From ed40866ec7d328b3dfb70db7e2011640a16202c3 Mon Sep 17 00:00:00 2001
From: Ilya Leoshkevich <iii@linux.ibm.com>
Date: Thu, 4 May 2023 16:40:20 +0200
Subject: [PATCH] statfs: enforce statfs[64] structure initialization
Git-commit: ed40866ec7d328b3dfb70db7e2011640a16202c3
Patch-mainline: v6.4-rc3
References: git-fixes
s390's struct statfs and struct statfs64 contain padding, which
field-by-field copying does not set. Initialize the respective structs
with zeros before filling them and copying them to userspace, like it's
already done for the compat versions of these structs.
Found by KMSAN.
[agordeev@linux.ibm.com: fixed typo in patch description]
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Cc: stable@vger.kernel.org # v4.14+
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/r/20230504144021.808932-2-iii@linux.ibm.com
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>
Acked-by: Anthony Iliopoulos <ailiop@suse.com>
---
fs/statfs.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/fs/statfs.c b/fs/statfs.c
index 0ba34c135593..96d1c3edf289 100644
--- a/fs/statfs.c
+++ b/fs/statfs.c
@@ -130,6 +130,7 @@ static int do_statfs_native(struct kstatfs *st, struct statfs __user *p)
if (sizeof(buf) == sizeof(*st))
memcpy(&buf, st, sizeof(*st));
else {
+ memset(&buf, 0, sizeof(buf));
if (sizeof buf.f_blocks == 4) {
if ((st->f_blocks | st->f_bfree | st->f_bavail |
st->f_bsize | st->f_frsize) &
@@ -158,7 +159,6 @@ static int do_statfs_native(struct kstatfs *st, struct statfs __user *p)
buf.f_namelen = st->f_namelen;
buf.f_frsize = st->f_frsize;
buf.f_flags = st->f_flags;
- memset(buf.f_spare, 0, sizeof(buf.f_spare));
}
if (copy_to_user(p, &buf, sizeof(buf)))
return -EFAULT;
@@ -171,6 +171,7 @@ static int do_statfs64(struct kstatfs *st, struct statfs64 __user *p)
if (sizeof(buf) == sizeof(*st))
memcpy(&buf, st, sizeof(*st));
else {
+ memset(&buf, 0, sizeof(buf));
buf.f_type = st->f_type;
buf.f_bsize = st->f_bsize;
buf.f_blocks = st->f_blocks;
@@ -182,7 +183,6 @@ static int do_statfs64(struct kstatfs *st, struct statfs64 __user *p)
buf.f_namelen = st->f_namelen;
buf.f_frsize = st->f_frsize;
buf.f_flags = st->f_flags;
- memset(buf.f_spare, 0, sizeof(buf.f_spare));
}
if (copy_to_user(p, &buf, sizeof(buf)))
return -EFAULT;
--
2.43.0