linuxppc-dev.lists.ozlabs.org archive mirror
 help / color / mirror / Atom feed
From: Paul Mackerras <paulus@samba.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linuxppc-dev@ozlabs.org, David Miller <davem@davemloft.net>
Subject: [PATCH 1/2] lib: Fix generic strnlen_user for 32-bit big-endian machines
Date: Mon, 28 May 2012 12:59:56 +1000	[thread overview]
Message-ID: <20120528025956.GA6822@bloggs.ozlabs.ibm.com> (raw)

The aligned_byte_mask() definition is wrong for 32-bit big-endian
machines: the "7-(n)" part of the definition assumes a long is 8
bytes.  This fixes it by using BITS_PER_LONG - 8 instead of 8*7.
Tested on 32-bit and 64-bit PowerPC.

Signed-off-by: Paul Mackerras <paulus@samba.org>
---
 lib/strnlen_user.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/lib/strnlen_user.c b/lib/strnlen_user.c
index 90900ec..a28df52 100644
--- a/lib/strnlen_user.c
+++ b/lib/strnlen_user.c
@@ -8,7 +8,7 @@
 #ifdef __LITTLE_ENDIAN
 #  define aligned_byte_mask(n) ((1ul << 8*(n))-1)
 #else
-#  define aligned_byte_mask(n) (~0xfful << 8*(7-(n)))
+#  define aligned_byte_mask(n) (~0xfful << (BITS_PER_LONG - 8 - 8*(n)))
 #endif
 
 /*
-- 
1.7.10.rc3.219.g53414

             reply	other threads:[~2012-05-28  2:59 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-05-28  2:59 Paul Mackerras [this message]
2012-05-28  3:03 ` [PATCH 2/2] powerpc: Use the new generic strncpy_from_user() and strnlen_user() Paul Mackerras
2012-05-28  3:56   ` David Miller
2012-05-28  3:55 ` [PATCH 1/2] lib: Fix generic strnlen_user for 32-bit big-endian machines David Miller

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20120528025956.GA6822@bloggs.ozlabs.ibm.com \
    --to=paulus@samba.org \
    --cc=davem@davemloft.net \
    --cc=linuxppc-dev@ozlabs.org \
    --cc=torvalds@linux-foundation.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).