Isn't here a race?
linux-2.4.20-vanilla/fs/namespace.c:chroot_fs_refs():
[called from sys_pivot_root():
# read_lock(&tasklist_lock);
# for_each_task(p) {
# task_lock(p);
# fs = p->fs;
# if (fs) {
# atomic_inc(&fs->count);
# task_unlock(p);
# if (fs->root==old_nd->dentry&&fs->rootmnt==old_nd->mnt)
# set_fs_root(fs, new_nd->mnt, new_nd->dentry);
While include/linux/fs_struct.h:set_fs_root():
[called from sys_chroot()]
# write_lock(&fs->lock);
# old_root = fs->root;
# old_rootmnt = fs->rootmnt;
# fs->rootmnt = mntget(mnt);
# fs->root = dget(dentry);
Shouldn't chroot_fs_refs() read_lock() fs->lock? What if p is in
the middle of a chroot() on another CPU while we trying to pivot_root()?
bit,
adam
--
1024D/37B8D989 954B 998A E5F5 BA2A 3622 82DD 54C2 843D 37B8 D989
finger://borso@vekoll.vein.hu | Some days, my soul's confined
http://www.keyserver.net | And out of mind
Sleep forever
--
Kernelnewbies: Help each other learn about the Linux kernel.
Archive: http://mail.nl.linux.org/kernelnewbies/
FAQ: http://kernelnewbies.org/faq/
