[alpha] Prevent a NULL ptr dereference in csum_partial_copy

svn path=/dists/sid/linux/; revision=20895

debian/changelog

@@ -52,6 +52,7 @@ linux (3.12.5-1) UNRELEASED; urgency=medium
   * media: az6007: support Technisat Cablestar Combo HDCI (minus remote)
     (Closes: #732106)
   * linux-source: Compress with gzip -1 (Closes: #725492)
+  * [alpha] Prevent a NULL ptr dereference in csum_partial_copy
 
   [ Ian Campbell ]
   * [armel/kirkwood+orion] Reenable MARVELL_PHY (Closes: #723177)

debian/patches/bugfix/all/alpha-Prevent-a-NULL-ptr-dereference-in-csum_partial.patch

@@ -0,0 +1,66 @@
+From: Jay Estabrook <jay.estabrook@gmail.com>
+Date: Sat, 16 Nov 2013 16:45:31 -0800
+Subject: alpha: Prevent a NULL ptr dereference in csum_partial_copy.
+Origin: https://git.kernel.org/linus/5cfe8f1ba5eebe6f4b6e5858cdb1a5be4f3272a6
+
+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 ffb19b7..ff3c1072 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;
+ 		}

debian/patches/series

@@ -81,3 +81,4 @@ bugfix/all/xfs-underflow-bug-in-xfs_attrlist_by_handle.patch
 bugfix/arm/ahci-imx-Explicitly-clear-IMX6Q_GPR13_SATA_MPLL_CLK_.patch
 bugfix/all/disable-some-marvell-phys.patch
 features/all/media-az6007-support-Technisat-Cablestar-Combo-HDCI-.patch
+bugfix/all/alpha-Prevent-a-NULL-ptr-dereference-in-csum_partial.patch