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94a3f78566
Eric Sandeen tracked an XFS on ARM corruption bug down to a function under fs/xfs/ involving some get_unaligned() calls on u64 pointers. As it turns out, calling ARM's get_unaligned() on a u64 pointer pointing to the following byte sequence: 80 81 82 83 84 85 86 87 would return ffffffff83828180 (LE mode.) This turns out to be because of implicit u8 -> int promotion in ARM's implementation of various helpers for get_unaligned(), causing them to accidentally return signed instead of unsigned values, which in turn caused the subsequent casts to unsigned long long in __get_unaligned_8_[bl]e() to sign-extend the lower words. Fix by casting the return values of __get_unaligned_[24]_[bl]e() to unsigned int. Cc: Eric Sandeen <sandeen@sandeen.net> Cc: Rabeeh Khoury <rabeeh@marvell.com> Cc: Nicolas Pitre <nico@marvell.com> Signed-off-by: Lennert Buytenhek <buytenh@marvell.com> Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>