linux/kernel
Linus Torvalds f358166a94 ptrace_attach: fix possible deadlock schenario with irqs
Eric Biederman points out that we can't take the task_lock while holding
tasklist_lock for writing, because another CPU that holds the task lock
might take an interrupt that then tries to take tasklist_lock for writing.

Which would be a nasty deadlock, with one CPU spinning forever in an
interrupt handler (although admittedly you need to really work at
triggering it ;)

Since the ptrace_attach() code is special and very unusual, just make it
be extra careful, and use trylock+repeat to avoid the possible deadlock.

Cc: Oleg Nesterov <oleg@tv-sign.ru>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Roland McGrath <roland@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-05-11 11:08:49 -07:00
..
irq [PATCH] request_irq(): remove warnings from irq probing 2006-04-28 08:33:46 -07:00
power [PATCH] off-by-1 in kernel/power/main.c 2006-04-28 08:33:46 -07:00
.gitignore gitignore: ignore more generated files 2006-01-03 11:35:26 +01:00
Kconfig.hz [PATCH] i386: Selectable Frequency of the Timer Interrupt 2005-06-23 09:45:10 -07:00
Kconfig.preempt [PATCH] sched: voluntary kernel preemption 2005-06-25 16:24:45 -07:00
Makefile [PATCH] lightweight robust futexes: compat 2006-03-27 08:44:49 -08:00
acct.c [PATCH] Fix pacct bug in multithreading case. 2006-03-31 12:18:54 -08:00
audit.c [PATCH] More user space subject labels 2006-05-01 06:10:01 -04:00
audit.h [PATCH] support for context based audit filtering, part 2 2006-05-01 06:09:36 -04:00
auditfilter.c [PATCH] More user space subject labels 2006-05-01 06:10:01 -04:00
auditsc.c [PATCH] Audit Filter Performance 2006-05-01 06:10:07 -04:00
capability.c [PATCH] refactor capable() to one implementation, add __capable() helper 2006-03-25 08:22:56 -08:00
compat.c [PATCH] lightweight robust futexes: compat 2006-03-27 08:44:49 -08:00
configs.c update the email address of Randy Dunlap 2006-01-03 13:37:51 +01:00
cpu.c [PATCH] Notifier chain update: API changes 2006-03-27 08:44:50 -08:00
cpuset.c [PATCH] cpuset: memory migration interaction fix 2006-03-31 12:18:55 -08:00
dma.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
exec_domain.c [PATCH] Fix module refcount leak in __set_personality() 2006-03-24 07:33:30 -08:00
exit.c [PATCH] move call of audit_free() into do_exit() 2006-05-01 06:06:13 -04:00
extable.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
fork.c [PATCH] move call of audit_free() into do_exit() 2006-05-01 06:06:13 -04:00
futex.c [PATCH] futex: check and validate timevals 2006-03-31 12:18:59 -08:00
futex_compat.c [PATCH] futex: check and validate timevals 2006-03-31 12:18:59 -08:00
hrtimer.c [PATCH] Remove __devinit and __cpuinit from notifier_call definitions 2006-04-26 08:30:03 -07:00
intermodule.c [PATCH] missing license tag in intermodule 2006-02-05 11:06:52 -08:00
itimer.c [PATCH] hrtimers: remove data field 2006-03-26 08:57:03 -08:00
kallsyms.c [PATCH] fix missing includes 2005-10-30 17:37:32 -08:00
kexec.c [PATCH] move capable() to capability.h 2006-01-11 18:42:13 -08:00
kfifo.c [PATCH] gfp flags annotations - part 1 2005-10-08 15:00:57 -07:00
kmod.c [PATCH] wait_for_helper: trivial style cleanup 2006-03-28 18:36:41 -08:00
kprobes.c [PATCH] kprobes: NULL out non-relevant fields in struct kretprobe 2006-04-20 07:54:03 -07:00
ksysfs.c [PATCH] fix build error if CONFIG_SYSFS=n 2006-03-24 07:33:31 -08:00
kthread.c [PATCH] find_task_by_pid() needs tasklist_lock 2006-03-25 08:22:57 -08:00
module.c [PATCH] modules: permit Dual-MIT/GPL licenses 2006-03-31 12:18:56 -08:00
mutex-debug.c [PATCH] fix/simplify mutex debugging code 2006-01-11 08:14:16 -08:00
mutex-debug.h [PATCH] mutex subsystem, debugging code 2006-01-09 15:59:20 -08:00
mutex.c [PATCH] mutex: trivial whitespace cleanups 2006-01-10 14:27:59 -08:00
mutex.h [PATCH] mutex subsystem, core 2006-01-09 15:59:19 -08:00
panic.c [PATCH] the scheduled unexport of panic_timeout 2006-04-11 06:18:40 -07:00
params.c [PATCH] Change dash2underscore() return value to char 2006-03-28 09:16:03 -08:00
pid.c [PATCH] pidhash: Refactor the pid hash table 2006-03-31 12:19:00 -08:00
posix-cpu-timers.c [PATCH] hrtimer: switch clock_nanosleep to hrtimer nanosleep API 2006-01-10 08:01:38 -08:00
posix-timers.c [PATCH] hrtimers: remove data field 2006-03-26 08:57:03 -08:00
printk.c BUG_ON() Conversion in kernel/printk.c 2006-04-01 01:21:17 +02:00
profile.c [PATCH] Remove __devinit and __cpuinit from notifier_call definitions 2006-04-26 08:30:03 -07:00
ptrace.c ptrace_attach: fix possible deadlock schenario with irqs 2006-05-11 11:08:49 -07:00
rcupdate.c [PATCH] Remove __devinit and __cpuinit from notifier_call definitions 2006-04-26 08:30:03 -07:00
rcutorture.c [PATCH] for_each_possible_cpu: fixes for generic part 2006-03-28 09:16:05 -08:00
relay.c [PATCH] relay: consolidate sendfile() and read() code 2006-03-23 19:58:45 +01:00
resource.c [PATCH] kernel/resource.c: __check_region(): remove pointless __deprecated 2006-01-10 08:02:02 -08:00
sched.c [PATCH] Remove __devinitdata from notifier block definitions 2006-04-26 08:27:50 -07:00
seccomp.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
signal.c [PATCH] fix non-leader exec under ptrace 2006-04-14 08:59:13 -07:00
softirq.c [PATCH] Remove __devinit and __cpuinit from notifier_call definitions 2006-04-26 08:30:03 -07:00
softlockup.c [PATCH] Remove __devinit and __cpuinit from notifier_call definitions 2006-04-26 08:30:03 -07:00
spinlock.c [PATCH] BUILD_LOCK_OPS: cleanup preempt_disable() usage 2006-03-23 07:38:16 -08:00
stop_machine.c [PATCH] Remove set_fs() in stop_machine() 2006-01-10 08:01:25 -08:00
sys.c [PATCH] Make setsid() more robust 2006-03-31 12:18:59 -08:00
sys_ni.c [PATCH] frv: define MMU mode specific syscalls as 'cond_syscall' and clean up unneeded macros 2006-04-11 06:18:33 -07:00
sysctl.c [PATCH] Range checking in do_proc_dointvec_(userhz_)jiffies_conv 2006-03-24 07:33:20 -08:00
time.c Fix comments: s/granuality/granularity/ 2006-04-01 01:41:22 +02:00
timer.c [PATCH] Remove __devinit and __cpuinit from notifier_call definitions 2006-04-26 08:30:03 -07:00
uid16.c [PATCH] Add more prevent_tail_call() 2006-04-19 16:27:18 -07:00
user.c [PATCH] free_uid() locking improvement 2006-03-24 07:33:20 -08:00
wait.c Linux-2.6.12-rc2 2005-04-16 15:20:36 -07:00
workqueue.c [PATCH] Remove __devinit and __cpuinit from notifier_call definitions 2006-04-26 08:30:03 -07:00