Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1169617

Re: [PATCH] hexdump: fix for non-naturally-aligned buffers

From Joe Perches <joe@perches.com>
Newsgroups linux.kernel
Subject Re: [PATCH] hexdump: fix for non-naturally-aligned buffers
Date 2015-06-21 18:50 +0200
Message-ID <pDQBr-2gk-5@gated-at.bofh.it> (permalink)
References <pDQrL-24S-7@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


On Sun, 2015-06-21 at 18:36 +0200,
=?UTF-8?q?Horacio=20Mijail=20Ant=C3=B3n=20Quiles?= wrote:
> Calling hex_dump_to_buffer() with a buffer non-naturally-aligned to the
> groupsize causes non-naturally-aligned memory accesses. This was causing
> a kernel panic on the BlackFin BF527, when such a call was made by 
> ubifs_scanned_corruption() in fs/ubifs/scan.c .
[]
> diff --git a/lib/hexdump.c b/lib/hexdump.c
[]
> @@ -123,6 +123,11 @@ int hex_dump_to_buffer(const void *buf, size_t len, int rowsize, int groupsize,
>  		groupsize = 1;
>  	if ((len % groupsize) != 0)	/* no mixed size output */
>  		groupsize = 1;
> +	
> +	/* fall back to 1-byte groups if buf is not naturally aligned */
> +	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
> +	    (((uintptr_t)buf % groupsize) != 0))
> +		groupsize = 1;

Maybe !IS_ALIGNED(buf, groupsize) reads better.


--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
Please read the FAQ at  http://www.tux.org/lkml/

Back to linux.kernel | Previous | NextPrevious in thread | Find similar | Unroll thread


Thread

[PATCH] hexdump: fix for non-naturally-aligned buffers =?UTF-8?q?Horacio=20Mijail=20Ant=C3=B3n=20Quiles?= <hmijail@gmail.com> - 2015-06-21 18:40 +0200
  Re: [PATCH] hexdump: fix for non-naturally-aligned buffers Joe Perches <joe@perches.com> - 2015-06-21 18:50 +0200

csiph-web