From: "Allan, Bruce W" <bruce.w.allan@intel.com>
To: "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>
CC: "Allan, Bruce W" <bruce.w.allan@intel.com>
Subject: bug in sscanf()?
Thread-Topic: bug in sscanf()?
Thread-Index: Ac8NbKAkgHr1INwXQ8WF2Iu0CYn2gw==
Date: Thu, 9 Jan 2014 18:57:29 +0000
Message-ID: <804857E1F29AAC47BF68C404FC60A1846542A6B2@ORSMSX105.amr.corp.intel.com>
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The kernel version of sscanf() does not allow for scanning a string with multiple concatenated integers even when maximum field widths are specified to stop reading the string to delineate the individual integers.  For example, trying to read the (3) 32-bit hexadecimal integers deadbeef, 12345678 and deadc0de when provided as a concatenated string with:

	int num;
	u32 i, j, k;
	
	num = sscanf("deadbeef12345678deadc0de", "%8x%8x%8x", &i, &j, &k);

will return the number of input items successfully matched and assigned as 3, the 32-bit integers j and k will have the expected values, but i will be 0.

The libc version of sscanf(), however, will set the value of i to deadbeef.

Should this be expected with the kernel version or is it a bug?

Thanks,
Bruce.

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