diff options
Diffstat (limited to 'fs/signalfd.c')
| -rw-r--r-- | fs/signalfd.c | 172 |
1 files changed, 131 insertions, 41 deletions
diff --git a/fs/signalfd.c b/fs/signalfd.c index aefb0be0794..424b7b65321 100644 --- a/fs/signalfd.c +++ b/fs/signalfd.c @@ -22,11 +22,30 @@ #include <linux/init.h> #include <linux/fs.h> #include <linux/sched.h> +#include <linux/slab.h> #include <linux/kernel.h> #include <linux/signal.h> #include <linux/list.h> #include <linux/anon_inodes.h> #include <linux/signalfd.h> +#include <linux/syscalls.h> +#include <linux/proc_fs.h> +#include <linux/compat.h> + +void signalfd_cleanup(struct sighand_struct *sighand) +{ + wait_queue_head_t *wqh = &sighand->signalfd_wqh; + /* + * The lockless check can race with remove_wait_queue() in progress, + * but in this case its caller should run under rcu_read_lock() and + * sighand_cachep is SLAB_DESTROY_BY_RCU, we can safely return. + */ + if (likely(!waitqueue_active(wqh))) + return; + + /* wait_queue_t->func(POLLFREE) should do remove_wait_queue() */ + wake_up_poll(wqh, POLLHUP | POLLFREE); +} struct signalfd_ctx { sigset_t sigmask; @@ -66,7 +85,7 @@ static int signalfd_copyinfo(struct signalfd_siginfo __user *uinfo, BUILD_BUG_ON(sizeof(struct signalfd_siginfo) != 128); /* - * Unused memebers should be zero ... + * Unused members should be zero ... */ err = __clear_user(uinfo, sizeof(*uinfo)); @@ -74,45 +93,62 @@ static int signalfd_copyinfo(struct signalfd_siginfo __user *uinfo, * If you change siginfo_t structure, please be sure * this code is fixed accordingly. */ - err |= __put_user(kinfo->si_signo, &uinfo->signo); - err |= __put_user(kinfo->si_errno, &uinfo->err); - err |= __put_user((short)kinfo->si_code, &uinfo->code); + err |= __put_user(kinfo->si_signo, &uinfo->ssi_signo); + err |= __put_user(kinfo->si_errno, &uinfo->ssi_errno); + err |= __put_user((short) kinfo->si_code, &uinfo->ssi_code); switch (kinfo->si_code & __SI_MASK) { case __SI_KILL: - err |= __put_user(kinfo->si_pid, &uinfo->pid); - err |= __put_user(kinfo->si_uid, &uinfo->uid); + err |= __put_user(kinfo->si_pid, &uinfo->ssi_pid); + err |= __put_user(kinfo->si_uid, &uinfo->ssi_uid); break; case __SI_TIMER: - err |= __put_user(kinfo->si_tid, &uinfo->tid); - err |= __put_user(kinfo->si_overrun, &uinfo->overrun); - err |= __put_user((long)kinfo->si_ptr, &uinfo->svptr); + err |= __put_user(kinfo->si_tid, &uinfo->ssi_tid); + err |= __put_user(kinfo->si_overrun, &uinfo->ssi_overrun); + err |= __put_user((long) kinfo->si_ptr, &uinfo->ssi_ptr); + err |= __put_user(kinfo->si_int, &uinfo->ssi_int); break; case __SI_POLL: - err |= __put_user(kinfo->si_band, &uinfo->band); - err |= __put_user(kinfo->si_fd, &uinfo->fd); + err |= __put_user(kinfo->si_band, &uinfo->ssi_band); + err |= __put_user(kinfo->si_fd, &uinfo->ssi_fd); break; case __SI_FAULT: - err |= __put_user((long)kinfo->si_addr, &uinfo->addr); + err |= __put_user((long) kinfo->si_addr, &uinfo->ssi_addr); #ifdef __ARCH_SI_TRAPNO - err |= __put_user(kinfo->si_trapno, &uinfo->trapno); + err |= __put_user(kinfo->si_trapno, &uinfo->ssi_trapno); +#endif +#ifdef BUS_MCEERR_AO + /* + * Other callers might not initialize the si_lsb field, + * so check explicitly for the right codes here. + */ + if (kinfo->si_code == BUS_MCEERR_AR || + kinfo->si_code == BUS_MCEERR_AO) + err |= __put_user((short) kinfo->si_addr_lsb, + &uinfo->ssi_addr_lsb); #endif break; case __SI_CHLD: - err |= __put_user(kinfo->si_pid, &uinfo->pid); - err |= __put_user(kinfo->si_uid, &uinfo->uid); - err |= __put_user(kinfo->si_status, &uinfo->status); - err |= __put_user(kinfo->si_utime, &uinfo->utime); - err |= __put_user(kinfo->si_stime, &uinfo->stime); + err |= __put_user(kinfo->si_pid, &uinfo->ssi_pid); + err |= __put_user(kinfo->si_uid, &uinfo->ssi_uid); + err |= __put_user(kinfo->si_status, &uinfo->ssi_status); + err |= __put_user(kinfo->si_utime, &uinfo->ssi_utime); + err |= __put_user(kinfo->si_stime, &uinfo->ssi_stime); break; case __SI_RT: /* This is not generated by the kernel as of now. */ case __SI_MESGQ: /* But this is */ - err |= __put_user(kinfo->si_pid, &uinfo->pid); - err |= __put_user(kinfo->si_uid, &uinfo->uid); - err |= __put_user((long)kinfo->si_ptr, &uinfo->svptr); + err |= __put_user(kinfo->si_pid, &uinfo->ssi_pid); + err |= __put_user(kinfo->si_uid, &uinfo->ssi_uid); + err |= __put_user((long) kinfo->si_ptr, &uinfo->ssi_ptr); + err |= __put_user(kinfo->si_int, &uinfo->ssi_int); break; - default: /* this is just in case for now ... */ - err |= __put_user(kinfo->si_pid, &uinfo->pid); - err |= __put_user(kinfo->si_uid, &uinfo->uid); + default: + /* + * This case catches also the signals queued by sigqueue(). + */ + err |= __put_user(kinfo->si_pid, &uinfo->ssi_pid); + err |= __put_user(kinfo->si_uid, &uinfo->ssi_uid); + err |= __put_user((long) kinfo->si_ptr, &uinfo->ssi_ptr); + err |= __put_user(kinfo->si_int, &uinfo->ssi_int); break; } @@ -193,19 +229,42 @@ static ssize_t signalfd_read(struct file *file, char __user *buf, size_t count, return total ? total: ret; } +#ifdef CONFIG_PROC_FS +static int signalfd_show_fdinfo(struct seq_file *m, struct file *f) +{ + struct signalfd_ctx *ctx = f->private_data; + sigset_t sigmask; + + sigmask = ctx->sigmask; + signotset(&sigmask); + render_sigset_t(m, "sigmask:\t", &sigmask); + + return 0; +} +#endif + static const struct file_operations signalfd_fops = { +#ifdef CONFIG_PROC_FS + .show_fdinfo = signalfd_show_fdinfo, +#endif .release = signalfd_release, .poll = signalfd_poll, .read = signalfd_read, + .llseek = noop_llseek, }; -asmlinkage long sys_signalfd(int ufd, sigset_t __user *user_mask, size_t sizemask) +SYSCALL_DEFINE4(signalfd4, int, ufd, sigset_t __user *, user_mask, + size_t, sizemask, int, flags) { - int error; sigset_t sigmask; struct signalfd_ctx *ctx; - struct file *file; - struct inode *inode; + + /* Check the SFD_* constants for consistency. */ + BUILD_BUG_ON(SFD_CLOEXEC != O_CLOEXEC); + BUILD_BUG_ON(SFD_NONBLOCK != O_NONBLOCK); + + if (flags & ~(SFD_CLOEXEC | SFD_NONBLOCK)) + return -EINVAL; if (sizemask != sizeof(sigset_t) || copy_from_user(&sigmask, user_mask, sizeof(sigmask))) @@ -224,17 +283,17 @@ asmlinkage long sys_signalfd(int ufd, sigset_t __user *user_mask, size_t sizemas * When we call this, the initialization must be complete, since * anon_inode_getfd() will install the fd. */ - error = anon_inode_getfd(&ufd, &inode, &file, "[signalfd]", - &signalfd_fops, ctx); - if (error) - goto err_fdalloc; + ufd = anon_inode_getfd("[signalfd]", &signalfd_fops, ctx, + O_RDWR | (flags & (O_CLOEXEC | O_NONBLOCK))); + if (ufd < 0) + kfree(ctx); } else { - file = fget(ufd); - if (!file) + struct fd f = fdget(ufd); + if (!f.file) return -EBADF; - ctx = file->private_data; - if (file->f_op != &signalfd_fops) { - fput(file); + ctx = f.file->private_data; + if (f.file->f_op != &signalfd_fops) { + fdput(f); return -EINVAL; } spin_lock_irq(¤t->sighand->siglock); @@ -242,13 +301,44 @@ asmlinkage long sys_signalfd(int ufd, sigset_t __user *user_mask, size_t sizemas spin_unlock_irq(¤t->sighand->siglock); wake_up(¤t->sighand->signalfd_wqh); - fput(file); + fdput(f); } return ufd; +} -err_fdalloc: - kfree(ctx); - return error; +SYSCALL_DEFINE3(signalfd, int, ufd, sigset_t __user *, user_mask, + size_t, sizemask) +{ + return sys_signalfd4(ufd, user_mask, sizemask, 0); } +#ifdef CONFIG_COMPAT +COMPAT_SYSCALL_DEFINE4(signalfd4, int, ufd, + const compat_sigset_t __user *,sigmask, + compat_size_t, sigsetsize, + int, flags) +{ + compat_sigset_t ss32; + sigset_t tmp; + sigset_t __user *ksigmask; + + if (sigsetsize != sizeof(compat_sigset_t)) + return -EINVAL; + if (copy_from_user(&ss32, sigmask, sizeof(ss32))) + return -EFAULT; + sigset_from_compat(&tmp, &ss32); + ksigmask = compat_alloc_user_space(sizeof(sigset_t)); + if (copy_to_user(ksigmask, &tmp, sizeof(sigset_t))) + return -EFAULT; + + return sys_signalfd4(ufd, ksigmask, sizeof(sigset_t), flags); +} + +COMPAT_SYSCALL_DEFINE3(signalfd, int, ufd, + const compat_sigset_t __user *,sigmask, + compat_size_t, sigsetsize) +{ + return compat_sys_signalfd4(ufd, sigmask, sigsetsize, 0); +} +#endif |