diff options
Diffstat (limited to 'kernel/seccomp.c')
-rw-r--r-- | kernel/seccomp.c | 16 |
1 files changed, 15 insertions, 1 deletions
diff --git a/kernel/seccomp.c b/kernel/seccomp.c index 58125160417c..d5543e787e4e 100644 --- a/kernel/seccomp.c +++ b/kernel/seccomp.c @@ -199,6 +199,8 @@ static u32 seccomp_run_filters(int syscall) static inline bool seccomp_may_assign_mode(unsigned long seccomp_mode) { + BUG_ON(!spin_is_locked(¤t->sighand->siglock)); + if (current->seccomp.mode && current->seccomp.mode != seccomp_mode) return false; @@ -207,6 +209,8 @@ static inline bool seccomp_may_assign_mode(unsigned long seccomp_mode) static inline void seccomp_assign_mode(unsigned long seccomp_mode) { + BUG_ON(!spin_is_locked(¤t->sighand->siglock)); + current->seccomp.mode = seccomp_mode; set_tsk_thread_flag(current, TIF_SECCOMP); } @@ -332,6 +336,8 @@ out: * @flags: flags to change filter behavior * @filter: seccomp filter to add to the current process * + * Caller must be holding current->sighand->siglock lock. + * * Returns 0 on success, -ve on error. */ static long seccomp_attach_filter(unsigned int flags, @@ -340,6 +346,8 @@ static long seccomp_attach_filter(unsigned int flags, unsigned long total_insns; struct seccomp_filter *walker; + BUG_ON(!spin_is_locked(¤t->sighand->siglock)); + /* Validate resulting filter length. */ total_insns = filter->prog->len; for (walker = current->seccomp.filter; walker; walker = walker->prev) @@ -529,6 +537,8 @@ static long seccomp_set_mode_strict(void) const unsigned long seccomp_mode = SECCOMP_MODE_STRICT; long ret = -EINVAL; + spin_lock_irq(¤t->sighand->siglock); + if (!seccomp_may_assign_mode(seccomp_mode)) goto out; @@ -539,6 +549,7 @@ static long seccomp_set_mode_strict(void) ret = 0; out: + spin_unlock_irq(¤t->sighand->siglock); return ret; } @@ -566,13 +577,15 @@ static long seccomp_set_mode_filter(unsigned int flags, /* Validate flags. */ if (flags != 0) - goto out; + return -EINVAL; /* Prepare the new filter before holding any locks. */ prepared = seccomp_prepare_user_filter(filter); if (IS_ERR(prepared)) return PTR_ERR(prepared); + spin_lock_irq(¤t->sighand->siglock); + if (!seccomp_may_assign_mode(seccomp_mode)) goto out; @@ -584,6 +597,7 @@ static long seccomp_set_mode_filter(unsigned int flags, seccomp_assign_mode(seccomp_mode); out: + spin_unlock_irq(¤t->sighand->siglock); seccomp_filter_free(prepared); return ret; } |