2.6.36-stable review patch.  If anyone has any objections, please let us know.

------------------

From: James Jones <[email protected]>

commit 0e91ec0c06d2cd15071a6021c94840a50e6671aa upstream.

The find_next_bit, find_first_bit, find_next_zero_bit
and find_first_zero_bit functions were not properly
clamping to the maxbit argument at the bit level. They
were instead only checking maxbit at the byte level.
To fix this, add a compare and a conditional move
instruction to the end of the common bit-within-the-
byte code used by all the functions and be sure not to
clobber the maxbit argument before it is used.

Reviewed-by: Nicolas Pitre <[email protected]>
Tested-by: Stephen Warren <[email protected]>
Signed-off-by: James Jones <[email protected]>
Signed-off-by: Russell King <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 arch/arm/lib/findbit.S |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

--- a/arch/arm/lib/findbit.S
+++ b/arch/arm/lib/findbit.S
@@ -174,8 +174,8 @@ ENDPROC(_find_next_bit_be)
  */
 .L_found:
 #if __LINUX_ARM_ARCH__ >= 5
-               rsb     r1, r3, #0
-               and     r3, r3, r1
+               rsb     r0, r3, #0
+               and     r3, r3, r0
                clz     r3, r3
                rsb     r3, r3, #31
                add     r0, r2, r3
@@ -190,5 +190,7 @@ ENDPROC(_find_next_bit_be)
                addeq   r2, r2, #1
                mov     r0, r2
 #endif
+               cmp     r1, r0                  @ Clamp to maxbit
+               movlo   r0, r1
                mov     pc, lr
 


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