powerpc/security: Fix debugfs data leak on 32-bit
"powerpc_security_features" is "unsigned long", i.e. 32-bit or 64-bit, depending on the platform (PPC_FSL_BOOK3E or PPC_BOOK3S_64). Hence casting its address to "u64 *", and calling debugfs_create_x64() is wrong, and leaks 32-bit of nearby data to userspace on 32-bit platforms. While all currently defined SEC_FTR_* security feature flags fit in 32-bit, they all have "ULL" suffixes to make them 64-bit constants. Hence fix the leak by changing the type of "powerpc_security_features" (and the parameter types of its accessors) to "u64". This also allows to drop the cast. Fixes: 398af571 ("powerpc/security: Show powerpc_security_features in debugfs") Signed-off-by:Geert Uytterhoeven <geert+renesas@glider.be> Signed-off-by:
Michael Ellerman <mpe@ellerman.id.au> Link: https://lore.kernel.org/r/20191021142309.28105-1-geert+renesas@glider.be
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