(Adrian should be CCed on things regarding 2.6.16.y kernel) On Sun, 23 Sep 2007, Miloslav Semler wrote:
> This patch solves CVE-2007-3104 - sysfs_readdir oops. > More can be found here: > http://git.kernel.org/?p=linux/kernel/git/stable/linux-2.6.22.y.git;a=commit;h=dc351252b33f8fede396d6173dba117bcb933607 > > Signed-off-by: Miloslav Semler > --- > diff -uprN linux-2.6.16.53/fs/sysfs/dir.c linux-2.6.16.53-new/fs/sysfs/dir.c > --- linux-2.6.16.53/fs/sysfs/dir.c 2007-07-25 23:05:45.000000000 +0200 > +++ linux-2.6.16.53-new/fs/sysfs/dir.c 2007-09-23 18:18:09.000000000 +0200 > @@ -29,6 +29,14 @@ static struct dentry_operations sysfs_de > .d_iput = sysfs_d_iput, > }; > > +static unsigned int sysfs_inode_counter; > +ino_t sysfs_get_inum(void) > +{ > + if (unlikely(sysfs_inode_counter < 3)) > + sysfs_inode_counter = 3; > + return sysfs_inode_counter++; > +} > + > /* > * Allocates a new sysfs_dirent and links it to the parent sysfs_dirent > */ > @@ -40,8 +48,10 @@ static struct sysfs_dirent * sysfs_new_d > sd = kmem_cache_alloc(sysfs_dir_cachep, GFP_KERNEL); > if (!sd) > return NULL; > + > > memset(sd, 0, sizeof(*sd)); > + sd->s_ino = sysfs_get_inum(); > atomic_set(&sd->s_count, 1); > INIT_LIST_HEAD(&sd->s_children); > list_add(&sd->s_sibling, &parent_sd->s_children); > @@ -385,7 +395,7 @@ static int sysfs_readdir(struct file * f > > switch (i) { > case 0: > - ino = dentry->d_inode->i_ino; > + ino = parent_sd->s_ino; > if (filldir(dirent, ".", 1, i, ino, DT_DIR) < 0) > break; > filp->f_pos++; > @@ -415,10 +425,7 @@ static int sysfs_readdir(struct file * f > > name = sysfs_get_name(next); > len = strlen(name); > - if (next->s_dentry) > - ino = next->s_dentry->d_inode->i_ino; > - else > - ino = iunique(sysfs_sb, 2); > + ino = next->s_ino; > > if (filldir(dirent, name, len, filp->f_pos, > ino, > dt_type(next)) < 0) > diff -uprN linux-2.6.16.53/fs/sysfs/inode.c > linux-2.6.16.53-new/fs/sysfs/inode.c > --- linux-2.6.16.53/fs/sysfs/inode.c 2007-07-25 23:05:45.000000000 +0200 > +++ linux-2.6.16.53-new/fs/sysfs/inode.c 2007-09-23 18:18:09.000000000 > +0200 > @@ -119,6 +119,7 @@ struct inode * sysfs_new_inode(mode_t mo > inode->i_mapping->a_ops = &sysfs_aops; > inode->i_mapping->backing_dev_info = > &sysfs_backing_dev_info; > inode->i_op = &sysfs_inode_operations; > + inode->i_ino = sd->s_ino; > > if (sd->s_iattr) { > /* sysfs_dirent has non-default attributes > diff -uprN linux-2.6.16.53/fs/sysfs/mount.c > linux-2.6.16.53-new/fs/sysfs/mount.c > --- linux-2.6.16.53/fs/sysfs/mount.c 2007-07-25 23:05:45.000000000 +0200 > +++ linux-2.6.16.53-new/fs/sysfs/mount.c 2007-09-23 18:18:09.000000000 > +0200 > @@ -29,6 +29,7 @@ static struct sysfs_dirent sysfs_root = > .s_element = NULL, > .s_type = SYSFS_ROOT, > .s_iattr = NULL, > + .s_ino = 1, > }; > > static int sysfs_fill_super(struct super_block *sb, void *data, int silent) > diff -uprN linux-2.6.16.53/include/linux/sysfs.h > linux-2.6.16.53-new/include/linux/sysfs.h > --- linux-2.6.16.53/include/linux/sysfs.h 2007-07-25 23:05:45.000000000 > +0200 > +++ linux-2.6.16.53-new/include/linux/sysfs.h 2007-09-23 18:18:09.000000000 > +0200 > @@ -72,6 +72,7 @@ struct sysfs_dirent { > void * s_element; > int s_type; > umode_t s_mode; > + ino_t s_ino; > struct dentry * s_dentry; > struct iattr * s_iattr; > }; > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to [EMAIL PROTECTED] > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > > - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
