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| author | Bradley Morgan <include@grrlz.net> | 2026-06-22 20:25:08 +0000 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2026-09-07 17:18:24 +0200 |
| commit | 03c8761e75d1619906bb503686f9cc1dfc6a67f4 (patch) | |
| tree | d40b28bc6b9d3cb3bd9958ef4390c91cfb2a13d4 | |
| parent | 71f7da08709fcc349da1f8e7aacbcb048eeabdad (diff) | |
| download | linux-03c8761e75d1619906bb503686f9cc1dfc6a67f4.tar.gz linux-03c8761e75d1619906bb503686f9cc1dfc6a67f4.zip | |
signal: avoid shared siginfo namespace rewrites
commit d19cdc167e696714509e87d3f7ae765b6e164589 upstream.
send_signal_locked() rewrites sender ids for the target namespace. Group
sends reuse the same siginfo, so one recipient can affect the next.
Copy the siginfo before changing it.
Link: https://lore.kernel.org/86a8857d58d43ee26a8b365b837fd24830343494.1782159692.git.include@grrlz.net
Fixes: 7a0cf094944e ("signal: Correct namespace fixups of si_pid and si_uid")
Signed-off-by: Bradley Morgan <include@grrlz.net>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Adrian Huang <adrianhuang0701@gmail.com>
Cc: Aleksandr Nogikh <nogikh@google.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Marco Elver <elver@google.com>
Cc: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | kernel/signal.c | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/kernel/signal.c b/kernel/signal.c index e6e812f8b80f..a11c3c9afd2b 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -1214,6 +1214,7 @@ static inline bool has_si_pid_and_uid(struct kernel_siginfo *info) int send_signal_locked(int sig, struct kernel_siginfo *info, struct task_struct *t, enum pid_type type) { + struct kernel_siginfo rewritten; /* Should SIGKILL or SIGSTOP be received by a pid namespace init? */ bool force = false; @@ -1227,6 +1228,9 @@ int send_signal_locked(int sig, struct kernel_siginfo *info, /* SIGKILL and SIGSTOP is special or has ids */ struct user_namespace *t_user_ns; + rewritten = *info; + info = &rewritten; + rcu_read_lock(); t_user_ns = task_cred_xxx(t, user_ns); if (current_user_ns() != t_user_ns) { |