linux-kernel - Problem with find_first

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:	Sat, 16 Aug 2008 12:26:54 -0700 (PDT)
From:	Alex Dubov <oakad@...oo.com>
To:	Linux kernel mailing list <linux-kernel@...r.kernel.org>
Subject: Problem with find_first_bit function and kin

It's well may be that I'm just missing something obvious.

It seems to me that find_first_bit/find_next_bit functions return their
offsets "base 1" - first set bit is "1" and last is "bitmap size". This
means that if only the last bit in the bitmap is set, the returned value
will be indistinguishable from no bits set situation. Moreover, bit
manipulation functions appear to use "base 0" bit addresses, adding to the
inconvenience.

Is this a desired behavior? And, if yes, how is one supposed to deal with last bit of the bitmap?

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/