq); + if (retval) + goto exit; #if defined(CONFIG_NET) /* send netlink message */ @@ -171,22 +216,29 @@ void kobject_uevent_env(struct kobject *kobj, enum kobject_action action, /* allocate message with the maximum possible size */ len = strlen(action_string) + strlen(devpath) + 2; - skb = alloc_skb(len + BUFFER_SIZE, GFP_KERNEL); + skb = alloc_skb(len + env->buflen, GFP_KERNEL); if (skb) { + char *scratch; + /* add header */ scratch = skb_put(skb, len); sprintf(scratch, "%s@%s", action_string, devpath); /* copy keys to our continuous event payload buffer */ - for (i = 2; envp[i]; i++) { - len = strlen(envp[i]) + 1; + for (i = 0; i < env->envp_idx; i++) { + len = strlen(env->envp[i]) + 1; scratch = skb_put(skb, len); - strcpy(scratch, envp[i]); + strcpy(scratch, env->envp[i]); } NETLINK_CB(skb).dst_group = 1; - netlink_broadcast(uevent_sock, skb, 0, 1, GFP_KERNEL); - } + retval = netlink_broadcast(uevent_sock, skb, 0, 1, + GFP_KERNEL); + /* ENOBUFS should be handled in userspace */ + if (retval == -ENOBUFS) + retval = 0; + } else + retval = -ENOMEM; } #endif @@ -197,78 +249,71 @@ void kobject_uevent_env(struct kobject *kobj, enum kobject_action action, argv [0] = uevent_helper; argv [1] = (char *)subsystem; argv [2] = NULL; - call_usermodehelper (argv[0], argv, envp, 0); + retval = add_uevent_var(env, "HOME=/"); + if (retval) + goto exit; + retval = add_uevent_var(env, + "PATH=/sbin:/bin:/usr/sbin:/usr/bin"); + if (retval) + goto exit; + + retval = call_usermodehelper(argv[0], argv, + env->envp, UMH_WAIT_EXEC); } exit: kfree(devpath); - kfree(buffer); - kfree(envp); - return; + kfree(env); + return retval; } - EXPORT_SYMBOL_GPL(kobject_uevent_env); /** * kobject_uevent - notify userspace by ending an uevent * - * @action: action that is happening (usually KOBJ_ADD and KOBJ_REMOVE) + * @action: action that is happening * @kobj: struct kobject that the action is happening to + * + * Returns 0 if kobject_uevent() is completed with success or the + * corresponding error when it fails. */ -void kobject_uevent(struct kobject *kobj, enum kobject_action action) +int kobject_uevent(struct kobject *kobj, enum kobject_action action) { - kobject_uevent_env(kobj, action, NULL); + return kobject_uevent_env(kobj, action, NULL); } - EXPORT_SYMBOL_GPL(kobject_uevent); /** - * add_uevent_var - helper for creating event variables - * @envp: Pointer to table of environment variables, as passed into - * uevent() method. - * @num_envp: Number of environment variable slots available, as - * passed into uevent() method. - * @cur_index: Pointer to current index into @envp. It should be - * initialized to 0 before the first call to add_uevent_var(), - * and will be incremented on success. - * @buffer: Pointer to buffer for environment variables, as passed - * into uevent() method. - * @buffer_size: Length of @buffer, as passed into uevent() method. - * @cur_len: Pointer to current length of space used in @buffer. - * Should be initialized to 0 before the first call to - * add_uevent_var(), and will be incremented on success. - * @format: Format for creating environment variable (of the form - * "XXX=%x") for snprintf(). + * add_uevent_var - add key value string to the environment buffer + * @env: environment buffer structure + * @format: printf format for the key=value pair * * Returns 0 if environment variable was added successfully or -ENOMEM * if no space was available. */ -int add_uevent_var(char **envp, int num_envp, int *cur_index, - char *buffer, int buffer_size, int *cur_len, - const char *format, ...) +int add_uevent_var(struct kobj_uevent_env *env, const char *format, ...) { va_list args; + int len; - /* - * We check against num_envp - 1 to make sure there is at - * least one slot left after we return, since kobject_uevent() - * needs to set the last slot to NULL. - */ - if (*cur_index >= num_envp - 1) + if (env->envp_idx >= ARRAY_SIZE(env->envp)) { + WARN(1, KERN_ERR "add_uevent_var: too many keys\n"); return -ENOMEM; - - envp[*cur_index] = buffer + *cur_len; + } va_start(args, format); - *cur_len += vsnprintf(envp[*cur_index], - max(buffer_size - *cur_len, 0), - format, args) + 1; + len = vsnprintf(&env->buf[env->buflen], + sizeof(env->buf) - env->buflen, + format, args); va_end(args); - if (*cur_len > buffer_size) + if (len >= (sizeof(env->buf) - env->buflen)) { + WARN(1, KERN_ERR "add_uevent_var: buffer size too small\n"); return -ENOMEM; + } - (*cur_index)++; + env->envp[env->envp_idx++] = &env->buf[env->buflen]; + env->buflen += len + 1; return 0; } EXPORT_SYMBOL_GPL(add_uevent_var); @@ -276,19 +321,16 @@ EXPORT_SYMBOL_GPL(add_uevent_var); #if defined(CONFIG_NET) static int __init kobject_uevent_init(void) { - uevent_sock = netlink_kernel_create(NETLINK_KOBJECT_UEVENT, 1, NULL, - THIS_MODULE); - + uevent_sock = netlink_kernel_create(&init_net, NETLINK_KOBJECT_UEVENT, + 1, NULL, NULL, THIS_MODULE); if (!uevent_sock) { printk(KERN_ERR "kobject_uevent: unable to create netlink socket!\n"); return -ENODEV; } - + netlink_set_nonroot(NETLINK_KOBJECT_UEVENT, NL_NONROOT_RECV); return 0; } postcore_initcall(kobject_uevent_init); #endif - -#endif /* CONFIG_HOTPLUG */