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authorLinus Torvalds <torvalds@linux-foundation.org>2009-02-06 18:52:55 -0800
committerLinus Torvalds <torvalds@linux-foundation.org>2009-02-06 18:52:55 -0800
commitccfef64621ef1e8c7726581b38eb8b98fd2a8afb (patch)
tree74d99dcecbd7adad1dcd5d61fac408855b43a267
parentae1a25da8448271a99745da03100d5299575a269 (diff)
parent0bf2f3aec5474da80a60e1baca629af87ecb67b6 (diff)
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/security-testing-2.6: CRED: Fix SUID exec regression
-rw-r--r--fs/compat.c2
-rw-r--r--fs/exec.c28
-rw-r--r--fs/internal.h2
3 files changed, 24 insertions, 8 deletions
diff --git a/fs/compat.c b/fs/compat.c
index 65a070e705a..d0145ca2757 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -1407,7 +1407,7 @@ int compat_do_execve(char * filename,
bprm->cred = prepare_exec_creds();
if (!bprm->cred)
goto out_unlock;
- check_unsafe_exec(bprm);
+ check_unsafe_exec(bprm, current->files);
file = open_exec(filename);
retval = PTR_ERR(file);
diff --git a/fs/exec.c b/fs/exec.c
index 0dd60a01f1b..929b58004b7 100644
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1049,16 +1049,32 @@ 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)
+void check_unsafe_exec(struct linux_binprm *bprm, struct files_struct *files)
{
- struct task_struct *p = current;
+ struct task_struct *p = current, *t;
+ unsigned long flags;
+ unsigned n_fs, n_files, n_sighand;
bprm->unsafe = tracehook_unsafe_exec(p);
- if (atomic_read(&p->fs->count) > 1 ||
- atomic_read(&p->files->count) > 1 ||
- atomic_read(&p->sighand->count) > 1)
+ n_fs = 1;
+ n_files = 1;
+ n_sighand = 1;
+ 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)
bprm->unsafe |= LSM_UNSAFE_SHARE;
+
+ unlock_task_sighand(p, &flags);
}
/*
@@ -1273,7 +1289,7 @@ int do_execve(char * filename,
bprm->cred = prepare_exec_creds();
if (!bprm->cred)
goto out_unlock;
- check_unsafe_exec(bprm);
+ check_unsafe_exec(bprm, displaced);
file = open_exec(filename);
retval = PTR_ERR(file);
diff --git a/fs/internal.h b/fs/internal.h
index 53af885f173..0d8ac497b3d 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -43,7 +43,7 @@ extern void __init chrdev_init(void);
/*
* exec.c
*/
-extern void check_unsafe_exec(struct linux_binprm *);
+extern void check_unsafe_exec(struct linux_binprm *, struct files_struct *);
/*
* namespace.c