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-rw-r--r--fs/exec.c52
1 files changed, 40 insertions, 12 deletions
diff --git a/fs/exec.c b/fs/exec.c
index af1600c..e015c0b 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -46,6 +46,7 @@
#include <linux/proc_fs.h>
#include <linux/mount.h>
#include <linux/security.h>
+#include <linux/ima.h>
#include <linux/syscalls.h>
#include <linux/tsacct_kern.h>
#include <linux/cn_proc.h>
@@ -53,6 +54,7 @@
#include <linux/tracehook.h>
#include <linux/kmod.h>
#include <linux/fsnotify.h>
+#include <linux/fs_struct.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
@@ -128,6 +130,9 @@ SYSCALL_DEFINE1(uselib, const char __user *, library)
MAY_READ | MAY_EXEC | MAY_OPEN);
if (error)
goto exit;
+ error = ima_path_check(&nd.path, MAY_READ | MAY_EXEC | MAY_OPEN);
+ if (error)
+ goto exit;
file = nameidata_to_filp(&nd, O_RDONLY|O_LARGEFILE);
error = PTR_ERR(file);
@@ -675,6 +680,9 @@ struct file *open_exec(const char *name)
err = inode_permission(nd.path.dentry->d_inode, MAY_EXEC | MAY_OPEN);
if (err)
goto out_path_put;
+ err = ima_path_check(&nd.path, MAY_EXEC | MAY_OPEN);
+ if (err)
+ goto out_path_put;
file = nameidata_to_filp(&nd, O_RDONLY|O_LARGEFILE);
if (IS_ERR(file))
@@ -1057,32 +1065,35 @@ EXPORT_SYMBOL(install_exec_creds);
* - the caller must hold current->cred_exec_mutex to protect against
* PTRACE_ATTACH
*/
-void check_unsafe_exec(struct linux_binprm *bprm, struct files_struct *files)
+int check_unsafe_exec(struct linux_binprm *bprm)
{
struct task_struct *p = current, *t;
unsigned long flags;
- unsigned n_fs, n_files, n_sighand;
+ unsigned n_fs;
+ int res = 0;
bprm->unsafe = tracehook_unsafe_exec(p);
n_fs = 1;
- n_files = 1;
- n_sighand = 1;
+ write_lock(&p->fs->lock);
lock_task_sighand(p, &flags);
for (t = next_thread(p); t != p; t = next_thread(t)) {
if (t->fs == p->fs)
n_fs++;
- if (t->files == files)
- n_files++;
- n_sighand++;
}
- if (atomic_read(&p->fs->count) > n_fs ||
- atomic_read(&p->files->count) > n_files ||
- atomic_read(&p->sighand->count) > n_sighand)
+ if (p->fs->users > n_fs) {
bprm->unsafe |= LSM_UNSAFE_SHARE;
+ } else {
+ if (p->fs->in_exec)
+ res = -EAGAIN;
+ p->fs->in_exec = 1;
+ }
unlock_task_sighand(p, &flags);
+ write_unlock(&p->fs->lock);
+
+ return res;
}
/*
@@ -1192,6 +1203,9 @@ int search_binary_handler(struct linux_binprm *bprm,struct pt_regs *regs)
retval = security_bprm_check(bprm);
if (retval)
return retval;
+ retval = ima_bprm_check(bprm);
+ if (retval)
+ return retval;
/* kernel module loader fixup */
/* so we don't try to load run modprobe in kernel space. */
@@ -1292,17 +1306,21 @@ int do_execve(char * filename,
retval = mutex_lock_interruptible(&current->cred_exec_mutex);
if (retval < 0)
goto out_free;
+ current->in_execve = 1;
retval = -ENOMEM;
bprm->cred = prepare_exec_creds();
if (!bprm->cred)
goto out_unlock;
- check_unsafe_exec(bprm, displaced);
+
+ retval = check_unsafe_exec(bprm);
+ if (retval)
+ goto out_unlock;
file = open_exec(filename);
retval = PTR_ERR(file);
if (IS_ERR(file))
- goto out_unlock;
+ goto out_unmark;
sched_exec();
@@ -1345,6 +1363,10 @@ int do_execve(char * filename,
goto out;
/* execve succeeded */
+ write_lock(&current->fs->lock);
+ current->fs->in_exec = 0;
+ write_unlock(&current->fs->lock);
+ current->in_execve = 0;
mutex_unlock(&current->cred_exec_mutex);
acct_update_integrals(current);
free_bprm(bprm);
@@ -1362,7 +1384,13 @@ out_file:
fput(bprm->file);
}
+out_unmark:
+ write_lock(&current->fs->lock);
+ current->fs->in_exec = 0;
+ write_unlock(&current->fs->lock);
+
out_unlock:
+ current->in_execve = 0;
mutex_unlock(&current->cred_exec_mutex);
out_free:
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