lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Wed, 19 Aug 2020 20:01:55 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Helge Deller <deller@....de>,
        Andrew Morton <akpm@...ux-foundation.org>,
        Alexander Viro <viro@...iv.linux.org.uk>,
        Laurent Vivier <laurent@...ier.eu>,
        Linus Torvalds <torvalds@...ux-foundation.org>,
        Sasha Levin <sashal@...nel.org>, linux-fsdevel@...r.kernel.org
Subject: [PATCH AUTOSEL 5.7 24/24] fs/signalfd.c: fix inconsistent return codes for signalfd4

From: Helge Deller <deller@....de>

[ Upstream commit a089e3fd5a82aea20f3d9ec4caa5f4c65cc2cfcc ]

The kernel signalfd4() syscall returns different error codes when called
either in compat or native mode.  This behaviour makes correct emulation
in qemu and testing programs like LTP more complicated.

Fix the code to always return -in both modes- EFAULT for unaccessible user
memory, and EINVAL when called with an invalid signal mask.

Signed-off-by: Helge Deller <deller@....de>
Signed-off-by: Andrew Morton <akpm@...ux-foundation.org>
Cc: Alexander Viro <viro@...iv.linux.org.uk>
Cc: Laurent Vivier <laurent@...ier.eu>
Link: http://lkml.kernel.org/r/20200530100707.GA10159@ls3530.fritz.box
Signed-off-by: Linus Torvalds <torvalds@...ux-foundation.org>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 fs/signalfd.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/fs/signalfd.c b/fs/signalfd.c
index 44b6845b071c3..5b78719be4455 100644
--- a/fs/signalfd.c
+++ b/fs/signalfd.c
@@ -314,9 +314,10 @@ SYSCALL_DEFINE4(signalfd4, int, ufd, sigset_t __user *, user_mask,
 {
 	sigset_t mask;
 
-	if (sizemask != sizeof(sigset_t) ||
-	    copy_from_user(&mask, user_mask, sizeof(mask)))
+	if (sizemask != sizeof(sigset_t))
 		return -EINVAL;
+	if (copy_from_user(&mask, user_mask, sizeof(mask)))
+		return -EFAULT;
 	return do_signalfd4(ufd, &mask, flags);
 }
 
@@ -325,9 +326,10 @@ SYSCALL_DEFINE3(signalfd, int, ufd, sigset_t __user *, user_mask,
 {
 	sigset_t mask;
 
-	if (sizemask != sizeof(sigset_t) ||
-	    copy_from_user(&mask, user_mask, sizeof(mask)))
+	if (sizemask != sizeof(sigset_t))
 		return -EINVAL;
+	if (copy_from_user(&mask, user_mask, sizeof(mask)))
+		return -EFAULT;
 	return do_signalfd4(ufd, &mask, 0);
 }
 
-- 
2.25.1

Powered by blists - more mailing lists