Commit-ID: 5ed386ec09a5d75bcf073967e55e895c2607a5c3
Gitweb: http://git.kernel.org/tip/5ed386ec09a5d75bcf073967e55e895c2607a5c3
Author: Joerg Roedel <jroe...@suse.de>
AuthorDate: Thu, 6 Apr 2017 16:19:22 +0200
Committer: Ingo Molnar <mi...@kernel.org>
CommitDate: Wed, 12 Apr 2017 08:40:58 +0200
x86/mpx: Correctly report do_mpx_bt_fault() failures to user-space
When this function fails it just sends a SIGSEGV signal to
user-space using force_sig(). This signal is missing
essential information about the cause, e.g. the trap_nr or
an error code.
Fix this by propagating the error to the only caller of
mpx_handle_bd_fault(), do_bounds(), which sends the correct
SIGSEGV signal to the process.
Signed-off-by: Joerg Roedel <jroe...@suse.de>
Cc: Andy Lutomirski <l...@kernel.org>
Cc: Borislav Petkov <b...@alien8.de>
Cc: Brian Gerst <brge...@gmail.com>
Cc: Dave Hansen <dave.han...@linux.intel.com>
Cc: Denys Vlasenko <dvlas...@redhat.com>
Cc: H. Peter Anvin <h...@zytor.com>
Cc: Josh Poimboeuf <jpoim...@redhat.com>
Cc: Linus Torvalds <torva...@linux-foundation.org>
Cc: Peter Zijlstra <pet...@infradead.org>
Cc: Thomas Gleixner <t...@linutronix.de>
Fixes: fe3d197f84319 ('x86, mpx: On-demand kernel allocation of bounds tables')
Link: http://lkml.kernel.org/r/1491488362-27198-1-git-send-email-j...@8bytes.org
Signed-off-by: Ingo Molnar <mi...@kernel.org>
---
arch/x86/mm/mpx.c | 10 +---------
1 file changed, 1 insertion(+), 9 deletions(-)
diff --git a/arch/x86/mm/mpx.c b/arch/x86/mm/mpx.c
index cd44ae7..1c34b76 100644
--- a/arch/x86/mm/mpx.c
+++ b/arch/x86/mm/mpx.c
@@ -526,15 +526,7 @@ int mpx_handle_bd_fault(void)
if (!kernel_managing_mpx_tables(current->mm))
return -EINVAL;
- if (do_mpx_bt_fault()) {
- force_sig(SIGSEGV, current);
- /*
- * The force_sig() is essentially "handling" this
- * exception, so we do not pass up the error
- * from do_mpx_bt_fault().
- */
- }
- return 0;
+ return do_mpx_bt_fault();
}
/*
