From: Helge Deller deller@gmx.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@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 --- 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); }