From: AKASHI Takahiro <takahiro.akashi@linaro.org>
Date: Thu, 4 Sep 2014 14:48:01 +0000 (+0100)
Subject: arm64: add SIGSYS siginfo for compat task
X-Git-Tag: firefly_0821_release~4090^2~180
X-Git-Url: http://plrg.eecs.uci.edu/git/?a=commitdiff_plain;h=77227239d20ac6381fb1aee7b7cc902f0d14cd85;p=firefly-linux-kernel-4.4.55.git

arm64: add SIGSYS siginfo for compat task

Note: This patch is from v6 of Takahiro's proposed
"arm64: add seccomp support" patchset (leecam@google.com)

SIGSYS is primarily used in secure computing to notify tracer.
This patch allows signal handler on compat task to get correct information
with SA_SYSINFO specified when this signal is delivered.

Signed-off-by: AKASHI Takahiro <takahiro.akashi <at> linaro.org>
---

diff --git a/arch/arm64/include/asm/compat.h b/arch/arm64/include/asm/compat.h
index ae0004fe6c23..a79da08994f2 100644
--- a/arch/arm64/include/asm/compat.h
+++ b/arch/arm64/include/asm/compat.h
@@ -191,6 +191,13 @@ typedef struct compat_siginfo {
 			compat_long_t _band;	/* POLL_IN, POLL_OUT, POLL_MSG */
 			int _fd;
 		} _sigpoll;
+
+		/* SIGSYS */
+		struct {
+			compat_uptr_t _call_addr; /* calling user insn */
+			int _syscall;	/* triggering system call number */
+			unsigned int _arch;	/* AUDIT_ARCH_* of syscall */
+		} _sigsys;
 	} _sifields;
 } compat_siginfo_t;
 
diff --git a/arch/arm64/kernel/signal32.c b/arch/arm64/kernel/signal32.c
index b4692837e7ab..e1b8b9fb274e 100644
--- a/arch/arm64/kernel/signal32.c
+++ b/arch/arm64/kernel/signal32.c
@@ -211,6 +211,14 @@ int copy_siginfo_to_user32(compat_siginfo_t __user *to, siginfo_t *from)
 		err |= __put_user(from->si_uid, &to->si_uid);
 		err |= __put_user((compat_uptr_t)(unsigned long)from->si_ptr, &to->si_ptr);
 		break;
+#ifdef __ARCH_SIGSYS
+	case __SI_SYS:
+		err |= __put_user((compat_uptr_t)(unsigned long)
+				from->si_call_addr, &to->si_call_addr);
+		err |= __put_user(from->si_syscall, &to->si_syscall);
+		err |= __put_user(from->si_arch, &to->si_arch);
+		break;
+#endif
 	default: /* this is just in case for now ... */
 		err |= __put_user(from->si_pid, &to->si_pid);
 		err |= __put_user(from->si_uid, &to->si_uid);