[PATCH v2 2/2] linux: Clear mode_t padding bits (BZ#25623)

[Andreas Schwab]

On Mär 04 2020, Adhemerval Zanella wrote:

> The kernel might not clear the padding value for the ipc_perm mode
> fields in compat mode (32 bit running on a 64 bit kernel).  It was
> fixed on v4.14 when the ipc compat code was refactored to move
> (commits 553f770ef71b, 469391684626, c0ebccb6fa1e).
>
> Although it is most likely a kernel issue, it was shown only due
> BZ#18231 fix which made all the SysVIPC mode_t 32-bit regardless of
> the kABI.
>
> This patch fixes it by explicit zeroing the upper bits for such

s/explicit/explicitly/

> cases.  The __ASSUME_SYSVIPC_BROKEN_MODE_T case already handles
> it with the shift.
>
> (The aarch64 ipc_priv.h is superflous since
> __ASSUME_SYSVIPC_DEFAULT_IPC_64 is now defined as default).
>
> Checked on i686-linux-gnu on 3.10 and on 4.15 kernel.

Ok.

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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