d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Do not dereference vp->v_rdev without holding any of dev_mtx or vnode

Browse Source 
lock. Use code similar to devfs_fp_check(), but inlined to feet other
checks performed by ttyhook_register().

Reviewed by:	ed
This commit is contained in:
Konstantin Belousov 2009-06-08 13:34:45 +00:00
parent 22ebfa45f0
commit ce3fa4d5cf
1 changed files with 20 additions and 8 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

28
sys/kern/tty.c
View File

@ -1742,19 +1742,31 @@ ttyhook_register(struct tty **rtp, struct proc *p, int fd,
goto done1;
}
/* Make sure the vnode is bound to a character device. */
error = EINVAL;
if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VCHR ||
fp->f_vnode->v_rdev == NULL)
/*
* Make sure the vnode is bound to a character device.
* Unlocked check for the vnode type is ok there, because we
* only shall prevent calling devvn_refthread on the file that
* never has been opened over a character device.
*/
if (fp->f_type != DTYPE_VNODE || fp->f_vnode->v_type != VCHR) {
error = EINVAL;
goto done1;
dev = fp->f_vnode->v_rdev;
}
/* Make sure it is a TTY. */
cdp = dev_refthread(dev);
if (cdp == NULL)
cdp = devvn_refthread(fp->f_vnode, &dev);
if (cdp == NULL) {
error = ENXIO;
goto done1;
if (cdp != &ttydev_cdevsw)
}
if (dev != fp->f_data) {
error = ENXIO;
goto done2;
}
if (cdp != &ttydev_cdevsw) {
error = ENOTTY;
goto done2;
}
tp = dev->si_drv1;
/* Try to attach the hook to the TTY. */