commit bce9b042ec73e8662b8119d4ca47e7c78b20d0bf
author Thomas Gleixner <tglx@linutronix.de> Wed Jul 08 21:28:05 2020 +0200
committer Thomas Gleixner <tglx@linutronix.de> Thu Jul 09 11:18:29 2020 +0200
tree 594c65f3873aeecc627645fc03ce635d65577f17
parent a4c0e91d1d65bc58f928b80ed824e10e165da22c

x86/traps: Disable interrupts in exc_aligment_check()

exc_alignment_check() fails to disable interrupts before returning to the
entry code.

Fixes: ca4c6a9858c2 ("x86/traps: Make interrupt enable/disable symmetric in C code")
Reported-by: syzbot+0889df9502bc0f112b31@syzkaller.appspotmail.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Andy Lutomirski <luto@kernel.org>
Link: https://lkml.kernel.org/r/20200708192934.076519438@linutronix.de

arch/x86/kernel/traps.c

diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c
index 6ed8cc5..4f3a509 100644
--- a/arch/x86/kernel/traps.c
+++ b/arch/x86/kernel/traps.c
@@ -299,6 +299,8 @@ DEFINE_IDTENTRY_ERRORCODE(exc_alignment_check)
 
 	do_trap(X86_TRAP_AC, SIGBUS, "alignment check", regs,
 		error_code, BUS_ADRALN, NULL);
+
+	local_irq_disable();
 }
 
 #ifdef CONFIG_VMAP_STACK