diff options
| author | Marcel Holtmann <marcel@holtmann.org> | 2006-11-08 08:10:30 +0100 |
|---|---|---|
| committer | Adrian Bunk <bunk@stusta.de> | 2006-11-08 08:10:30 +0100 |
| commit | 5db60db61aaa613f8c6dffa4213797c0dd83a8fd (patch) | |
| tree | 414ed9d3e118beff48f193da72c2b30adbc11145 | |
| parent | 5f4b6b038a617c333fd4c3b6d66ca31c51dddd5f (diff) | |
Don't allow chmod() on the /proc/<pid>/ files
This just turns off chmod() on the /proc/<pid>/ files, since there is no
good reason to allow it, and had we disallowed it originally, the nasty
/proc race exploit wouldn't have been possible.
The other patches already fixed the problem chmod() could cause, so this
is really just some final mop-up..
This particular version is based off a patch by Eugene and Marcel which
had much better naming than my original equivalent one.
Signed-off-by: Eugene Teo <eteo@redhat.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
| -rw-r--r-- | fs/proc/base.c | 33 |
1 files changed, 32 insertions, 1 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index 38f39c18349..155602fa431 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -590,6 +590,27 @@ static int proc_permission(struct inode *inode, int mask, struct nameidata *nd) return proc_check_root(inode); } +static int proc_setattr(struct dentry *dentry, struct iattr *attr) +{ + int error; + struct inode *inode = dentry->d_inode; + + if (attr->ia_valid & ATTR_MODE) + return -EPERM; + + error = inode_change_ok(inode, attr); + if (!error) { + error = security_inode_setattr(dentry, attr); + if (!error) + error = inode_setattr(inode, attr); + } + return error; +} + +static struct inode_operations proc_def_inode_operations = { + .setattr = proc_setattr, +}; + static int proc_task_permission(struct inode *inode, int mask, struct nameidata *nd) { struct dentry *root; @@ -949,6 +970,7 @@ static struct file_operations proc_oom_adjust_operations = { static struct inode_operations proc_mem_inode_operations = { .permission = proc_permission, + .setattr = proc_setattr, }; #ifdef CONFIG_AUDITSYSCALL @@ -1146,7 +1168,8 @@ out: static struct inode_operations proc_pid_link_inode_operations = { .readlink = proc_pid_readlink, - .follow_link = proc_pid_follow_link + .follow_link = proc_pid_follow_link, + .setattr = proc_setattr, }; #define NUMBUF 10 @@ -1318,6 +1341,7 @@ static struct inode *proc_pid_make_inode(struct super_block * sb, struct task_st ei->task = NULL; inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME; inode->i_ino = fake_ino(task->pid, ino); + inode->i_op = &proc_def_inode_operations; if (!pid_alive(task)) goto out_unlock; @@ -1541,11 +1565,13 @@ static struct file_operations proc_task_operations = { static struct inode_operations proc_fd_inode_operations = { .lookup = proc_lookupfd, .permission = proc_permission, + .setattr = proc_setattr, }; static struct inode_operations proc_task_inode_operations = { .lookup = proc_task_lookup, .permission = proc_task_permission, + .setattr = proc_setattr, }; #ifdef CONFIG_SECURITY @@ -1831,10 +1857,12 @@ static struct file_operations proc_tid_base_operations = { static struct inode_operations proc_tgid_base_inode_operations = { .lookup = proc_tgid_base_lookup, + .setattr = proc_setattr, }; static struct inode_operations proc_tid_base_inode_operations = { .lookup = proc_tid_base_lookup, + .setattr = proc_setattr, }; #ifdef CONFIG_SECURITY @@ -1876,10 +1904,12 @@ static struct dentry *proc_tid_attr_lookup(struct inode *dir, static struct inode_operations proc_tgid_attr_inode_operations = { .lookup = proc_tgid_attr_lookup, + .setattr = proc_setattr, }; static struct inode_operations proc_tid_attr_inode_operations = { .lookup = proc_tid_attr_lookup, + .setattr = proc_setattr, }; #endif @@ -1904,6 +1934,7 @@ static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd) static struct inode_operations proc_self_inode_operations = { .readlink = proc_self_readlink, .follow_link = proc_self_follow_link, + .setattr = proc_setattr, }; /** |