| 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
| ||
|
Message-Id: <20080519123110.930491B41FF@basil.firstfloor.org>
Date: Mon, 19 May 2008 14:31:10 +0200 (CEST)
From: Andi Kleen <andi@...stfloor.org>
To: Trond.Myklebust@...app.com, swhiteho@...hat.com, sfrench@...ba.org,
vandrove@...cvut.cz, corbet@....net, linux-kernel@...r.kernel.org
Subject: [PATCH] [1/11] Remove BKL from remote_llseek
- Replace remote_llseek with remote_llseek_unlocked (to force compilation
failures in all users)
- Change all users to either use remote_llseek directly or take the
BKL around. I changed the file systems who don't use the BKL
for anything (CIFS, GFS) to call it directly. NCPFS and SMBFS and NFS
take the BKL, but explicitely in their own source now.
I moved them all over in a single patch to avoid unbisectable sections.
Open problem: 32bit kernels can corrupt fpos because its modification
is not atomic, but they can do that anyways because there's other paths who
modify it without BKL.
Cc: Trond.Myklebust@...app.com
Cc: swhiteho@...hat.com
Cc: sfrench@...ba.org
Cc: vandrove@...cvut.cz
Signed-off-by: Andi Kleen <ak@...e.de>
Signed-off-by: Andi Kleen <ak@...ux.intel.com>
---
fs/cifs/cifsfs.c | 2 +-
fs/gfs2/ops_file.c | 4 ++--
fs/ncpfs/file.c | 12 +++++++++++-
fs/nfs/file.c | 6 +++++-
fs/read_write.c | 7 +++----
fs/smbfs/file.c | 11 ++++++++++-
include/linux/fs.h | 3 ++-
7 files changed, 34 insertions(+), 11 deletions(-)
Index: linux/fs/cifs/cifsfs.c
===================================================================
--- linux.orig/fs/cifs/cifsfs.c
+++ linux/fs/cifs/cifsfs.c
@@ -581,7 +581,7 @@ static loff_t cifs_llseek(struct file *f
if (retval < 0)
return (loff_t)retval;
}
- return remote_llseek(file, offset, origin);
+ return remote_llseek_unlocked(file, offset, origin);
}
struct file_system_type cifs_fs_type = {
Index: linux/fs/gfs2/ops_file.c
===================================================================
--- linux.orig/fs/gfs2/ops_file.c
+++ linux/fs/gfs2/ops_file.c
@@ -62,11 +62,11 @@ static loff_t gfs2_llseek(struct file *f
error = gfs2_glock_nq_init(ip->i_gl, LM_ST_SHARED, LM_FLAG_ANY,
&i_gh);
if (!error) {
- error = remote_llseek(file, offset, origin);
+ error = remote_llseek_unlocked(file, offset, origin);
gfs2_glock_dq_uninit(&i_gh);
}
} else
- error = remote_llseek(file, offset, origin);
+ error = remote_llseek_unlocked(file, offset, origin);
return error;
}
Index: linux/fs/ncpfs/file.c
===================================================================
--- linux.orig/fs/ncpfs/file.c
+++ linux/fs/ncpfs/file.c
@@ -18,6 +18,7 @@
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/sched.h>
+#include <linux/smp_lock.h>
#include <linux/ncp_fs.h>
#include "ncplib_kernel.h"
@@ -281,9 +282,18 @@ static int ncp_release(struct inode *ino
return 0;
}
+static loff_t ncp_remote_llseek(struct file *file, loff_t offset, int origin)
+{
+ loff_t ret;
+ lock_kernel();
+ ret = remote_llseek_unlocked(file, offset, origin);
+ unlock_kernel();
+ return ret;
+}
+
const struct file_operations ncp_file_operations =
{
- .llseek = remote_llseek,
+ .llseek = ncp_remote_llseek,
.read = ncp_file_read,
.write = ncp_file_write,
.ioctl = ncp_ioctl,
Index: linux/fs/read_write.c
===================================================================
--- linux.orig/fs/read_write.c
+++ linux/fs/read_write.c
@@ -58,11 +58,10 @@ loff_t generic_file_llseek(struct file *
EXPORT_SYMBOL(generic_file_llseek);
-loff_t remote_llseek(struct file *file, loff_t offset, int origin)
+loff_t remote_llseek_unlocked(struct file *file, loff_t offset, int origin)
{
loff_t retval;
- lock_kernel();
switch (origin) {
case SEEK_END:
offset += i_size_read(file->f_path.dentry->d_inode);
@@ -73,15 +72,15 @@ loff_t remote_llseek(struct file *file,
retval = -EINVAL;
if (offset>=0 && offset<=file->f_path.dentry->d_inode->i_sb->s_maxbytes) {
if (offset != file->f_pos) {
+ /* AK: do we need a lock for those? */
file->f_pos = offset;
file->f_version = 0;
}
retval = offset;
}
- unlock_kernel();
return retval;
}
-EXPORT_SYMBOL(remote_llseek);
+EXPORT_SYMBOL(remote_llseek_unlocked);
loff_t no_llseek(struct file *file, loff_t offset, int origin)
{
Index: linux/fs/smbfs/file.c
===================================================================
--- linux.orig/fs/smbfs/file.c
+++ linux/fs/smbfs/file.c
@@ -422,9 +422,18 @@ smb_file_permission(struct inode *inode,
return error;
}
+static loff_t smb_remote_llseek(struct file *file, loff_t offset, int origin)
+{
+ loff_t ret;
+ lock_kernel();
+ ret = remote_llseek_unlocked(file, offset, origin);
+ unlock_kernel();
+ return ret;
+}
+
const struct file_operations smb_file_operations =
{
- .llseek = remote_llseek,
+ .llseek = smb_remote_llseek,
.read = do_sync_read,
.aio_read = smb_file_aio_read,
.write = do_sync_write,
Index: linux/include/linux/fs.h
===================================================================
--- linux.orig/include/linux/fs.h
+++ linux/include/linux/fs.h
@@ -1871,7 +1871,8 @@ extern void
file_ra_state_init(struct file_ra_state *ra, struct address_space *mapping);
extern loff_t no_llseek(struct file *file, loff_t offset, int origin);
extern loff_t generic_file_llseek(struct file *file, loff_t offset, int origin);
-extern loff_t remote_llseek(struct file *file, loff_t offset, int origin);
+extern loff_t remote_llseek_unlocked(struct file *file, loff_t offset,
+ int origin);
extern int generic_file_open(struct inode * inode, struct file * filp);
extern int nonseekable_open(struct inode * inode, struct file * filp);
Index: linux/fs/nfs/file.c
===================================================================
--- linux.orig/fs/nfs/file.c
+++ linux/fs/nfs/file.c
@@ -170,6 +170,7 @@ force_reval:
static loff_t nfs_file_llseek(struct file *filp, loff_t offset, int origin)
{
+ loff_t loff;
/* origin == SEEK_END => we must revalidate the cached file length */
if (origin == SEEK_END) {
struct inode *inode = filp->f_mapping->host;
@@ -177,7 +178,10 @@ static loff_t nfs_file_llseek(struct fil
if (retval < 0)
return (loff_t)retval;
}
- return remote_llseek(filp, offset, origin);
+ lock_kernel(); /* BKL needed? */
+ loff = remote_llseek_unlocked(filp, offset, origin);
+ unlock_kernel();
+ return loff;
}
/*
--
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