| 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: Sat, 4 Jun 2011 00:11:58 +0100 From: Al Viro <viro@...IV.linux.org.uk> To: Dmitry Dmitriev <dimondmm@...dex.ru> Cc: linux-fsdevel@...r.kernel.org, linux-kernel@...r.kernel.org Subject: Re: PROBLEM: Corrupting d_count of target dentry, when rename directory to the directory which is mount point, or when rename directory which is mount point to the existing directory. > When new_dentry exist, i.e. 'target' is not NULL, and a mount point( or old dentry is a mount point ), then function set 'error' variable to -EBUSY( line 2581 ). After that function will call dput function for new_dentry( line 2595 ) without corresponding dget. In this case d_count of dentry become corrupted. In case when old dentry and new dentry are not mount points, dget for new dentry is called in dentry_unhash function. What do you mean, without corresponding dget()? It's done in dentry_unhash(). Oh, hell... We don't call it in that case. Right. vfs_rmdir() used to do dentry_unhash() before the checks for mountpoints, vfs_rename_other() - only after. The funny part is, it got accidentally fixed in this merge window. -stable still needs fixing - by moving dentry_unhash() down past the checks for d_mountpoint(). Mainline should be OK now... -- 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