From 282b6f3a2d1c95ed2443ad974e354883b66cd7c9 Mon Sep 17 00:00:00 2001 From: Jiri Slaby Date: Wed, 26 Aug 2009 23:45:34 +0200 Subject: [PATCH] core: split sys_setrlimit References: FATE#305733 Patch-mainline: no (later) Create do_setrlimit from sys_setrlimit and declare do_setrlimit in the resource header. This is to allow rlimits to be changed not only by syscall, but later from proc and syscall code too. Signed-off-by: Jiri Slaby --- include/linux/resource.h | 2 ++ kernel/sys.c | 40 ++++++++++++++++++++++++---------------- 2 files changed, 26 insertions(+), 16 deletions(-) --- a/include/linux/resource.h +++ b/include/linux/resource.h @@ -73,6 +73,8 @@ struct rlimit { 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); #endif /* __KERNEL__ */ --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1302,42 +1302,41 @@ SYSCALL_DEFINE2(old_getrlimit, unsigned #endif -SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) +int do_setrlimit(struct task_struct *tsk, unsigned int resource, + struct rlimit *new_rlim) { - struct rlimit new_rlim, *old_rlim; + struct rlimit *old_rlim; int retval; if (resource >= RLIM_NLIMITS) return -EINVAL; - if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) - return -EFAULT; - if (new_rlim.rlim_cur > new_rlim.rlim_max) + if (new_rlim->rlim_cur > new_rlim->rlim_max) return -EINVAL; - if (resource == RLIMIT_NOFILE && new_rlim.rlim_max > sysctl_nr_open) + if (resource == RLIMIT_NOFILE && new_rlim->rlim_max > sysctl_nr_open) return -EPERM; - retval = security_task_setrlimit(current, resource, &new_rlim); + retval = security_task_setrlimit(tsk, resource, new_rlim); if (retval) return retval; - if (resource == RLIMIT_CPU && new_rlim.rlim_cur == 0) { + 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; + new_rlim->rlim_cur = 1; } - old_rlim = current->signal->rlim + resource; - task_lock(current->group_leader); - if ((new_rlim.rlim_max <= old_rlim->rlim_max) || + old_rlim = tsk->signal->rlim + resource; + task_lock(tsk->group_leader); + if ((new_rlim->rlim_max <= old_rlim->rlim_max) || capable(CAP_SYS_RESOURCE)) - *old_rlim = new_rlim; + *old_rlim = *new_rlim; else retval = -EPERM; - task_unlock(current->group_leader); + task_unlock(tsk->group_leader); if (retval || resource != RLIMIT_CPU) goto out; @@ -1348,14 +1347,23 @@ SYSCALL_DEFINE2(setrlimit, unsigned int, * very long-standing error, and fixing it now risks breakage of * applications, so we live with it */ - if (new_rlim.rlim_cur == RLIM_INFINITY) + if (new_rlim->rlim_cur == RLIM_INFINITY) goto out; - update_rlimit_cpu(current, new_rlim.rlim_cur); + update_rlimit_cpu(tsk, new_rlim->rlim_cur); out: return retval; } +SYSCALL_DEFINE2(setrlimit, unsigned int, resource, struct rlimit __user *, rlim) +{ + struct rlimit new_rlim; + + if (copy_from_user(&new_rlim, rlim, sizeof(*rlim))) + return -EFAULT; + return do_setrlimit(current, resource, &new_rlim); +} + /* * It would make sense to put struct rusage in the task_struct, * except that would make the task_struct be *really big*. After