linux-kernel - [PATCH 1/2] signal.7: Clearly describe ucontext kernel dump to userspace

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20240607123119.769044-2-dev.jain@arm.com>
Date: Fri,  7 Jun 2024 18:01:18 +0530
From: Dev Jain <dev.jain@....com>
To: alx@...nel.org,
	linux-man@...r.kernel.org
Cc: mingo@...nel.org,
	tglx@...utronix.de,
	mark.rutland@....com,
	ryan.roberts@....com,
	broonie@...nel.org,
	suzuki.poulose@....com,
	Anshuman.Khandual@....com,
	DeepakKumar.Mishra@....com,
	AneeshKumar.KizhakeVeetil@....com,
	linux-kernel@...r.kernel.org,
	Dev Jain <dev.jain@....com>
Subject: [PATCH 1/2] signal.7: Clearly describe ucontext kernel dump to userspace

The set of blocked signals is updated from struct sigaction after the
kernel dumps ucontext. Mention this to avoid misunderstanding.

Signed-off-by: Dev Jain <dev.jain@....com>
---
 man/man7/signal.7 | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/man/man7/signal.7 b/man/man7/signal.7
index 4ba5306c8..17e75c86d 100644
--- a/man/man7/signal.7
+++ b/man/man7/signal.7
@@ -282,7 +282,15 @@ the thread's alternate signal stack settings.
 .B SA_SIGINFO
 flag, then the above information is accessible via the
 .I ucontext_t
-object that is pointed to by the third argument of the signal handler.)
+object that is pointed to by the third argument of the signal handler.
+We emphasize on the fact that this object contains context information
+of the thread, present before jumping into the handler; the set of
+blocked signals for the current thread would be updated from struct
+sigaction only after
+.I ucontext_t
+has been dumped to userspace. This semantically makes sense since the
+context for which the signals have been blocked, remains only during
+execution of the handler.)
 .IP (1.4)
 Any signals specified in
 .I act\->sa_mask
-- 
2.34.1