Blame view
kernel/futex_compat.c
4.44 KB
34f192c65 [PATCH] lightweig... |
1 2 3 4 5 6 7 8 9 10 |
/* * linux/kernel/futex_compat.c * * Futex compatibililty routines. * * Copyright 2006, Red Hat, Inc., Ingo Molnar */ #include <linux/linkage.h> #include <linux/compat.h> |
b488893a3 pid namespaces: c... |
11 |
#include <linux/nsproxy.h> |
34f192c65 [PATCH] lightweig... |
12 13 14 |
#include <linux/futex.h> #include <asm/uaccess.h> |
e3f2ddeac [PATCH] pi-futex:... |
15 16 17 18 19 20 |
/* * Fetch a robust-list pointer. Bit 0 signals PI futexes: */ static inline int fetch_robust_entry(compat_uptr_t *uentry, struct robust_list __user **entry, |
ba46df984 [PATCH] __user an... |
21 |
compat_uptr_t __user *head, int *pi) |
e3f2ddeac [PATCH] pi-futex:... |
22 23 24 25 26 27 28 29 30 |
{ if (get_user(*uentry, head)) return -EFAULT; *entry = compat_ptr((*uentry) & ~1); *pi = (unsigned int)(*uentry) & 1; return 0; } |
8481664d3 futex_compat __us... |
31 |
static void __user *futex_uaddr(struct robust_list __user *entry, |
3c5fd9c77 [FUTEX] Fix addre... |
32 33 34 35 36 37 38 |
compat_long_t futex_offset) { compat_uptr_t base = ptr_to_compat(entry); void __user *uaddr = compat_ptr(base + futex_offset); return uaddr; } |
34f192c65 [PATCH] lightweig... |
39 40 41 42 43 44 45 46 47 |
/* * Walk curr->robust_list (very carefully, it's a userspace list!) * and mark any locks found there dead, and notify any waiters. * * We silently return on any sign of list-walking problem. */ void compat_exit_robust_list(struct task_struct *curr) { struct compat_robust_list_head __user *head = curr->compat_robust_list; |
9f96cb1e8 robust futex thre... |
48 49 50 |
struct robust_list __user *entry, *next_entry, *pending; unsigned int limit = ROBUST_LIST_LIMIT, pi, next_pi, pip; compat_uptr_t uentry, next_uentry, upending; |
34f192c65 [PATCH] lightweig... |
51 |
compat_long_t futex_offset; |
9f96cb1e8 robust futex thre... |
52 |
int rc; |
34f192c65 [PATCH] lightweig... |
53 |
|
a0c1e9073 futex: runtime en... |
54 55 |
if (!futex_cmpxchg_enabled) return; |
34f192c65 [PATCH] lightweig... |
56 57 58 59 |
/* * Fetch the list head (which was registered earlier, via * sys_set_robust_list()): */ |
e3f2ddeac [PATCH] pi-futex:... |
60 |
if (fetch_robust_entry(&uentry, &entry, &head->list.next, &pi)) |
34f192c65 [PATCH] lightweig... |
61 |
return; |
34f192c65 [PATCH] lightweig... |
62 63 64 65 66 67 68 69 70 |
/* * Fetch the relative futex offset: */ if (get_user(futex_offset, &head->futex_offset)) return; /* * Fetch any possibly pending lock-add first, and handle it * if it exists: */ |
e3f2ddeac [PATCH] pi-futex:... |
71 |
if (fetch_robust_entry(&upending, &pending, |
ce2c6b538 [PATCH] futex: Ap... |
72 |
&head->list_op_pending, &pip)) |
34f192c65 [PATCH] lightweig... |
73 |
return; |
34f192c65 [PATCH] lightweig... |
74 |
|
9f96cb1e8 robust futex thre... |
75 |
next_entry = NULL; /* avoid warning with gcc */ |
179c85ea5 futex_compat: fix... |
76 |
while (entry != (struct robust_list __user *) &head->list) { |
34f192c65 [PATCH] lightweig... |
77 |
/* |
9f96cb1e8 robust futex thre... |
78 79 80 81 82 83 |
* Fetch the next entry in the list before calling * handle_futex_death: */ rc = fetch_robust_entry(&next_uentry, &next_entry, (compat_uptr_t __user *)&entry->next, &next_pi); /* |
34f192c65 [PATCH] lightweig... |
84 85 86 |
* A pending lock might already be on the list, so * dont process it twice: */ |
3c5fd9c77 [FUTEX] Fix addre... |
87 88 |
if (entry != pending) { void __user *uaddr = futex_uaddr(entry, futex_offset); |
34f192c65 [PATCH] lightweig... |
89 |
|
3c5fd9c77 [FUTEX] Fix addre... |
90 91 92 |
if (handle_futex_death(uaddr, curr, pi)) return; } |
9f96cb1e8 robust futex thre... |
93 |
if (rc) |
34f192c65 [PATCH] lightweig... |
94 |
return; |
9f96cb1e8 robust futex thre... |
95 96 97 |
uentry = next_uentry; entry = next_entry; pi = next_pi; |
34f192c65 [PATCH] lightweig... |
98 99 100 101 102 103 104 105 |
/* * Avoid excessively long or circular lists: */ if (!--limit) break; cond_resched(); } |
3c5fd9c77 [FUTEX] Fix addre... |
106 107 108 109 110 |
if (pending) { void __user *uaddr = futex_uaddr(pending, futex_offset); handle_futex_death(uaddr, curr, pip); } |
34f192c65 [PATCH] lightweig... |
111 112 113 114 115 116 |
} asmlinkage long compat_sys_set_robust_list(struct compat_robust_list_head __user *head, compat_size_t len) { |
a0c1e9073 futex: runtime en... |
117 118 |
if (!futex_cmpxchg_enabled) return -ENOSYS; |
34f192c65 [PATCH] lightweig... |
119 120 121 122 123 124 125 126 127 |
if (unlikely(len != sizeof(*head))) return -EINVAL; current->compat_robust_list = head; return 0; } asmlinkage long |
ba46df984 [PATCH] __user an... |
128 |
compat_sys_get_robust_list(int pid, compat_uptr_t __user *head_ptr, |
34f192c65 [PATCH] lightweig... |
129 130 |
compat_size_t __user *len_ptr) { |
ba46df984 [PATCH] __user an... |
131 |
struct compat_robust_list_head __user *head; |
34f192c65 [PATCH] lightweig... |
132 |
unsigned long ret; |
c69e8d9c0 CRED: Use RCU to ... |
133 |
const struct cred *cred = current_cred(), *pcred; |
34f192c65 [PATCH] lightweig... |
134 |
|
a0c1e9073 futex: runtime en... |
135 136 |
if (!futex_cmpxchg_enabled) return -ENOSYS; |
34f192c65 [PATCH] lightweig... |
137 138 139 140 141 142 143 |
if (!pid) head = current->compat_robust_list; else { struct task_struct *p; ret = -ESRCH; read_lock(&tasklist_lock); |
228ebcbe6 Uninline find_tas... |
144 |
p = find_task_by_vpid(pid); |
34f192c65 [PATCH] lightweig... |
145 146 147 |
if (!p) goto err_unlock; ret = -EPERM; |
c69e8d9c0 CRED: Use RCU to ... |
148 149 150 |
pcred = __task_cred(p); if (cred->euid != pcred->euid && cred->euid != pcred->uid && |
b6dff3ec5 CRED: Separate ta... |
151 |
!capable(CAP_SYS_PTRACE)) |
34f192c65 [PATCH] lightweig... |
152 153 154 155 156 157 158 159 160 161 162 163 164 165 |
goto err_unlock; head = p->compat_robust_list; read_unlock(&tasklist_lock); } if (put_user(sizeof(*head), len_ptr)) return -EFAULT; return put_user(ptr_to_compat(head), head_ptr); err_unlock: read_unlock(&tasklist_lock); return ret; } |
8f17d3a50 [PATCH] lightweig... |
166 |
asmlinkage long compat_sys_futex(u32 __user *uaddr, int op, u32 val, |
34f192c65 [PATCH] lightweig... |
167 |
struct compat_timespec __user *utime, u32 __user *uaddr2, |
8f17d3a50 [PATCH] lightweig... |
168 |
u32 val3) |
34f192c65 [PATCH] lightweig... |
169 |
{ |
c19384b5b Make futex_wait()... |
170 171 |
struct timespec ts; ktime_t t, *tp = NULL; |
34f192c65 [PATCH] lightweig... |
172 |
int val2 = 0; |
f0ede66fc fix compat futex ... |
173 |
int cmd = op & FUTEX_CMD_MASK; |
34f192c65 [PATCH] lightweig... |
174 |
|
cd689985c futex: Add bitset... |
175 176 |
if (utime && (cmd == FUTEX_WAIT || cmd == FUTEX_LOCK_PI || cmd == FUTEX_WAIT_BITSET)) { |
c19384b5b Make futex_wait()... |
177 |
if (get_compat_timespec(&ts, utime)) |
34f192c65 [PATCH] lightweig... |
178 |
return -EFAULT; |
c19384b5b Make futex_wait()... |
179 |
if (!timespec_valid(&ts)) |
9741ef964 [PATCH] futex: ch... |
180 |
return -EINVAL; |
c19384b5b Make futex_wait()... |
181 182 |
t = timespec_to_ktime(ts); |
f0ede66fc fix compat futex ... |
183 |
if (cmd == FUTEX_WAIT) |
5a7780e72 hrtimer: check re... |
184 |
t = ktime_add_safe(ktime_get(), t); |
c19384b5b Make futex_wait()... |
185 |
tp = &t; |
34f192c65 [PATCH] lightweig... |
186 |
} |
bd197234b Revert "futex_req... |
187 |
if (cmd == FUTEX_REQUEUE || cmd == FUTEX_CMP_REQUEUE) |
34f192c65 [PATCH] lightweig... |
188 |
val2 = (int) (unsigned long) utime; |
c19384b5b Make futex_wait()... |
189 |
return do_futex(uaddr, op, val, tp, uaddr2, val2, val3); |
34f192c65 [PATCH] lightweig... |
190 |
} |