Subject: [merged] ptrace-powerpc-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch removed from -mm tree To: oleg@xxxxxxxxxx,benh@xxxxxxxxxxxxxxxxxxx,fweisbec@xxxxxxxxx,jan.kratochvil@xxxxxxxxxx,lethal@xxxxxxxxxxxx,linux@xxxxxxxxxxxxxxxx,mikey@xxxxxxxxxxx,mingo@xxxxxxxxxx,paulus@xxxxxxxxx,prasad@xxxxxxxxxxxxxxxxxx,will.deacon@xxxxxxx,mm-commits@xxxxxxxxxxxxxxx From: akpm@xxxxxxxxxxxxxxxxxxxx Date: Tue, 09 Jul 2013 16:21:05 -0700 The patch titled Subject: ptrace/powerpc: revert "hw_breakpoints: Fix racy access to ptrace breakpoints" has been removed from the -mm tree. Its filename was ptrace-powerpc-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints.patch This patch was dropped because it was merged into mainline or a subsystem tree ------------------------------------------------------ From: Oleg Nesterov <oleg@xxxxxxxxxx> Subject: ptrace/powerpc: revert "hw_breakpoints: Fix racy access to ptrace breakpoints" This reverts commit 07fa7a0a8a586 ("hw_breakpoints: Fix racy access to ptrace breakpoints") and removes ptrace_get/put_breakpoints() added by other commits. The patch was fine but we can no longer race with SIGKILL after 9899d11f ("ptrace: ensure arch_ptrace/ptrace_request can never race with SIGKILL"), the __TASK_TRACED tracee can't be woken up and ->ptrace_bps[] can't go away. Signed-off-by: Oleg Nesterov <oleg@xxxxxxxxxx> Acked-by: Michael Neuling <mikey@xxxxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Jan Kratochvil <jan.kratochvil@xxxxxxxxxx> Cc: Paul Mundt <lethal@xxxxxxxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: Prasad <prasad@xxxxxxxxxxxxxxxxxx> Cc: Russell King <linux@xxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/powerpc/kernel/ptrace.c | 30 ++++-------------------------- 1 file changed, 4 insertions(+), 26 deletions(-) diff -puN arch/powerpc/kernel/ptrace.c~ptrace-powerpc-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints arch/powerpc/kernel/ptrace.c --- a/arch/powerpc/kernel/ptrace.c~ptrace-powerpc-revert-hw_breakpoints-fix-racy-access-to-ptrace-breakpoints +++ a/arch/powerpc/kernel/ptrace.c @@ -975,16 +975,12 @@ int ptrace_set_debugreg(struct task_stru hw_brk.type = (data & HW_BRK_TYPE_DABR) | HW_BRK_TYPE_PRIV_ALL; hw_brk.len = 8; #ifdef CONFIG_HAVE_HW_BREAKPOINT - if (ptrace_get_breakpoints(task) < 0) - return -ESRCH; - bp = thread->ptrace_bps[0]; if ((!data) || !(hw_brk.type & HW_BRK_TYPE_RDWR)) { if (bp) { unregister_hw_breakpoint(bp); thread->ptrace_bps[0] = NULL; } - ptrace_put_breakpoints(task); return 0; } if (bp) { @@ -997,11 +993,9 @@ int ptrace_set_debugreg(struct task_stru ret = modify_user_hw_breakpoint(bp, &attr); if (ret) { - ptrace_put_breakpoints(task); return ret; } thread->ptrace_bps[0] = bp; - ptrace_put_breakpoints(task); thread->hw_brk = hw_brk; return 0; } @@ -1016,12 +1010,9 @@ int ptrace_set_debugreg(struct task_stru ptrace_triggered, NULL, task); if (IS_ERR(bp)) { thread->ptrace_bps[0] = NULL; - ptrace_put_breakpoints(task); return PTR_ERR(bp); } - ptrace_put_breakpoints(task); - #endif /* CONFIG_HAVE_HW_BREAKPOINT */ task->thread.hw_brk = hw_brk; #else /* CONFIG_PPC_ADV_DEBUG_REGS */ @@ -1440,26 +1431,19 @@ static long ppc_set_hwdebug(struct task_ if (bp_info->trigger_type & PPC_BREAKPOINT_TRIGGER_WRITE) brk.type |= HW_BRK_TYPE_WRITE; #ifdef CONFIG_HAVE_HW_BREAKPOINT - if (ptrace_get_breakpoints(child) < 0) - return -ESRCH; - /* * Check if the request is for 'range' breakpoints. We can * support it if range < 8 bytes. */ - if (bp_info->addr_mode == PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE) { + if (bp_info->addr_mode == PPC_BREAKPOINT_MODE_RANGE_INCLUSIVE) len = bp_info->addr2 - bp_info->addr; - } else if (bp_info->addr_mode == PPC_BREAKPOINT_MODE_EXACT) + else if (bp_info->addr_mode == PPC_BREAKPOINT_MODE_EXACT) len = 1; - else { - ptrace_put_breakpoints(child); + else return -EINVAL; - } bp = thread->ptrace_bps[0]; - if (bp) { - ptrace_put_breakpoints(child); + if (bp) return -ENOSPC; - } /* Create a new breakpoint request if one doesn't exist already */ hw_breakpoint_init(&attr); @@ -1471,11 +1455,9 @@ static long ppc_set_hwdebug(struct task_ ptrace_triggered, NULL, child); if (IS_ERR(bp)) { thread->ptrace_bps[0] = NULL; - ptrace_put_breakpoints(child); return PTR_ERR(bp); } - ptrace_put_breakpoints(child); return 1; #endif /* CONFIG_HAVE_HW_BREAKPOINT */ @@ -1519,16 +1501,12 @@ static long ppc_del_hwdebug(struct task_ return -EINVAL; #ifdef CONFIG_HAVE_HW_BREAKPOINT - if (ptrace_get_breakpoints(child) < 0) - return -ESRCH; - bp = thread->ptrace_bps[0]; if (bp) { unregister_hw_breakpoint(bp); thread->ptrace_bps[0] = NULL; } else ret = -ENOENT; - ptrace_put_breakpoints(child); return ret; #else /* CONFIG_HAVE_HW_BREAKPOINT */ if (child->thread.hw_brk.address == 0) _ Patches currently in -mm which might be from oleg@xxxxxxxxxx are origin.patch linux-next.patch mm-mempolicy-fix-mbind_range-vma_adjust-interaction.patch include-linux-schedh-dont-use-task-pid-tgid-in-same_thread_group-has_group_leader_pid.patch lockdep-introduce-lock_acquire_exclusive-shared-helper-macros.patch lglock-update-lockdep-annotations-to-report-recursive-local-locks.patch fput-task_work_add-can-fail-if-the-caller-has-passed-exit_task_work-fix.patch fput-turn-list_head-delayed_fput_list-into-llist_head.patch llist-fix-simplify-llist_add-and-llist_add_batch.patch llist-llist_add-can-use-llist_add_batch.patch kernel-wide-fix-missing-validations-on-__get-__put-__copy_to-__copy_from_user.patch autofs4-allow-autofs-to-work-outside-the-initial-pid-namespace.patch autofs4-translate-pids-to-the-right-namespace-for-the-daemon.patch signals-eventpoll-set-saved_sigmask-at-the-start.patch move-exit_task_namespaces-outside-of-exit_notify-fix.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html