diff options
| -rw-r--r-- | include/linux/resource.h | 4 | ||||
| -rw-r--r-- | kernel/sys.c | 71 |
2 files changed, 39 insertions, 36 deletions
diff --git a/include/linux/resource.h b/include/linux/resource.h index 037aa7e..88d36f9 100644 --- a/include/linux/resource.h +++ b/include/linux/resource.h @@ -80,8 +80,8 @@ struct rlimit64 { struct task_struct; int getrusage(struct task_struct *p, int who, struct rusage __user *ru); -int do_setrlimit(struct task_struct *tsk, unsigned int resource, - struct rlimit *new_rlim); +int do_prlimit(struct task_struct *tsk, unsigned int resource, + struct rlimit *new_rlim, struct rlimit *old_rlim); #endif /* __KERNEL__ */ diff --git a/kernel/sys.c b/kernel/sys.c index c762eeb..bc7d1be 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1273,18 +1273,21 @@ SYSCALL_DEFINE2(old_getrlimit, unsigned int, resource, #endif /* make sure you are allowed to change @tsk limits before calling this */ -int do_setrlimit(struct task_struct *tsk, unsigned int resource, - struct rlimit *new_rlim) +int do_prlimit(struct task_struct *tsk, unsigned int resource, + struct rlimit *new_rlim, struct rlimit *old_rlim) { - struct rlimit *old_rlim; + struct rlimit *rlim; int retval = 0; if (resource >= RLIM_NLIMITS) return -EINVAL; - if (new_rlim->rlim_cur > new_rlim->rlim_max) - return -EINVAL; - if (resource == RLIMIT_NOFILE && new_rlim->rlim_max > sysctl_nr_open) - return -EPERM; + if (new_rlim) { + if (new_rlim->rlim_cur > new_rlim->rlim_max) + return -EINVAL; + if (resource == RLIMIT_NOFILE && + new_rlim->rlim_max > sysctl_nr_open) + return -EPERM; + } /* protect tsk->signal and tsk->sighand from disappearing */ read_lock(&tasklist_lock); @@ -1293,42 +1296,42 @@ int do_setrlimit(struct task_struct *tsk, unsigned int resource, goto out; } - old_rlim = tsk->signal->rlim + resource; + rlim = tsk->signal->rlim + resource; task_lock(tsk->group_leader); - if (new_rlim->rlim_max > old_rlim->rlim_max && - !capable(CAP_SYS_RESOURCE)) - retval = -EPERM; - if (!retval) - retval = security_task_setrlimit(tsk->group_leader, resource, - new_rlim); - - if (resource == RLIMIT_CPU && new_rlim->rlim_cur == 0) { - /* - * The caller is asking for an immediate RLIMIT_CPU - * expiry. But we use the zero value to mean "it was - * never set". So let's cheat and make it one second - * instead - */ - new_rlim->rlim_cur = 1; + if (new_rlim) { + if (new_rlim->rlim_max > rlim->rlim_max && + !capable(CAP_SYS_RESOURCE)) + retval = -EPERM; + if (!retval) + retval = security_task_setrlimit(tsk->group_leader, + resource, new_rlim); + if (resource == RLIMIT_CPU && new_rlim->rlim_cur == 0) { + /* + * The caller is asking for an immediate RLIMIT_CPU + * expiry. But we use the zero value to mean "it was + * never set". So let's cheat and make it one second + * instead + */ + new_rlim->rlim_cur = 1; + } + } + if (!retval) { + if (old_rlim) + *old_rlim = *rlim; + if (new_rlim) + *rlim = *new_rlim; } - - if (!retval) - *old_rlim = *new_rlim; task_unlock(tsk->group_leader); - if (retval || resource != RLIMIT_CPU) - goto out; - /* * RLIMIT_CPU handling. Note that the kernel fails to return an error * code if it rejected the user's attempt to set RLIMIT_CPU. This is a * very long-standing error, and fixing it now risks breakage of * applications, so we live with it */ - if (new_rlim->rlim_cur == RLIM_INFINITY) - goto out; - - update_rlimit_cpu(tsk, new_rlim->rlim_cur); + if (!retval && new_rlim && resource == RLIMIT_CPU && + new_rlim->rlim_cur != RLIM_INFINITY) + update_rlimit_cpu(tsk, new_rlim->rlim_cur); out: read_unlock(&tasklist_lock); return retval; @@ -1340,7 +1343,7 @@ SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) return -EFAULT; - return do_setrlimit(current, resource, &new_rlim); + return do_prlimit(current, resource, &new_rlim, NULL); } /* |