fs/signalfd.c: fix inconsistent return codes for signalfd4

[ Upstream commit a089e3fd5a ]

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@gmx.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Laurent Vivier <laurent@vivier.eu>
Link: http://lkml.kernel.org/r/20200530100707.GA10159@ls3530.fritz.box
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
This commit is contained in:
Helge Deller 2020-08-11 18:36:04 -07:00 committed by Greg Kroah-Hartman
parent 6afcb8b934
commit 7c89e40ede

View file

@ -313,9 +313,10 @@ 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);
}
@ -324,9 +325,10 @@ 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);
}