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Subject[PATCH] Fix an inproper alignment accessing in irda protocol stack
Hi all,

For "struct irda_device_info" in irda.h:
struct irda_device_info {
__u32 saddr; /* Address of local interface */
__u32 daddr; /* Address of remote device */
char info[22]; /* Description */
__u8 charset; /* Charset used for description */
__u8 hints[2]; /* Hint bits */
};
The "hints" member aligns at the third byte of a word, an odd
address. So if we visit "hints" as a short in irlmp.c:

u16ho(irlmp->discovery_cmd.data.hints) = irlmp->hints.word;

will cause alignment problem on some machines. Architectures with
strict alignment rules do not allow 16-bit read on an odd address.

Signed-off-by: Luke Yang <luke.adi@gmail.com>

irlmp.c | 3 ++-
1 files changed, 2 insertions(+), 1 deletion(-)

--- net/irda/irlmp.c.old 2006-06-08 14:49:20.000000000 +0800
+++ net/irda/irlmp.c 2006-06-08 14:54:29.000000000 +0800
@@ -849,7 +849,8 @@
}

/* Construct new discovery info to be used by IrLAP, */
- u16ho(irlmp->discovery_cmd.data.hints) = irlmp->hints.word;
+ irlmp->discovery_cmd.data.hints[0] = irlmp->hints.word & 0xff;
+ irlmp->discovery_cmd.data.hints[1] = (irlmp->hints.word & 0xff00) >> 8;

/*
* Set character set for device name (we use ASCII), and
--
Best regards,
Luke Yang
luke.adi@gmail.com
--- net/irda/irlmp.c.old 2006-06-08 14:49:20.000000000 +0800
+++ net/irda/irlmp.c 2006-06-08 14:54:29.000000000 +0800
@@ -849,7 +849,8 @@
}

/* Construct new discovery info to be used by IrLAP, */
- u16ho(irlmp->discovery_cmd.data.hints) = irlmp->hints.word;
+ irlmp->discovery_cmd.data.hints[0] = irlmp->hints.word & 0xff;
+ irlmp->discovery_cmd.data.hints[1] = (irlmp->hints.word & 0xff00) >> 8;

/*
* Set character set for device name (we use ASCII), and
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