From d83f5901bc0cd7131a3b8534169ee889efc4c257 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 30 Jan 2013 19:21:14 -0800 Subject: coda: Restrict coda messages to the initial user namespace Remove the slight chance that uids and gids in coda messages will be interpreted in the wrong user namespace. - Only allow processes in the initial user namespace to open the coda character device to communicate with coda filesystems. - Explicitly convert the uids in the coda header into the initial user namespace. - In coda_vattr_to_attr make kuids and kgids from the initial user namespace uids and gids in struct coda_vattr that just came from userspace. - In coda_iattr_to_vattr convert kuids and kgids into uids and gids in the intial user namespace and store them in struct coda_vattr for sending to coda userspace programs. Nothing needs to be changed with mounts as coda does not support being mounted in anything other than the initial user namespace. Cc: Jan Harkes Signed-off-by: "Eric W. Biederman" diff --git a/fs/coda/coda_linux.c b/fs/coda/coda_linux.c index 854ace7..2849f41 100644 --- a/fs/coda/coda_linux.c +++ b/fs/coda/coda_linux.c @@ -100,9 +100,9 @@ void coda_vattr_to_iattr(struct inode *inode, struct coda_vattr *attr) if (attr->va_mode != (u_short) -1) inode->i_mode = attr->va_mode | inode_type; if (attr->va_uid != -1) - inode->i_uid = (uid_t) attr->va_uid; + inode->i_uid = make_kuid(&init_user_ns, (uid_t) attr->va_uid); if (attr->va_gid != -1) - inode->i_gid = (gid_t) attr->va_gid; + inode->i_gid = make_kgid(&init_user_ns, (gid_t) attr->va_gid); if (attr->va_nlink != -1) set_nlink(inode, attr->va_nlink); if (attr->va_size != -1) @@ -171,10 +171,10 @@ void coda_iattr_to_vattr(struct iattr *iattr, struct coda_vattr *vattr) vattr->va_mode = iattr->ia_mode; } if ( valid & ATTR_UID ) { - vattr->va_uid = (vuid_t) iattr->ia_uid; + vattr->va_uid = (vuid_t) from_kuid(&init_user_ns, iattr->ia_uid); } if ( valid & ATTR_GID ) { - vattr->va_gid = (vgid_t) iattr->ia_gid; + vattr->va_gid = (vgid_t) from_kgid(&init_user_ns, iattr->ia_gid); } if ( valid & ATTR_SIZE ) { vattr->va_size = iattr->ia_size; diff --git a/fs/coda/psdev.c b/fs/coda/psdev.c index dd60f90..ebc2bae 100644 --- a/fs/coda/psdev.c +++ b/fs/coda/psdev.c @@ -270,6 +270,9 @@ static int coda_psdev_open(struct inode * inode, struct file * file) if (task_active_pid_ns(current) != &init_pid_ns) return -EINVAL; + if (current_user_ns() != &init_user_ns) + return -EINVAL; + idx = iminor(inode); if (idx < 0 || idx >= MAX_CODADEVS) return -ENODEV; diff --git a/fs/coda/upcall.c b/fs/coda/upcall.c index 5c6d2cd..3a73197 100644 --- a/fs/coda/upcall.c +++ b/fs/coda/upcall.c @@ -52,7 +52,7 @@ static void *alloc_upcall(int opcode, int size) inp->ih.opcode = opcode; inp->ih.pid = task_pid_nr_ns(current, &init_pid_ns); inp->ih.pgid = task_pgrp_nr_ns(current, &init_pid_ns); - inp->ih.uid = current_fsuid(); + inp->ih.uid = from_kuid(&init_user_ns, current_fsuid()); return (void*)inp; } @@ -157,7 +157,7 @@ int venus_lookup(struct super_block *sb, struct CodaFid *fid, } int venus_close(struct super_block *sb, struct CodaFid *fid, int flags, - vuid_t uid) + kuid_t uid) { union inputArgs *inp; union outputArgs *outp; @@ -166,7 +166,7 @@ int venus_close(struct super_block *sb, struct CodaFid *fid, int flags, insize = SIZE(release); UPARG(CODA_CLOSE); - inp->ih.uid = uid; + inp->ih.uid = from_kuid(&init_user_ns, uid); inp->coda_close.VFid = *fid; inp->coda_close.flags = flags; diff --git a/include/linux/coda_psdev.h b/include/linux/coda_psdev.h index 8031d6e..5b8721e 100644 --- a/include/linux/coda_psdev.h +++ b/include/linux/coda_psdev.h @@ -34,7 +34,7 @@ int venus_lookup(struct super_block *sb, struct CodaFid *fid, const char *name, int length, int *type, struct CodaFid *resfid); int venus_close(struct super_block *sb, struct CodaFid *fid, int flags, - vuid_t uid); + kuid_t uid); int venus_open(struct super_block *sb, struct CodaFid *fid, int flags, struct file **f); int venus_mkdir(struct super_block *sb, struct CodaFid *dirfid, -- cgit v0.10.2