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Diffstat (limited to 'fs/exec.c')
-rw-r--r--fs/exec.c130
1 files changed, 55 insertions, 75 deletions
diff --git a/fs/exec.c b/fs/exec.c
index 052a961e41aa..e639957d7a57 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -33,6 +33,7 @@
#include <linux/string.h>
#include <linux/init.h>
#include <linux/pagemap.h>
+#include <linux/perf_counter.h>
#include <linux/highmem.h>
#include <linux/spinlock.h>
#include <linux/key.h>
@@ -69,17 +70,18 @@ int suid_dumpable = 0;
static LIST_HEAD(formats);
static DEFINE_RWLOCK(binfmt_lock);
-int register_binfmt(struct linux_binfmt * fmt)
+int __register_binfmt(struct linux_binfmt * fmt, int insert)
{
if (!fmt)
return -EINVAL;
write_lock(&binfmt_lock);
- list_add(&fmt->lh, &formats);
+ insert ? list_add(&fmt->lh, &formats) :
+ list_add_tail(&fmt->lh, &formats);
write_unlock(&binfmt_lock);
return 0;
}
-EXPORT_SYMBOL(register_binfmt);
+EXPORT_SYMBOL(__register_binfmt);
void unregister_binfmt(struct linux_binfmt * fmt)
{
@@ -104,40 +106,28 @@ static inline void put_binfmt(struct linux_binfmt * fmt)
SYSCALL_DEFINE1(uselib, const char __user *, library)
{
struct file *file;
- struct nameidata nd;
char *tmp = getname(library);
int error = PTR_ERR(tmp);
- if (!IS_ERR(tmp)) {
- error = path_lookup_open(AT_FDCWD, tmp,
- LOOKUP_FOLLOW, &nd,
- FMODE_READ|FMODE_EXEC);
- putname(tmp);
- }
- if (error)
+ if (IS_ERR(tmp))
+ goto out;
+
+ file = do_filp_open(AT_FDCWD, tmp,
+ O_LARGEFILE | O_RDONLY | FMODE_EXEC, 0,
+ MAY_READ | MAY_EXEC | MAY_OPEN);
+ putname(tmp);
+ error = PTR_ERR(file);
+ if (IS_ERR(file))
goto out;
error = -EINVAL;
- if (!S_ISREG(nd.path.dentry->d_inode->i_mode))
+ if (!S_ISREG(file->f_path.dentry->d_inode->i_mode))
goto exit;
error = -EACCES;
- if (nd.path.mnt->mnt_flags & MNT_NOEXEC)
+ if (file->f_path.mnt->mnt_flags & MNT_NOEXEC)
goto exit;
- error = inode_permission(nd.path.dentry->d_inode,
- 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);
- if (IS_ERR(file))
- goto out;
-
fsnotify_open(file->f_path.dentry);
error = -ENOEXEC;
@@ -159,13 +149,10 @@ SYSCALL_DEFINE1(uselib, const char __user *, library)
}
read_unlock(&binfmt_lock);
}
+exit:
fput(file);
out:
return error;
-exit:
- release_open_intent(&nd);
- path_put(&nd.path);
- goto out;
}
#ifdef CONFIG_MMU
@@ -660,47 +647,33 @@ EXPORT_SYMBOL(setup_arg_pages);
struct file *open_exec(const char *name)
{
- struct nameidata nd;
struct file *file;
int err;
- err = path_lookup_open(AT_FDCWD, name, LOOKUP_FOLLOW, &nd,
- FMODE_READ|FMODE_EXEC);
- if (err)
+ file = do_filp_open(AT_FDCWD, name,
+ O_LARGEFILE | O_RDONLY | FMODE_EXEC, 0,
+ MAY_EXEC | MAY_OPEN);
+ if (IS_ERR(file))
goto out;
err = -EACCES;
- if (!S_ISREG(nd.path.dentry->d_inode->i_mode))
- goto out_path_put;
-
- if (nd.path.mnt->mnt_flags & MNT_NOEXEC)
- goto out_path_put;
-
- 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;
+ if (!S_ISREG(file->f_path.dentry->d_inode->i_mode))
+ goto exit;
- file = nameidata_to_filp(&nd, O_RDONLY|O_LARGEFILE);
- if (IS_ERR(file))
- return file;
+ if (file->f_path.mnt->mnt_flags & MNT_NOEXEC)
+ goto exit;
fsnotify_open(file->f_path.dentry);
err = deny_write_access(file);
- if (err) {
- fput(file);
- goto out;
- }
+ if (err)
+ goto exit;
+out:
return file;
- out_path_put:
- release_open_intent(&nd);
- path_put(&nd.path);
- out:
+exit:
+ fput(file);
return ERR_PTR(err);
}
EXPORT_SYMBOL(open_exec);
@@ -950,6 +923,7 @@ void set_task_comm(struct task_struct *tsk, char *buf)
task_lock(tsk);
strlcpy(tsk->comm, buf, sizeof(tsk->comm));
task_unlock(tsk);
+ perf_counter_comm(tsk);
}
int flush_old_exec(struct linux_binprm * bprm)
@@ -1018,6 +992,13 @@ int flush_old_exec(struct linux_binprm * bprm)
current->personality &= ~bprm->per_clear;
+ /*
+ * Flush performance counters when crossing a
+ * security domain:
+ */
+ if (!get_dumpable(current->mm))
+ perf_counter_exit_task(current);
+
/* An exec changes our domain. We are no longer part of the thread
group */
@@ -1044,7 +1025,7 @@ void install_exec_creds(struct linux_binprm *bprm)
commit_creds(bprm->cred);
bprm->cred = NULL;
- /* cred_exec_mutex must be held at least to this point to prevent
+ /* cred_guard_mutex must be held at least to this point to prevent
* ptrace_attach() from altering our determination of the task's
* credentials; any time after this it may be unlocked */
@@ -1054,13 +1035,12 @@ EXPORT_SYMBOL(install_exec_creds);
/*
* determine how safe it is to execute the proposed program
- * - the caller must hold current->cred_exec_mutex to protect against
+ * - the caller must hold current->cred_guard_mutex to protect against
* PTRACE_ATTACH
*/
int check_unsafe_exec(struct linux_binprm *bprm)
{
struct task_struct *p = current, *t;
- unsigned long flags;
unsigned n_fs;
int res = 0;
@@ -1068,21 +1048,22 @@ int check_unsafe_exec(struct linux_binprm *bprm)
n_fs = 1;
write_lock(&p->fs->lock);
- lock_task_sighand(p, &flags);
+ rcu_read_lock();
for (t = next_thread(p); t != p; t = next_thread(t)) {
if (t->fs == p->fs)
n_fs++;
}
+ rcu_read_unlock();
if (p->fs->users > n_fs) {
bprm->unsafe |= LSM_UNSAFE_SHARE;
} else {
- if (p->fs->in_exec)
- res = -EAGAIN;
- p->fs->in_exec = 1;
+ res = -EAGAIN;
+ if (!p->fs->in_exec) {
+ p->fs->in_exec = 1;
+ res = 1;
+ }
}
-
- unlock_task_sighand(p, &flags);
write_unlock(&p->fs->lock);
return res;
@@ -1284,6 +1265,7 @@ int do_execve(char * filename,
struct linux_binprm *bprm;
struct file *file;
struct files_struct *displaced;
+ bool clear_in_exec;
int retval;
retval = unshare_files(&displaced);
@@ -1295,7 +1277,7 @@ int do_execve(char * filename,
if (!bprm)
goto out_files;
- retval = mutex_lock_interruptible(&current->cred_exec_mutex);
+ retval = mutex_lock_interruptible(&current->cred_guard_mutex);
if (retval < 0)
goto out_free;
current->in_execve = 1;
@@ -1306,8 +1288,9 @@ int do_execve(char * filename,
goto out_unlock;
retval = check_unsafe_exec(bprm);
- if (retval)
+ if (retval < 0)
goto out_unlock;
+ clear_in_exec = retval;
file = open_exec(filename);
retval = PTR_ERR(file);
@@ -1355,11 +1338,9 @@ 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);
+ mutex_unlock(&current->cred_guard_mutex);
acct_update_integrals(current);
free_bprm(bprm);
if (displaced)
@@ -1377,13 +1358,12 @@ out_file:
}
out_unmark:
- write_lock(&current->fs->lock);
- current->fs->in_exec = 0;
- write_unlock(&current->fs->lock);
+ if (clear_in_exec)
+ current->fs->in_exec = 0;
out_unlock:
current->in_execve = 0;
- mutex_unlock(&current->cred_exec_mutex);
+ mutex_unlock(&current->cred_guard_mutex);
out_free:
free_bprm(bprm);
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-12 09:15:07 +0000