diff options
-rw-r--r-- | kernel/signal.c | 71 |
1 files changed, 25 insertions, 46 deletions
diff --git a/kernel/signal.c b/kernel/signal.c index 8d6e64dfa5c6..1d905ec74bde 100644 --- a/kernel/signal.c +++ b/kernel/signal.c | |||
@@ -2283,26 +2283,13 @@ sys_kill(int pid, int sig) | |||
2283 | return kill_something_info(sig, &info, pid); | 2283 | return kill_something_info(sig, &info, pid); |
2284 | } | 2284 | } |
2285 | 2285 | ||
2286 | /** | 2286 | static int do_tkill(int tgid, int pid, int sig) |
2287 | * sys_tgkill - send signal to one specific thread | ||
2288 | * @tgid: the thread group ID of the thread | ||
2289 | * @pid: the PID of the thread | ||
2290 | * @sig: signal to be sent | ||
2291 | * | ||
2292 | * This syscall also checks the tgid and returns -ESRCH even if the PID | ||
2293 | * exists but it's not belonging to the target process anymore. This | ||
2294 | * method solves the problem of threads exiting and PIDs getting reused. | ||
2295 | */ | ||
2296 | asmlinkage long sys_tgkill(int tgid, int pid, int sig) | ||
2297 | { | 2287 | { |
2298 | struct siginfo info; | ||
2299 | int error; | 2288 | int error; |
2289 | struct siginfo info; | ||
2300 | struct task_struct *p; | 2290 | struct task_struct *p; |
2301 | 2291 | ||
2302 | /* This is only valid for single tasks */ | 2292 | error = -ESRCH; |
2303 | if (pid <= 0 || tgid <= 0) | ||
2304 | return -EINVAL; | ||
2305 | |||
2306 | info.si_signo = sig; | 2293 | info.si_signo = sig; |
2307 | info.si_errno = 0; | 2294 | info.si_errno = 0; |
2308 | info.si_code = SI_TKILL; | 2295 | info.si_code = SI_TKILL; |
@@ -2311,8 +2298,7 @@ asmlinkage long sys_tgkill(int tgid, int pid, int sig) | |||
2311 | 2298 | ||
2312 | read_lock(&tasklist_lock); | 2299 | read_lock(&tasklist_lock); |
2313 | p = find_task_by_pid(pid); | 2300 | p = find_task_by_pid(pid); |
2314 | error = -ESRCH; | 2301 | if (p && (tgid <= 0 || p->tgid == tgid)) { |
2315 | if (p && (p->tgid == tgid)) { | ||
2316 | error = check_kill_permission(sig, &info, p); | 2302 | error = check_kill_permission(sig, &info, p); |
2317 | /* | 2303 | /* |
2318 | * The null signal is a permissions and process existence | 2304 | * The null signal is a permissions and process existence |
@@ -2326,47 +2312,40 @@ asmlinkage long sys_tgkill(int tgid, int pid, int sig) | |||
2326 | } | 2312 | } |
2327 | } | 2313 | } |
2328 | read_unlock(&tasklist_lock); | 2314 | read_unlock(&tasklist_lock); |
2315 | |||
2329 | return error; | 2316 | return error; |
2330 | } | 2317 | } |
2331 | 2318 | ||
2319 | /** | ||
2320 | * sys_tgkill - send signal to one specific thread | ||
2321 | * @tgid: the thread group ID of the thread | ||
2322 | * @pid: the PID of the thread | ||
2323 | * @sig: signal to be sent | ||
2324 | * | ||
2325 | * This syscall also checks the tgid and returns -ESRCH even if the PID | ||
2326 | * exists but it's not belonging to the target process anymore. This | ||
2327 | * method solves the problem of threads exiting and PIDs getting reused. | ||
2328 | */ | ||
2329 | asmlinkage long sys_tgkill(int tgid, int pid, int sig) | ||
2330 | { | ||
2331 | /* This is only valid for single tasks */ | ||
2332 | if (pid <= 0 || tgid <= 0) | ||
2333 | return -EINVAL; | ||
2334 | |||
2335 | return do_tkill(tgid, pid, sig); | ||
2336 | } | ||
2337 | |||
2332 | /* | 2338 | /* |
2333 | * Send a signal to only one task, even if it's a CLONE_THREAD task. | 2339 | * Send a signal to only one task, even if it's a CLONE_THREAD task. |
2334 | */ | 2340 | */ |
2335 | asmlinkage long | 2341 | asmlinkage long |
2336 | sys_tkill(int pid, int sig) | 2342 | sys_tkill(int pid, int sig) |
2337 | { | 2343 | { |
2338 | struct siginfo info; | ||
2339 | int error; | ||
2340 | struct task_struct *p; | ||
2341 | |||
2342 | /* This is only valid for single tasks */ | 2344 | /* This is only valid for single tasks */ |
2343 | if (pid <= 0) | 2345 | if (pid <= 0) |
2344 | return -EINVAL; | 2346 | return -EINVAL; |
2345 | 2347 | ||
2346 | info.si_signo = sig; | 2348 | return do_tkill(0, pid, sig); |
2347 | info.si_errno = 0; | ||
2348 | info.si_code = SI_TKILL; | ||
2349 | info.si_pid = current->tgid; | ||
2350 | info.si_uid = current->uid; | ||
2351 | |||
2352 | read_lock(&tasklist_lock); | ||
2353 | p = find_task_by_pid(pid); | ||
2354 | error = -ESRCH; | ||
2355 | if (p) { | ||
2356 | error = check_kill_permission(sig, &info, p); | ||
2357 | /* | ||
2358 | * The null signal is a permissions and process existence | ||
2359 | * probe. No signal is actually delivered. | ||
2360 | */ | ||
2361 | if (!error && sig && p->sighand) { | ||
2362 | spin_lock_irq(&p->sighand->siglock); | ||
2363 | handle_stop_signal(sig, p); | ||
2364 | error = specific_send_sig_info(sig, &info, p); | ||
2365 | spin_unlock_irq(&p->sighand->siglock); | ||
2366 | } | ||
2367 | } | ||
2368 | read_unlock(&tasklist_lock); | ||
2369 | return error; | ||
2370 | } | 2349 | } |
2371 | 2350 | ||
2372 | asmlinkage long | 2351 | asmlinkage long |