Page MenuHomeFreeBSD
Differential D25559 Diff 74099 sys/compat/linux/linux_stats.c

Changeset View

Standalone View

View Options

sys/compat/linux/linux_stats.c

Show First 20 Lines • Show All 118 Lines • ▼ Show 20 Lines if ((!S_ISCHR(buf->st_mode) && !S_ISBLK(buf->st_mode)) ||
fget(td, fd, &cap_no_rights, &fp) != 0) fget(td, fd, &cap_no_rights, &fp) != 0)
return; return;
vp = fp->f_vnode; vp = fp->f_vnode;
if (vp != NULL && vn_isdisk(vp, NULL)) { if (vp != NULL && vn_isdisk(vp, NULL)) {
buf->st_mode &= ~S_IFMT; buf->st_mode &= ~S_IFMT;
buf->st_mode |= S_IFBLK; buf->st_mode |= S_IFBLK;
} }
if (vp != NULL && vp->v_rdev != NULL && if (vp != NULL && vp->v_rdev != NULL &&
linux_driver_get_major_minor(devtoname(vp->v_rdev), linux_driver_get_major_minor(devtoname(vp->v_rdev),
kibUnsubmitted
Not Done
Inline Actions

I think you should add __compiler_barrier() after this line, so that compiler is not allowed to reload v_mount later.

kib: I think you should add __compiler_barrier() after this line, so that compiler is not allowed to…
kibUnsubmitted
Not Done
Inline Actions

(unrelated) This is very buggy. First, v_rdev is a member of union, it only means something for char vnodes. Second, it is unsafe, r_dev can be invalidated any time.

kib: (unrelated) This is very buggy. First, v_rdev is a member of union, it only means something…
traszAuthorUnsubmitted
Done
Inline Actions

I wonder if I should just vn_lock() before doing all this?

trasz: I wonder if I should just vn_lock() before doing all this?
kibUnsubmitted
Not Done
Inline Actions

vnode lock might be not enough to ensure stability of *v_rdev

Look at vn_isdisk() to how to access v_rdev safely.

kib: vnode lock might be not enough to ensure stability of *v_rdev Look at vn_isdisk() to how to…
&major, &minor) == 0) { &major, &minor) == 0) {
buf->st_rdev = (major << 8 | minor); buf->st_rdev = (major << 8 | minor);
} else if (fp->f_type == DTYPE_PTS) { } else if (fp->f_type == DTYPE_PTS) {
struct tty *tp = fp->f_data; struct tty *tp = fp->f_data;
/* Convert the numbers for the slave device. */ /* Convert the numbers for the slave device. */
if (linux_driver_get_major_minor(devtoname(tp->t_dev), if (linux_driver_get_major_minor(devtoname(tp->t_dev),
&major, &minor) == 0) { &major, &minor) == 0) {
Show All 24 Lines
static int static int
newstat_copyout(struct stat *buf, void *ubuf) newstat_copyout(struct stat *buf, void *ubuf)
{ {
struct l_newstat tbuf; struct l_newstat tbuf;
bzero(&tbuf, sizeof(tbuf)); bzero(&tbuf, sizeof(tbuf));
tbuf.st_dev = dev_to_ldev(buf->st_dev); tbuf.st_dev = dev_to_ldev(buf->st_dev);
/*
* Return the same st_dev for every devfs instance. The reason
* for this is to work around an idiosyncrasy of glibc getttynam()
* implementation: it checks whether st_dev returned for fd 0
* is the same as st_dev returned for the target of /proc/self/fd/0
* symlink, and with linux chroots having their own devfs instance,
* the check will fail if you chroot into it.
*/
if ((S_ISCHR(buf->st_mode) || S_ISBLK(buf->st_mode)) &&
rootdevmp != NULL) {
tbuf.st_dev = dev_to_ldev(rootdevmp->mnt_stat.f_fsid.val[0]);
}
tbuf.st_ino = buf->st_ino; tbuf.st_ino = buf->st_ino;
tbuf.st_mode = buf->st_mode; tbuf.st_mode = buf->st_mode;
tbuf.st_nlink = buf->st_nlink; tbuf.st_nlink = buf->st_nlink;
tbuf.st_uid = buf->st_uid; tbuf.st_uid = buf->st_uid;
tbuf.st_gid = buf->st_gid; tbuf.st_gid = buf->st_gid;
tbuf.st_rdev = buf->st_rdev; tbuf.st_rdev = buf->st_rdev;
tbuf.st_size = buf->st_size; tbuf.st_size = buf->st_size;
tbuf.st_atim.tv_sec = buf->st_atim.tv_sec; tbuf.st_atim.tv_sec = buf->st_atim.tv_sec;
▲ Show 20 Lines • Show All 504 Lines • Show Last 20 Lines