lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
Open Source and information security mailing list archives
| ||
|
Date: Tue, 02 Dec 2008 01:15:08 +0100 From: Andi Kleen <ak@...ux.intel.com> To: Oleg Nesterov <oleg@...hat.com> CC: Jonathan Corbet <corbet@....net>, Al Viro <viro@...iv.linux.org.uk>, Vitaly Mayatskikh <vmayatsk@...hat.com>, linux-kernel@...r.kernel.org Subject: Re: BUG? "Call fasync() functions without the BKL" is racy > Perhaps, we can add O_LOCK_FLAGS, then something like > > --- a/fs/fcntl.c > +++ b/fs/fcntl.c > @@ -175,6 +175,15 @@ static int setfl(int fd, struct file * f > if (error) > return error; > > + spin_lock(¤t->files->file_lock); > + if (!(filp->f_flags & O_LOCK_FLAGS)) > + filp->f_flags |= O_LOCK_FLAGS; > + else > + error = -EAGAIN; > + spin_unlock(¤t->files->file_lock); > + if (error) /* pretend ->f_flags was changed after us */ > + return 0; > + > if ((arg ^ filp->f_flags) & FASYNC) { > if (filp->f_op && filp->f_op->fasync) { > error = filp->f_op->fasync(fd, filp, (arg & FASYNC) != 0); > @@ -183,7 +192,8 @@ static int setfl(int fd, struct file * f > } > } > > - filp->f_flags = (arg & SETFL_MASK) | (filp->f_flags & ~SETFL_MASK); > + filp->f_flags = (arg & SETFL_MASK) | > + (filp->f_flags & ~(SETFL_MASK | O_LOCK_FLAGS)); > out: > return error; > } > > What do you think? Looks reasonable. Just would need to make sure that O_LOCK_FLAGS doesn't leak out to user space. -Andi > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@...r.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists