From 54e991242850edc8c53f71fa5aa3ba7a93ce38f5 Mon Sep 17 00:00:00 2001 From: Dhaval Giani Date: Fri, 27 Feb 2009 15:13:54 +0530 Subject: sched: don't allow setuid to succeed if the user does not have rt bandwidth Impact: fix hung task with certain (non-default) rt-limit settings Corey Hickey reported that on using setuid to change the uid of a rt process, the process would be unkillable and not be running. This is because there was no rt runtime for that user group. Add in a check to see if a user can attach an rt task to its task group. On failure, return EINVAL, which is also returned in CONFIG_CGROUP_SCHED. Reported-by: Corey Hickey Signed-off-by: Dhaval Giani Acked-by: Peter Zijlstra Signed-off-by: Ingo Molnar --- kernel/sys.c | 31 ++++++++++++++++++++----------- 1 file changed, 20 insertions(+), 11 deletions(-) (limited to 'kernel/sys.c') diff --git a/kernel/sys.c b/kernel/sys.c index f145c415bc1..37f458e6882 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -559,7 +559,7 @@ error: abort_creds(new); return retval; } - + /* * change the user struct in a credentials set to match the new UID */ @@ -571,6 +571,11 @@ static int set_user(struct cred *new) if (!new_user) return -EAGAIN; + if (!task_can_switch_user(new_user, current)) { + free_uid(new_user); + return -EINVAL; + } + if (atomic_read(&new_user->processes) >= current->signal->rlim[RLIMIT_NPROC].rlim_cur && new_user != INIT_USER) { @@ -631,10 +636,11 @@ SYSCALL_DEFINE2(setreuid, uid_t, ruid, uid_t, euid) goto error; } - retval = -EAGAIN; - if (new->uid != old->uid && set_user(new) < 0) - goto error; - + if (new->uid != old->uid) { + retval = set_user(new); + if (retval < 0) + goto error; + } if (ruid != (uid_t) -1 || (euid != (uid_t) -1 && euid != old->uid)) new->suid = new->euid; @@ -680,9 +686,10 @@ SYSCALL_DEFINE1(setuid, uid_t, uid) retval = -EPERM; if (capable(CAP_SETUID)) { new->suid = new->uid = uid; - if (uid != old->uid && set_user(new) < 0) { - retval = -EAGAIN; - goto error; + if (uid != old->uid) { + retval = set_user(new); + if (retval < 0) + goto error; } } else if (uid != old->uid && uid != new->suid) { goto error; @@ -734,11 +741,13 @@ SYSCALL_DEFINE3(setresuid, uid_t, ruid, uid_t, euid, uid_t, suid) goto error; } - retval = -EAGAIN; if (ruid != (uid_t) -1) { new->uid = ruid; - if (ruid != old->uid && set_user(new) < 0) - goto error; + if (ruid != old->uid) { + retval = set_user(new); + if (retval < 0) + goto error; + } } if (euid != (uid_t) -1) new->euid = euid; -- cgit v1.2.3-70-g09d2 From 5ad4e53bd5406ee214ddc5a41f03f779b8b2d526 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sun, 29 Mar 2009 19:50:06 -0400 Subject: Get rid of indirect include of fs_struct.h Don't pull it in sched.h; very few files actually need it and those can include directly. sched.h itself only needs forward declaration of struct fs_struct; Signed-off-by: Al Viro --- arch/cris/kernel/process.c | 1 - fs/dcache.c | 1 + fs/exec.c | 1 + fs/fs_struct.c | 1 + fs/namei.c | 1 + fs/namespace.c | 1 + fs/open.c | 1 + fs/proc/base.c | 1 + fs/proc/task_nommu.c | 1 + include/linux/mnt_namespace.h | 2 ++ include/linux/nsproxy.h | 1 + include/linux/sched.h | 3 ++- init/do_mounts.c | 1 + kernel/auditsc.c | 1 + kernel/exec_domain.c | 1 + kernel/exit.c | 1 + kernel/fork.c | 1 + kernel/sys.c | 1 + security/tomoyo/realpath.c | 1 + 19 files changed, 20 insertions(+), 2 deletions(-) (limited to 'kernel/sys.c') diff --git a/arch/cris/kernel/process.c b/arch/cris/kernel/process.c index 60816e87645..4df0b320d52 100644 --- a/arch/cris/kernel/process.c +++ b/arch/cris/kernel/process.c @@ -19,7 +19,6 @@ #include #include #include -#include #include #include #include diff --git a/fs/dcache.c b/fs/dcache.c index 90bbd7e1b11..0dc4de21f08 100644 --- a/fs/dcache.c +++ b/fs/dcache.c @@ -32,6 +32,7 @@ #include #include #include +#include #include "internal.h" int sysctl_vfs_cache_pressure __read_mostly = 100; diff --git a/fs/exec.c b/fs/exec.c index 614991bf0c8..052a961e41a 100644 --- a/fs/exec.c +++ b/fs/exec.c @@ -53,6 +53,7 @@ #include #include #include +#include #include #include diff --git a/fs/fs_struct.c b/fs/fs_struct.c index 6ac21933867..eee059052db 100644 --- a/fs/fs_struct.c +++ b/fs/fs_struct.c @@ -3,6 +3,7 @@ #include #include #include +#include /* * Replace the fs->{rootmnt,root} with {mnt,dentry}. Put the old values. diff --git a/fs/namei.c b/fs/namei.c index 964c0249444..b8433ebfae0 100644 --- a/fs/namei.c +++ b/fs/namei.c @@ -32,6 +32,7 @@ #include #include #include +#include #include #define ACC_MODE(x) ("\000\004\002\006"[(x)&O_ACCMODE]) diff --git a/fs/namespace.c b/fs/namespace.c index 1e56303c718..c6f54e4c429 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -27,6 +27,7 @@ #include #include #include +#include #include #include #include "pnode.h" diff --git a/fs/open.c b/fs/open.c index 75b61677daa..377eb25b6ab 100644 --- a/fs/open.c +++ b/fs/open.c @@ -29,6 +29,7 @@ #include #include #include +#include int vfs_statfs(struct dentry *dentry, struct kstatfs *buf) { diff --git a/fs/proc/base.c b/fs/proc/base.c index e0afd326b68..f71559784bf 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -80,6 +80,7 @@ #include #include #include +#include #include "internal.h" /* NOTE: diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c index 6ca01052c5b..253afc04484 100644 --- a/fs/proc/task_nommu.c +++ b/fs/proc/task_nommu.c @@ -2,6 +2,7 @@ #include #include #include +#include #include #include #include diff --git a/include/linux/mnt_namespace.h b/include/linux/mnt_namespace.h index 830bbcd449d..3a059298cc1 100644 --- a/include/linux/mnt_namespace.h +++ b/include/linux/mnt_namespace.h @@ -22,6 +22,8 @@ struct proc_mounts { int event; }; +struct fs_struct; + extern struct mnt_namespace *copy_mnt_ns(unsigned long, struct mnt_namespace *, struct fs_struct *); extern void __put_mnt_ns(struct mnt_namespace *ns); diff --git a/include/linux/nsproxy.h b/include/linux/nsproxy.h index afad7dec1b3..7b370c7cfef 100644 --- a/include/linux/nsproxy.h +++ b/include/linux/nsproxy.h @@ -8,6 +8,7 @@ struct mnt_namespace; struct uts_namespace; struct ipc_namespace; struct pid_namespace; +struct fs_struct; /* * A structure to contain pointers to all per-process diff --git a/include/linux/sched.h b/include/linux/sched.h index 29df6374d2d..b4e065ea0de 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -68,7 +68,7 @@ struct sched_param { #include #include #include -#include +#include #include #include #include @@ -97,6 +97,7 @@ struct futex_pi_state; struct robust_list_head; struct bio; struct bts_tracer; +struct fs_struct; /* * List of flags we want to share for kernel threads, diff --git a/init/do_mounts.c b/init/do_mounts.c index 8d4ff5afc1d..dd7ee5f203f 100644 --- a/init/do_mounts.c +++ b/init/do_mounts.c @@ -14,6 +14,7 @@ #include #include #include +#include #include #include diff --git a/kernel/auditsc.c b/kernel/auditsc.c index 8cbddff6c28..2bfc6478676 100644 --- a/kernel/auditsc.c +++ b/kernel/auditsc.c @@ -66,6 +66,7 @@ #include #include #include +#include #include "audit.h" diff --git a/kernel/exec_domain.c b/kernel/exec_domain.c index cb8e9626c21..c35452cadde 100644 --- a/kernel/exec_domain.c +++ b/kernel/exec_domain.c @@ -18,6 +18,7 @@ #include #include #include +#include static void default_handler(int, struct pt_regs *); diff --git a/kernel/exit.c b/kernel/exit.c index ad8375758a7..b5d656845c9 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -46,6 +46,7 @@ #include #include #include +#include #include #include diff --git a/kernel/fork.c b/kernel/fork.c index 51f138a131d..e82a14577a9 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -60,6 +60,7 @@ #include #include #include +#include #include #include diff --git a/kernel/sys.c b/kernel/sys.c index 37f458e6882..ce182aaed20 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -34,6 +34,7 @@ #include #include #include +#include #include #include diff --git a/security/tomoyo/realpath.c b/security/tomoyo/realpath.c index d47f16b844b..3bbe01a7a4b 100644 --- a/security/tomoyo/realpath.c +++ b/security/tomoyo/realpath.c @@ -12,6 +12,7 @@ #include #include #include +#include #include "common.h" #include "realpath.h" -- cgit v1.2.3-70-g09d2 From 1b0f7ffd0ea27cd3a0b9ca04e3df9522048c32a3 Mon Sep 17 00:00:00 2001 From: Oleg Nesterov Date: Thu, 2 Apr 2009 16:58:39 -0700 Subject: pids: kill signal_struct-> __pgrp/__session and friends We are wasting 2 words in signal_struct without any reason to implement task_pgrp_nr() and task_session_nr(). task_session_nr() has no callers since 2e2ba22ea4fd4bb85f0fa37c521066db6775cbef, we can remove it. task_pgrp_nr() is still (I believe wrongly) used in fs/autofsX and fs/coda. This patch reimplements task_pgrp_nr() via task_pgrp_nr_ns(), and kills __pgrp/__session and the related helpers. The change in drivers/char/tty_io.c is cosmetic, but hopefully makes sense anyway. Signed-off-by: Oleg Nesterov Acked-by: Alan Cox [tty parts] Cc: Cedric Le Goater Cc: Dave Hansen Cc: Eric Biederman Cc: Pavel Emelyanov Cc: Serge Hallyn Cc: Sukadev Bhattiprolu Cc: Roland McGrath Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/char/tty_io.c | 4 ++-- include/linux/sched.h | 43 ++++++------------------------------------- kernel/exit.c | 10 +++------- kernel/fork.c | 2 -- kernel/sys.c | 4 +--- 5 files changed, 12 insertions(+), 51 deletions(-) (limited to 'kernel/sys.c') diff --git a/drivers/char/tty_io.c b/drivers/char/tty_io.c index a44b701c5bb..66b99a2049e 100644 --- a/drivers/char/tty_io.c +++ b/drivers/char/tty_io.c @@ -2681,7 +2681,7 @@ void __do_SAK(struct tty_struct *tty) /* Kill the entire session */ do_each_pid_task(session, PIDTYPE_SID, p) { printk(KERN_NOTICE "SAK: killed process %d" - " (%s): task_session_nr(p)==tty->session\n", + " (%s): task_session(p)==tty->session\n", task_pid_nr(p), p->comm); send_sig(SIGKILL, p, 1); } while_each_pid_task(session, PIDTYPE_SID, p); @@ -2691,7 +2691,7 @@ void __do_SAK(struct tty_struct *tty) do_each_thread(g, p) { if (p->signal->tty == tty) { printk(KERN_NOTICE "SAK: killed process %d" - " (%s): task_session_nr(p)==tty->session\n", + " (%s): task_session(p)==tty->session\n", task_pid_nr(p), p->comm); send_sig(SIGKILL, p, 1); continue; diff --git a/include/linux/sched.h b/include/linux/sched.h index 49df878a0ca..206ac003e8c 100644 --- a/include/linux/sched.h +++ b/include/linux/sched.h @@ -547,25 +547,8 @@ struct signal_struct { struct list_head cpu_timers[3]; - /* job control IDs */ - - /* - * pgrp and session fields are deprecated. - * use the task_session_Xnr and task_pgrp_Xnr routines below - */ - - union { - pid_t pgrp __deprecated; - pid_t __pgrp; - }; - struct pid *tty_old_pgrp; - union { - pid_t session __deprecated; - pid_t __session; - }; - /* boolean value for session group leader */ int leader; @@ -1469,16 +1452,6 @@ static inline int rt_task(struct task_struct *p) return rt_prio(p->prio); } -static inline void set_task_session(struct task_struct *tsk, pid_t session) -{ - tsk->signal->__session = session; -} - -static inline void set_task_pgrp(struct task_struct *tsk, pid_t pgrp) -{ - tsk->signal->__pgrp = pgrp; -} - static inline struct pid *task_pid(struct task_struct *task) { return task->pids[PIDTYPE_PID].pid; @@ -1552,11 +1525,6 @@ static inline pid_t task_tgid_vnr(struct task_struct *tsk) } -static inline pid_t task_pgrp_nr(struct task_struct *tsk) -{ - return tsk->signal->__pgrp; -} - static inline pid_t task_pgrp_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) { @@ -1569,11 +1537,6 @@ static inline pid_t task_pgrp_vnr(struct task_struct *tsk) } -static inline pid_t task_session_nr(struct task_struct *tsk) -{ - return tsk->signal->__session; -} - static inline pid_t task_session_nr_ns(struct task_struct *tsk, struct pid_namespace *ns) { @@ -1585,6 +1548,12 @@ static inline pid_t task_session_vnr(struct task_struct *tsk) return __task_pid_nr_ns(tsk, PIDTYPE_SID, NULL); } +/* obsolete, do not use */ +static inline pid_t task_pgrp_nr(struct task_struct *tsk) +{ + return task_pgrp_nr_ns(tsk, &init_pid_ns); +} + /** * pid_alive - check that a task structure is not stale * @p: Task structure to be checked. diff --git a/kernel/exit.c b/kernel/exit.c index 384f09caf2e..3bec141c82f 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -357,16 +357,12 @@ static void reparent_to_kthreadd(void) void __set_special_pids(struct pid *pid) { struct task_struct *curr = current->group_leader; - pid_t nr = pid_nr(pid); - if (task_session(curr) != pid) { + if (task_session(curr) != pid) change_pid(curr, PIDTYPE_SID, pid); - set_task_session(curr, nr); - } - if (task_pgrp(curr) != pid) { + + if (task_pgrp(curr) != pid) change_pid(curr, PIDTYPE_PGID, pid); - set_task_pgrp(curr, nr); - } } static void set_special_pids(struct pid *pid) diff --git a/kernel/fork.c b/kernel/fork.c index adbea16ec64..f7445823144 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1265,8 +1265,6 @@ static struct task_struct *copy_process(unsigned long clone_flags, p->signal->leader_pid = pid; tty_kref_put(p->signal->tty); p->signal->tty = tty_kref_get(current->signal->tty); - set_task_pgrp(p, task_pgrp_nr(current)); - set_task_session(p, task_session_nr(current)); attach_pid(p, PIDTYPE_PGID, task_pgrp(current)); attach_pid(p, PIDTYPE_SID, task_session(current)); list_add_tail_rcu(&p->tasks, &init_task.tasks); diff --git a/kernel/sys.c b/kernel/sys.c index 37f458e6882..742cefa527e 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1013,10 +1013,8 @@ SYSCALL_DEFINE2(setpgid, pid_t, pid, pid_t, pgid) if (err) goto out; - if (task_pgrp(p) != pgrp) { + if (task_pgrp(p) != pgrp) change_pid(p, PIDTYPE_PGID, pgrp); - set_task_pgrp(p, pid_nr(pgrp)); - } err = 0; out: -- cgit v1.2.3-70-g09d2