From 5cfe8f1ba5eebe6f4b6e5858cdb1a5be4f3272a6 Mon Sep 17 00:00:00 2001
From: Jay Estabrook <jay.estabrook@gmail.com>
Date: Sat, 16 Nov 2013 16:45:31 -0800
Subject: [PATCH] alpha: Prevent a NULL ptr dereference in csum_partial_copy.
Introduced by 3ddc5b46a8e90f3c92 ("kernel-wide: fix missing validations
on __get/__put/__copy_to/__copy_from_user()").
Also fix some other places which could be problematic in a similar way,
although they hadn't been proved so, as far as I can tell.
Cc: Michael Cree <mcree@orcon.net.nz>
Signed-off-by: Matt Turner <mattst88@gmail.com>
---
arch/alpha/lib/csum_partial_copy.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)
diff --git a/arch/alpha/lib/csum_partial_copy.c b/arch/alpha/lib/csum_partial_copy.c
index ffb19b7da999c..ff3c10721caf6 100644
--- a/arch/alpha/lib/csum_partial_copy.c
+++ b/arch/alpha/lib/csum_partial_copy.c
@@ -130,7 +130,7 @@ csum_partial_cfu_aligned(const unsigned long __user *src, unsigned long *dst,
*dst = word | tmp;
checksum += carry;
}
- if (err) *errp = err;
+ if (err && errp) *errp = err;
return checksum;
}
@@ -185,7 +185,7 @@ csum_partial_cfu_dest_aligned(const unsigned long __user *src,
*dst = word | tmp;
checksum += carry;
}
- if (err) *errp = err;
+ if (err && errp) *errp = err;
return checksum;
}
@@ -242,7 +242,7 @@ csum_partial_cfu_src_aligned(const unsigned long __user *src,
stq_u(partial_dest | second_dest, dst);
out:
checksum += carry;
- if (err) *errp = err;
+ if (err && errp) *errp = err;
return checksum;
}
@@ -325,7 +325,7 @@ csum_partial_cfu_unaligned(const unsigned long __user * src,
stq_u(partial_dest | word | second_dest, dst);
checksum += carry;
}
- if (err) *errp = err;
+ if (err && errp) *errp = err;
return checksum;
}
@@ -339,7 +339,7 @@ csum_partial_copy_from_user(const void __user *src, void *dst, int len,
if (len) {
if (!access_ok(VERIFY_READ, src, len)) {
- *errp = -EFAULT;
+ if (errp) *errp = -EFAULT;
memset(dst, 0, len);
return sum;
}
--
GitLab