From b89f50c78c00e9494cc31d5231f0db65210aa5f7 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 10 Oct 2018 20:29:44 -0500 Subject: [PATCH] signal: Guard against negative signal numbers in copy_siginfo_from_user32 While fixing an out of bounds array access in known_siginfo_layout reported by the kernel test robot it became apparent that the same bug exists in siginfo_layout and affects copy_siginfo_from_user32. The straight forward fix that makes guards against making this mistake in the future and should keep the code size small is to just take an unsigned signal number instead of a signed signal number, as I did to fix known_siginfo_layout. Cc: stable@vger.kernel.org Fixes: 31000cb0a490 ("signal: Remove kernel interal si_code magic") Signed-off-by: "Eric W. Biederman" --- include/linux/signal.h | 2 +- kernel/signal.c | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/include/linux/signal.h b/include/linux/signal.h index 706a499d1eb1d..200ed96a05afe 100644 --- a/include/linux/signal.h +++ b/include/linux/signal.h @@ -40,7 +40,7 @@ enum siginfo_layout { SIL_SYS, }; -enum siginfo_layout siginfo_layout(int sig, int si_code); +enum siginfo_layout siginfo_layout(unsigned sig, int si_code); /* * Define some primitives to manipulate sigset_t. diff --git a/kernel/signal.c b/kernel/signal.c index 5f5bf374512b8..4fd431ce4f91e 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -2879,7 +2879,7 @@ static bool known_siginfo_layout(unsigned sig, int si_code) return false; } -enum siginfo_layout siginfo_layout(int sig, int si_code) +enum siginfo_layout siginfo_layout(unsigned sig, int si_code) { enum siginfo_layout layout = SIL_KILL; if ((si_code > SI_USER) && (si_code < SI_KERNEL)) { -- 2.39.5