[PATCH] lib: Fix bug in int_sqrt() for 64 bit longs

The implementation of int_sqrt() assumes that longs have 32 bits.  On
systems that have 64 bit longs this will result in gross errors when the
argument to the function is greater than 2^32 - 1 on such systems.  I doubt
whether any such use is currently made of int_sqrt() but the attached patch
fixes the problem anyway.

Signed-off-by: Peter Williams <pwil3058@bigpond.com.au>
Cc: Dave Jones <davej@codemonkey.org.uk>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This commit is contained in:
Peter Williams 2006-02-03 03:04:33 -08:00 committed by Linus Torvalds
parent 6bf8d889ed
commit f0c00257d6

View file

@ -15,7 +15,7 @@ unsigned long int_sqrt(unsigned long x)
op = x;
res = 0;
one = 1 << 30;
one = 1UL << (BITS_PER_LONG - 2);
while (one > op)
one >>= 2;