tree cd0a4971a4bba159285a7a1a3e0a612bc2750037
parent a82c13d29985a4d99dacd700b497f0c062fe3625
author Yuntao Wang <yuntao.wang@linux.dev> 1716998816 +0800
committer Christian Brauner <brauner@kernel.org> 1717053107 +0200

fs/file: fix the check in find_next_fd()

The maximum possible return value of find_next_zero_bit(fdt->full_fds_bits,
maxbit, bitbit) is maxbit. This return value, multiplied by BITS_PER_LONG,
gives the value of bitbit, which can never be greater than maxfd, it can
only be equal to maxfd at most, so the following check 'if (bitbit > maxfd)'
will never be true.

Moreover, when bitbit equals maxfd, it indicates that there are no unused
fds, and the function can directly return.

Fix this check.

Signed-off-by: Yuntao Wang <yuntao.wang@linux.dev>
Link: https://lore.kernel.org/r/20240529160656.209352-1-yuntao.wang@linux.dev
Reviewed-by: Jan Kara <jack@suse.cz>
Signed-off-by: Christian Brauner <brauner@kernel.org>