strace: fix potential deadlock during cleanup
(cherry picked from commit fb283e98eb9df90d0a98bf4c8053ea3ffa88c592)
This commit is contained in:
wangxiao65
openeuler-sync-bot
parent
2548cb66e1
commit
c2f4a25c7a
67
backport-0001-Fix-the-type-of-tcbtab-iterators.patch
Normal file
67
backport-0001-Fix-the-type-of-tcbtab-iterators.patch
Normal file
@ -0,0 +1,67 @@
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From 9ccfe110343369ea8986fb8781a679373b9b8892 Mon Sep 17 00:00:00 2001
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From: "Dmitry V. Levin" <ldv@strace.io>
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Date: Thu, 23 Nov 2023 08:00:00 +0000
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Subject: [PATCH] Fix the type of tcbtab iterators
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* src/strace.c (alloctcb, startup_attach, init, pid2tcb, cleanup):
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Change the type of tcbtab iterators from unsigned int to size_t so that
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they match the type of tcbtabsize.
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Reference: https://github.com/strace/strace/commit/9ccfe110343369ea8986fb8781a679373b9b8892
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Conflict: NA
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---
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src/strace.c | 10 +++++-----
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1 file changed, 5 insertions(+), 5 deletions(-)
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diff --git a/src/strace.c b/src/strace.c
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index 6f808996e..d3fa44f30 100644
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--- a/src/strace.c
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+++ b/src/strace.c
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@@ -1033,7 +1033,7 @@ alloctcb(int pid)
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if (nprocs == tcbtabsize)
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expand_tcbtab();
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- for (unsigned int i = 0; i < tcbtabsize; ++i) {
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+ for (size_t i = 0; i < tcbtabsize; ++i) {
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struct tcb *tcp = tcbtab[i];
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if (!tcp->pid) {
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memset(tcp, 0, sizeof(*tcp));
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@@ -1447,7 +1447,7 @@ startup_attach(void)
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debug_msg("new tracer pid is %d", strace_tracer_pid);
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}
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- for (unsigned int tcbi = 0; tcbi < tcbtabsize; ++tcbi) {
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+ for (size_t tcbi = 0; tcbi < tcbtabsize; ++tcbi) {
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tcp = tcbtab[tcbi];
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if (!tcp->pid)
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@@ -2761,7 +2761,7 @@ init(int argc, char *argv[])
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* of tcbs are not filled though tcbs are initialized.
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* We must fill the fields here.
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*/
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- for (unsigned int i = 0; i < tcbtabsize; ++i) {
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+ for (size_t i = 0; i < tcbtabsize; ++i) {
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struct tcb *tcp = tcbtab[i];
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if (tcp->comm[0] == 0)
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maybe_load_task_comm(tcp);
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@@ -3090,7 +3090,7 @@ pid2tcb(const int pid)
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if (tcp && tcp->pid == pid)
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return tcp;
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- for (unsigned int i = 0; i < tcbtabsize; ++i) {
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+ for (size_t i = 0; i < tcbtabsize; ++i) {
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tcp = tcbtab[i];
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if (tcp->pid == pid)
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return *ptcp = tcp;
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@@ -3108,7 +3108,7 @@ cleanup(int fatal_sig)
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if (!fatal_sig)
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fatal_sig = SIGTERM;
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- for (unsigned int i = 0; i < tcbtabsize; ++i) {
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+ for (size_t i = 0; i < tcbtabsize; ++i) {
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struct tcb *tcp = tcbtab[i];
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if (!tcp->pid)
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continue;
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--
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2.33.0
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@ -0,0 +1,90 @@
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From 651640fd5faf0e24d9cd88c596854c108f732329 Mon Sep 17 00:00:00 2001
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From: "Dmitry V. Levin" <ldv@strace.io>
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Date: Fri, 24 Nov 2023 08:00:00 +0000
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Subject: [PATCH] Move print_debug_info() definition before cleanup()
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* src/strace.c (print_debug_info): Move before cleanup().
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Reference: https://github.com/strace/strace/commit/651640fd5faf0e24d9cd88c596854c108f732329
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Conflict: NA
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---
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src/strace.c | 56 ++++++++++++++++++++++++++--------------------------
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1 file changed, 28 insertions(+), 28 deletions(-)
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diff --git a/src/strace.c b/src/strace.c
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index d3fa44f30..28f5b4368 100644
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--- a/src/strace.c
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+++ b/src/strace.c
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@@ -3099,34 +3099,6 @@ pid2tcb(const int pid)
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return NULL;
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}
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-static void
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-cleanup(int fatal_sig)
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-{
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- if (ptrace_setoptions & PTRACE_O_EXITKILL)
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- return;
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-
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- if (!fatal_sig)
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- fatal_sig = SIGTERM;
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-
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- for (size_t i = 0; i < tcbtabsize; ++i) {
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- struct tcb *tcp = tcbtab[i];
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- if (!tcp->pid)
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- continue;
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- debug_func_msg("looking at pid %u", tcp->pid);
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- if (tcp->pid == strace_child) {
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- kill(tcp->pid, SIGCONT);
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- kill(tcp->pid, fatal_sig);
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- }
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- detach(tcp);
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- }
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-}
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-
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-static void
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-interrupt(int sig)
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-{
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- interrupted = sig;
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-}
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-
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static void
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print_debug_info(const int pid, int status)
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{
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@@ -3166,6 +3138,34 @@ print_debug_info(const int pid, int status)
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error_msg("[wait(0x%06x) = %u] %s%s", status, pid, buf, evbuf);
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}
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+static void
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+cleanup(int fatal_sig)
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+{
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+ if (ptrace_setoptions & PTRACE_O_EXITKILL)
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+ return;
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+
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+ if (!fatal_sig)
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+ fatal_sig = SIGTERM;
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+
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+ for (size_t i = 0; i < tcbtabsize; ++i) {
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+ struct tcb *tcp = tcbtab[i];
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+ if (!tcp->pid)
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+ continue;
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+ debug_func_msg("looking at pid %u", tcp->pid);
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+ if (tcp->pid == strace_child) {
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+ kill(tcp->pid, SIGCONT);
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+ kill(tcp->pid, fatal_sig);
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+ }
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+ detach(tcp);
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+ }
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+}
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+
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+static void
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+interrupt(int sig)
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+{
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+ interrupted = sig;
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+}
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+
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static struct tcb *
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maybe_allocate_tcb(const int pid, int status)
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{
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--
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2.33.0
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51
backport-0003-Factor-out-droptcb_verbose-from-detach.patch
Normal file
51
backport-0003-Factor-out-droptcb_verbose-from-detach.patch
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@ -0,0 +1,51 @@
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From 83a2af722ce2c2b38f3d6d9f4114015521449a2a Mon Sep 17 00:00:00 2001
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From: "Dmitry V. Levin" <ldv@strace.io>
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Date: Sat, 25 Nov 2023 08:00:00 +0000
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Subject: [PATCH] Factor out droptcb_verbose() from detach()
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* src/strace.c (droptcb_verbose): New function.
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(detach): Use it instead of droptcb.
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Reference: https://github.com/strace/strace/commit/83a2af722ce2c2b38f3d6d9f4114015521449a2a
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Conflict: NA
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---
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src/strace.c | 16 +++++++++++-----
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1 file changed, 11 insertions(+), 5 deletions(-)
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diff --git a/src/strace.c b/src/strace.c
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index 28f5b4368..351842792 100644
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--- a/src/strace.c
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+++ b/src/strace.c
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@@ -1148,6 +1148,16 @@ droptcb(struct tcb *tcp)
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memset(tcp, 0, sizeof(*tcp));
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}
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+static void
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+droptcb_verbose(struct tcb *tcp)
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+{
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+ if (!is_number_in_set(QUIET_ATTACH, quiet_set)
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+ && (tcp->flags & TCB_ATTACHED))
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+ error_msg("Process %u detached", tcp->pid);
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+
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+ droptcb(tcp);
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+}
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+
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/* Detach traced process.
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* Never call DETACH twice on the same process as both unattached and
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* attached-unstopped processes give the same ESRCH. For unattached process we
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@@ -1302,11 +1312,7 @@ detach(struct tcb *tcp)
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}
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drop:
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- if (!is_number_in_set(QUIET_ATTACH, quiet_set)
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- && (tcp->flags & TCB_ATTACHED))
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- error_msg("Process %u detached", tcp->pid);
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-
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- droptcb(tcp);
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+ droptcb_verbose(tcp);
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}
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static void
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--
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2.33.0
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127
backport-0004-Factor-out-interrupt_or_stop-from-detach.patch
Normal file
127
backport-0004-Factor-out-interrupt_or_stop-from-detach.patch
Normal file
@ -0,0 +1,127 @@
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From 4c4c339585b523167e336d9b379fe4c00dc94dca Mon Sep 17 00:00:00 2001
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From: "Dmitry V. Levin" <ldv@strace.io>
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Date: Sun, 26 Nov 2023 08:00:00 +0000
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Subject: [PATCH] Factor out interrupt_or_stop() from detach()
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* src/strace.c (interrupt_or_stop): New function.
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(detach): Use it.
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Reference: https://github.com/strace/strace/commit/4c4c339585b523167e336d9b379fe4c00dc94dca
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Conflict: NA
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---
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src/strace.c | 49 ++++++++++++++++++++++++++++---------------------
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1 file changed, 28 insertions(+), 21 deletions(-)
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diff --git a/src/strace.c b/src/strace.c
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index 351842792..385cbaa72 100644
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--- a/src/strace.c
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+++ b/src/strace.c
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@@ -1158,17 +1158,10 @@ droptcb_verbose(struct tcb *tcp)
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droptcb(tcp);
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}
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-/* Detach traced process.
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- * Never call DETACH twice on the same process as both unattached and
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- * attached-unstopped processes give the same ESRCH. For unattached process we
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- * would SIGSTOP it and wait for its SIGSTOP notification forever.
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- */
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-static void
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-detach(struct tcb *tcp)
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+/* Returns true when the tracee has to be waited for. */
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+static bool
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+interrupt_or_stop(struct tcb *tcp)
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{
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- int error;
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- int status;
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-
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/*
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* Linux wrongly insists the child be stopped
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* before detaching. Arghh. We go through hoops
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@@ -1176,24 +1169,24 @@ detach(struct tcb *tcp)
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*/
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if (!(tcp->flags & TCB_ATTACHED))
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- goto drop;
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+ return false;
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/* We attached but possibly didn't see the expected SIGSTOP.
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* We must catch exactly one as otherwise the detached process
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* would be left stopped (process state T).
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*/
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if (tcp->flags & TCB_IGNORE_ONE_SIGSTOP)
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- goto wait_loop;
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+ return true;
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- error = ptrace(PTRACE_DETACH, tcp->pid, 0, 0);
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+ int error = ptrace(PTRACE_DETACH, tcp->pid, 0, 0);
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|
if (!error) {
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/* On a clear day, you can see forever. */
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- goto drop;
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+ return false;
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}
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if (errno != ESRCH) {
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/* Shouldn't happen. */
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perror_func_msg("ptrace(PTRACE_DETACH,%u)", tcp->pid);
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- goto drop;
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+ return false;
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}
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/* ESRCH: process is either not stopped or doesn't exist. */
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if (my_tkill(tcp->pid, 0) < 0) {
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@@ -1201,7 +1194,7 @@ detach(struct tcb *tcp)
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/* Shouldn't happen. */
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perror_func_msg("tkill(%u,0)", tcp->pid);
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/* else: process doesn't exist. */
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- goto drop;
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|
+ return false;
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|
}
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|
/* Process is not stopped, need to stop it. */
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|
if (use_seize) {
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|
@@ -1213,26 +1206,40 @@ detach(struct tcb *tcp)
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|
*/
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|
error = ptrace(PTRACE_INTERRUPT, tcp->pid, 0, 0);
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|
if (!error)
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|
- goto wait_loop;
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|
+ return true;
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|
if (errno != ESRCH)
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|
perror_func_msg("ptrace(PTRACE_INTERRUPT,%u)", tcp->pid);
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|
} else {
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|
error = my_tkill(tcp->pid, SIGSTOP);
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|
if (!error)
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|
- goto wait_loop;
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|
+ return true;
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|
if (errno != ESRCH)
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|
perror_func_msg("tkill(%u,SIGSTOP)", tcp->pid);
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|
}
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|
+
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|
/* Either process doesn't exist, or some weird error. */
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|
- goto drop;
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|
+ return false;
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|
+}
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|
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|
- wait_loop:
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|
- /* We end up here in three cases:
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|
+/* Detach traced process.
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|
+ * Never call DETACH twice on the same process as both unattached and
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|
+ * attached-unstopped processes give the same ESRCH. For unattached process we
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|
+ * would SIGSTOP it and wait for its SIGSTOP notification forever.
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|
+ */
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|
+static void
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|
+detach(struct tcb *tcp)
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|
+{
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|
+ if (!interrupt_or_stop(tcp))
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|
+ goto drop;
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|
+
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|
+ /*
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|
+ * We end up here in three cases:
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|
* 1. We sent PTRACE_INTERRUPT (use_seize case)
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|
* 2. We sent SIGSTOP (!use_seize)
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* 3. Attach SIGSTOP was already pending (TCB_IGNORE_ONE_SIGSTOP set)
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|
*/
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|
for (;;) {
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|
+ int status;
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|
unsigned int sig;
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|
if (waitpid(tcp->pid, &status, __WALL) < 0) {
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|
if (errno == EINTR)
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|
--
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|
2.33.0
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|
|
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@ -0,0 +1,179 @@
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|
From d275fc0312255ddffa878b70da34d945b4fd8212 Mon Sep 17 00:00:00 2001
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|
From: "Dmitry V. Levin" <ldv@strace.io>
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|
Date: Mon, 27 Nov 2023 08:00:00 +0000
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|
Subject: [PATCH] Factor out detach_interrupted_or_stopped() from detach()
|
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|
|
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|
* src/strace.c (detach_interrupted_or_stopped): New function.
|
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|
(detach): Use it.
|
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|
|
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|
Reference: https://github.com/strace/strace/commit/d275fc0312255ddffa878b70da34d945b4fd8212
|
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|
Conflict: NA
|
||||||
|
---
|
||||||
|
src/strace.c | 136 +++++++++++++++++++++++++++------------------------
|
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|
1 file changed, 72 insertions(+), 64 deletions(-)
|
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|
|
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|
diff --git a/src/strace.c b/src/strace.c
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|
index 385cbaa72..ef3360b95 100644
|
||||||
|
--- a/src/strace.c
|
||||||
|
+++ b/src/strace.c
|
||||||
|
@@ -1221,6 +1221,77 @@ interrupt_or_stop(struct tcb *tcp)
|
||||||
|
return false;
|
||||||
|
}
|
||||||
|
|
||||||
|
+/* Returns true if the tracee can be passed to droptcb. */
|
||||||
|
+static bool
|
||||||
|
+detach_interrupted_or_stopped(struct tcb *tcp, int status)
|
||||||
|
+{
|
||||||
|
+ if (!WIFSTOPPED(status)) {
|
||||||
|
+ /*
|
||||||
|
+ * Tracee exited or was killed by signal.
|
||||||
|
+ * We shouldn't normally reach this place:
|
||||||
|
+ * we don't want to consume exit status.
|
||||||
|
+ * Consider "strace -p PID" being ^C-ed:
|
||||||
|
+ * we want merely to detach from PID.
|
||||||
|
+ *
|
||||||
|
+ * However, we _can_ end up here if tracee
|
||||||
|
+ * was SIGKILLed.
|
||||||
|
+ */
|
||||||
|
+ return true;
|
||||||
|
+ }
|
||||||
|
+ unsigned int sig = WSTOPSIG(status);
|
||||||
|
+ debug_msg("detach wait: event:%d sig:%d",
|
||||||
|
+ (unsigned) status >> 16, sig);
|
||||||
|
+ if (use_seize) {
|
||||||
|
+ unsigned event = (unsigned)status >> 16;
|
||||||
|
+ if (event == PTRACE_EVENT_STOP /*&& sig == SIGTRAP*/) {
|
||||||
|
+ /*
|
||||||
|
+ * sig == SIGTRAP: PTRACE_INTERRUPT stop.
|
||||||
|
+ * sig == other: process was already stopped
|
||||||
|
+ * with this stopping sig (see tests/detach-stopped).
|
||||||
|
+ * Looks like re-injecting this sig is not necessary
|
||||||
|
+ * in DETACH for the tracee to remain stopped.
|
||||||
|
+ */
|
||||||
|
+ sig = 0;
|
||||||
|
+ }
|
||||||
|
+ /*
|
||||||
|
+ * PTRACE_INTERRUPT is not guaranteed to produce
|
||||||
|
+ * the above event if other ptrace-stop is pending.
|
||||||
|
+ * See tests/detach-sleeping testcase:
|
||||||
|
+ * strace got SIGINT while tracee is sleeping.
|
||||||
|
+ * We sent PTRACE_INTERRUPT.
|
||||||
|
+ * We see syscall exit, not PTRACE_INTERRUPT stop.
|
||||||
|
+ * We won't get PTRACE_INTERRUPT stop
|
||||||
|
+ * if we would CONT now. Need to DETACH.
|
||||||
|
+ */
|
||||||
|
+ if (sig == syscall_trap_sig)
|
||||||
|
+ sig = 0;
|
||||||
|
+ /* else: not sure in which case we can be here.
|
||||||
|
+ * Signal stop? Inject it while detaching.
|
||||||
|
+ */
|
||||||
|
+ ptrace_restart(PTRACE_DETACH, tcp, sig);
|
||||||
|
+ return true;
|
||||||
|
+ }
|
||||||
|
+ /* Note: this check has to be after use_seize check */
|
||||||
|
+ /* (else, in use_seize case SIGSTOP will be mistreated) */
|
||||||
|
+ if (sig == SIGSTOP) {
|
||||||
|
+ /* Detach, suppressing SIGSTOP */
|
||||||
|
+ ptrace_restart(PTRACE_DETACH, tcp, 0);
|
||||||
|
+ return true;
|
||||||
|
+ }
|
||||||
|
+ if (sig == syscall_trap_sig)
|
||||||
|
+ sig = 0;
|
||||||
|
+ /* Can't detach just yet, may need to wait for SIGSTOP */
|
||||||
|
+ int error = ptrace_restart(PTRACE_CONT, tcp, sig);
|
||||||
|
+ if (error < 0) {
|
||||||
|
+ /* Should not happen.
|
||||||
|
+ * Note: ptrace_restart returns 0 on ESRCH, so it's not it.
|
||||||
|
+ * ptrace_restart already emitted error message.
|
||||||
|
+ */
|
||||||
|
+ return true;
|
||||||
|
+ }
|
||||||
|
+ return false;
|
||||||
|
+}
|
||||||
|
+
|
||||||
|
/* Detach traced process.
|
||||||
|
* Never call DETACH twice on the same process as both unattached and
|
||||||
|
* attached-unstopped processes give the same ESRCH. For unattached process we
|
||||||
|
@@ -1240,7 +1311,6 @@ detach(struct tcb *tcp)
|
||||||
|
*/
|
||||||
|
for (;;) {
|
||||||
|
int status;
|
||||||
|
- unsigned int sig;
|
||||||
|
if (waitpid(tcp->pid, &status, __WALL) < 0) {
|
||||||
|
if (errno == EINTR)
|
||||||
|
continue;
|
||||||
|
@@ -1252,70 +1322,8 @@ detach(struct tcb *tcp)
|
||||||
|
perror_func_msg("waitpid(%u)", tcp->pid);
|
||||||
|
break;
|
||||||
|
}
|
||||||
|
- if (!WIFSTOPPED(status)) {
|
||||||
|
- /*
|
||||||
|
- * Tracee exited or was killed by signal.
|
||||||
|
- * We shouldn't normally reach this place:
|
||||||
|
- * we don't want to consume exit status.
|
||||||
|
- * Consider "strace -p PID" being ^C-ed:
|
||||||
|
- * we want merely to detach from PID.
|
||||||
|
- *
|
||||||
|
- * However, we _can_ end up here if tracee
|
||||||
|
- * was SIGKILLed.
|
||||||
|
- */
|
||||||
|
- break;
|
||||||
|
- }
|
||||||
|
- sig = WSTOPSIG(status);
|
||||||
|
- debug_msg("detach wait: event:%d sig:%d",
|
||||||
|
- (unsigned) status >> 16, sig);
|
||||||
|
- if (use_seize) {
|
||||||
|
- unsigned event = (unsigned)status >> 16;
|
||||||
|
- if (event == PTRACE_EVENT_STOP /*&& sig == SIGTRAP*/) {
|
||||||
|
- /*
|
||||||
|
- * sig == SIGTRAP: PTRACE_INTERRUPT stop.
|
||||||
|
- * sig == other: process was already stopped
|
||||||
|
- * with this stopping sig (see tests/detach-stopped).
|
||||||
|
- * Looks like re-injecting this sig is not necessary
|
||||||
|
- * in DETACH for the tracee to remain stopped.
|
||||||
|
- */
|
||||||
|
- sig = 0;
|
||||||
|
- }
|
||||||
|
- /*
|
||||||
|
- * PTRACE_INTERRUPT is not guaranteed to produce
|
||||||
|
- * the above event if other ptrace-stop is pending.
|
||||||
|
- * See tests/detach-sleeping testcase:
|
||||||
|
- * strace got SIGINT while tracee is sleeping.
|
||||||
|
- * We sent PTRACE_INTERRUPT.
|
||||||
|
- * We see syscall exit, not PTRACE_INTERRUPT stop.
|
||||||
|
- * We won't get PTRACE_INTERRUPT stop
|
||||||
|
- * if we would CONT now. Need to DETACH.
|
||||||
|
- */
|
||||||
|
- if (sig == syscall_trap_sig)
|
||||||
|
- sig = 0;
|
||||||
|
- /* else: not sure in which case we can be here.
|
||||||
|
- * Signal stop? Inject it while detaching.
|
||||||
|
- */
|
||||||
|
- ptrace_restart(PTRACE_DETACH, tcp, sig);
|
||||||
|
- break;
|
||||||
|
- }
|
||||||
|
- /* Note: this check has to be after use_seize check */
|
||||||
|
- /* (else, in use_seize case SIGSTOP will be mistreated) */
|
||||||
|
- if (sig == SIGSTOP) {
|
||||||
|
- /* Detach, suppressing SIGSTOP */
|
||||||
|
- ptrace_restart(PTRACE_DETACH, tcp, 0);
|
||||||
|
+ if (detach_interrupted_or_stopped(tcp, status))
|
||||||
|
break;
|
||||||
|
- }
|
||||||
|
- if (sig == syscall_trap_sig)
|
||||||
|
- sig = 0;
|
||||||
|
- /* Can't detach just yet, may need to wait for SIGSTOP */
|
||||||
|
- error = ptrace_restart(PTRACE_CONT, tcp, sig);
|
||||||
|
- if (error < 0) {
|
||||||
|
- /* Should not happen.
|
||||||
|
- * Note: ptrace_restart returns 0 on ESRCH, so it's not it.
|
||||||
|
- * ptrace_restart already emitted error message.
|
||||||
|
- */
|
||||||
|
- break;
|
||||||
|
- }
|
||||||
|
}
|
||||||
|
|
||||||
|
drop:
|
||||||
|
--
|
||||||
|
2.33.0
|
||||||
|
|
||||||
118
backport-0006-strace-fix-potential-deadlock-during-cleanup.patch
Normal file
118
backport-0006-strace-fix-potential-deadlock-during-cleanup.patch
Normal file
@ -0,0 +1,118 @@
|
|||||||
|
From 3cfa90b54367168cc1e473af004675f12816e955 Mon Sep 17 00:00:00 2001
|
||||||
|
From: donghaobo <donghaobo@kuaishou.com>
|
||||||
|
Date: Fri, 17 Nov 2023 13:55:22 +0800
|
||||||
|
Subject: [PATCH] strace: fix potential deadlock during cleanup
|
||||||
|
|
||||||
|
strace -f can potentially deadlock during cleanup if the tracee
|
||||||
|
is using vfork or CLONE_VFORK to spawn threads.
|
||||||
|
|
||||||
|
On linux, calling vfork will cause the calling thread to 'D' state
|
||||||
|
until the child process calls execve or exit. Therefore, strace
|
||||||
|
should detach the child process first, otherwise it can wait
|
||||||
|
indefinitely for the calling thread in 'D' state.
|
||||||
|
|
||||||
|
Reproducer:
|
||||||
|
|
||||||
|
/*
|
||||||
|
* Start tracing with strace -f,
|
||||||
|
* then press Ctrl-C within 9 seconds to interrupt.
|
||||||
|
*/
|
||||||
|
#include <stdlib.h>
|
||||||
|
#include <unistd.h>
|
||||||
|
#include <sys/wait.h>
|
||||||
|
int main(void)
|
||||||
|
{
|
||||||
|
pid_t pid = vfork();
|
||||||
|
if (pid < 0)
|
||||||
|
return 1;
|
||||||
|
if (pid) {
|
||||||
|
int status;
|
||||||
|
waitpid(pid, &status, 0);
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
sleep(9);
|
||||||
|
_exit(0);
|
||||||
|
}
|
||||||
|
|
||||||
|
* src/strace.c (cleanup): Do not call detach() for each tracee
|
||||||
|
one by one as it can deadlock, instead call interrupt_or_stop()
|
||||||
|
for each tracee and after that enter a wait loop calling
|
||||||
|
detach_interrupted_or_stopped() for each tracee as soon as
|
||||||
|
they become ready.
|
||||||
|
* NEWS: Mention this fix.
|
||||||
|
|
||||||
|
Co-authored-by: Dmitry V. Levin <ldv@strace.io>
|
||||||
|
|
||||||
|
Reference: https://github.com/strace/strace/commit/3cfa90b54367168cc1e473af004675f12816e955
|
||||||
|
Conflict: Remove NEWS
|
||||||
|
---
|
||||||
|
NEWS | 2 ++
|
||||||
|
src/strace.c | 45 ++++++++++++++++++++++++++++++++++++++++++++-
|
||||||
|
2 files changed, 46 insertions(+), 1 deletion(-)
|
||||||
|
|
||||||
|
diff --git a/src/strace.c b/src/strace.c
|
||||||
|
index ef3360b95..04b3c1dfe 100644
|
||||||
|
--- a/src/strace.c
|
||||||
|
+++ b/src/strace.c
|
||||||
|
@@ -3168,6 +3168,8 @@ cleanup(int fatal_sig)
|
||||||
|
if (!fatal_sig)
|
||||||
|
fatal_sig = SIGTERM;
|
||||||
|
|
||||||
|
+ size_t num_to_wait = 0;
|
||||||
|
+
|
||||||
|
for (size_t i = 0; i < tcbtabsize; ++i) {
|
||||||
|
struct tcb *tcp = tcbtab[i];
|
||||||
|
if (!tcp->pid)
|
||||||
|
@@ -3177,7 +3179,48 @@ cleanup(int fatal_sig)
|
||||||
|
kill(tcp->pid, SIGCONT);
|
||||||
|
kill(tcp->pid, fatal_sig);
|
||||||
|
}
|
||||||
|
- detach(tcp);
|
||||||
|
+ if (interrupt_or_stop(tcp))
|
||||||
|
+ ++num_to_wait;
|
||||||
|
+ else
|
||||||
|
+ droptcb_verbose(tcp);
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ while (num_to_wait) {
|
||||||
|
+ int status;
|
||||||
|
+ pid_t pid = waitpid(-1, &status, __WALL);
|
||||||
|
+
|
||||||
|
+ if (pid < 0) {
|
||||||
|
+ if (errno == EINTR)
|
||||||
|
+ continue;
|
||||||
|
+ /* ECHILD is not expected */
|
||||||
|
+ perror_func_msg("waitpid(-1, __WALL)");
|
||||||
|
+ break;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ if (pid == popen_pid) {
|
||||||
|
+ if (!WIFSTOPPED(status))
|
||||||
|
+ popen_pid = 0;
|
||||||
|
+ continue;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ if (debug_flag)
|
||||||
|
+ print_debug_info(pid, status);
|
||||||
|
+
|
||||||
|
+ struct tcb *tcp = pid2tcb(pid);
|
||||||
|
+ if (!tcp) {
|
||||||
|
+ if (!is_number_in_set(QUIET_EXIT, quiet_set)) {
|
||||||
|
+ /*
|
||||||
|
+ * This can happen if we inherited an unknown child.
|
||||||
|
+ */
|
||||||
|
+ error_msg("Exit of unknown pid %u ignored", pid);
|
||||||
|
+ }
|
||||||
|
+ continue;
|
||||||
|
+ }
|
||||||
|
+
|
||||||
|
+ if (detach_interrupted_or_stopped(tcp, status)) {
|
||||||
|
+ droptcb_verbose(tcp);
|
||||||
|
+ --num_to_wait;
|
||||||
|
+ }
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
--
|
||||||
|
2.33.0
|
||||||
|
|
||||||
12
strace.spec
12
strace.spec
@ -1,7 +1,7 @@
|
|||||||
Summary: Tracks and displays system calls associated with a running process
|
Summary: Tracks and displays system calls associated with a running process
|
||||||
Name: strace
|
Name: strace
|
||||||
Version: 6.6
|
Version: 6.6
|
||||||
Release: 2
|
Release: 3
|
||||||
# The test suite is GPLv2+, all the rest is LGPLv2.1+.
|
# The test suite is GPLv2+, all the rest is LGPLv2.1+.
|
||||||
License: LGPL-2.1+ and GPL-2.0+
|
License: LGPL-2.1+ and GPL-2.0+
|
||||||
# Some distros require Group tag to be present,
|
# Some distros require Group tag to be present,
|
||||||
@ -20,6 +20,13 @@ BuildRequires: pkgconfig(bluez)
|
|||||||
# Install binutils-devel to enable symbol demangling.
|
# Install binutils-devel to enable symbol demangling.
|
||||||
BuildRequires: elfutils-devel binutils-devel
|
BuildRequires: elfutils-devel binutils-devel
|
||||||
|
|
||||||
|
Patch0001: backport-0001-Fix-the-type-of-tcbtab-iterators.patch
|
||||||
|
Patch0002: backport-0002-Move-print_debug_info-definition-before-cleanup.patch
|
||||||
|
Patch0003: backport-0003-Factor-out-droptcb_verbose-from-detach.patch
|
||||||
|
Patch0004: backport-0004-Factor-out-interrupt_or_stop-from-detach.patch
|
||||||
|
Patch0005: backport-0005-Factor-out-detach_interrupted_or_stopped-from-detach.patch
|
||||||
|
Patch0006: backport-0006-strace-fix-potential-deadlock-during-cleanup.patch
|
||||||
|
|
||||||
# OBS compatibility
|
# OBS compatibility
|
||||||
%{?!buildroot:BuildRoot: %_tmppath/buildroot-%name-%version-%release}
|
%{?!buildroot:BuildRoot: %_tmppath/buildroot-%name-%version-%release}
|
||||||
%define maybe_use_defattr %{?suse_version:%%defattr(-,root,root)}
|
%define maybe_use_defattr %{?suse_version:%%defattr(-,root,root)}
|
||||||
@ -100,6 +107,9 @@ wait
|
|||||||
%{_mandir}/man1/*
|
%{_mandir}/man1/*
|
||||||
|
|
||||||
%changelog
|
%changelog
|
||||||
|
* Fri Dec 27 2024 wangxiao <wangxiao184@h-partners.com> - 6.6-3
|
||||||
|
- strace: fix potential deadlock during cleanup
|
||||||
|
|
||||||
* Wed Feb 28 2024 liuchao <liuchao173@huawei.com> - 6.6-2
|
* Wed Feb 28 2024 liuchao <liuchao173@huawei.com> - 6.6-2
|
||||||
- remove redundant judgments
|
- remove redundant judgments
|
||||||
|
|
||||||
|
|||||||
Loading…
x
Reference in New Issue
Block a user