From 9d42d48a342aee208c1154696196497fdc556bbf Mon Sep 17 00:00:00 2001 From: Catalin Marinas Date: Mon, 23 Feb 2015 15:13:40 +0000 Subject: [PATCH] arm64: compat Fix siginfo_t -> compat_siginfo_t conversion on big endian The native (64-bit) sigval_t union contains sival_int (32-bit) and sival_ptr (64-bit). When a compat application invokes a syscall that takes a sigval_t value (as part of a larger structure, e.g. compat_sys_mq_notify, compat_sys_timer_create), the compat_sigval_t union is converted to the native sigval_t with sival_int overlapping with either the least or the most significant half of sival_ptr, depending on endianness. When the corresponding signal is delivered to a compat application, on big endian the current (compat_uptr_t)sival_ptr cast always returns 0 since sival_int corresponds to the top part of sival_ptr. This patch fixes copy_siginfo_to_user32() so that sival_int is copied to the compat_siginfo_t structure. Cc: Reported-by: Bamvor Jian Zhang Tested-by: Bamvor Jian Zhang Signed-off-by: Catalin Marinas --- arch/arm64/kernel/signal32.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) diff --git a/arch/arm64/kernel/signal32.c b/arch/arm64/kernel/signal32.c index c20a300e2213..d26fcd4cd6e6 100644 --- a/arch/arm64/kernel/signal32.c +++ b/arch/arm64/kernel/signal32.c @@ -154,8 +154,7 @@ int copy_siginfo_to_user32(compat_siginfo_t __user *to, const siginfo_t *from) case __SI_TIMER: err |= __put_user(from->si_tid, &to->si_tid); err |= __put_user(from->si_overrun, &to->si_overrun); - err |= __put_user((compat_uptr_t)(unsigned long)from->si_ptr, - &to->si_ptr); + err |= __put_user(from->si_int, &to->si_int); break; case __SI_POLL: err |= __put_user(from->si_band, &to->si_band); @@ -184,7 +183,7 @@ int copy_siginfo_to_user32(compat_siginfo_t __user *to, const siginfo_t *from) case __SI_MESGQ: /* But this is */ err |= __put_user(from->si_pid, &to->si_pid); err |= __put_user(from->si_uid, &to->si_uid); - err |= __put_user((compat_uptr_t)(unsigned long)from->si_ptr, &to->si_ptr); + err |= __put_user(from->si_int, &to->si_int); break; case __SI_SYS: err |= __put_user((compat_uptr_t)(unsigned long) -- GitLab