On Thu, Apr 08, 2021 at 09:15:06AM -0400, Chris von Recklinghausen wrote: > Suspend fails on a system in fips mode because md5 is used for the e820 > integrity check and is not available. Use crc32 instead. > > This patch changes the integrity check algorithm from md5 to > crc32. This integrity check is used only to verify accidental > corruption of the hybernation data and is not intended as a > cryptographic integrity check. > Md5 is overkill in this case and also disabled in FIPS mode because it > is known to be broken for cryptographic purposes. > > Fixes: 62a03defeabd ("PM / hibernate: Verify the consistent of e820 memory map > by md5 digest") > > Tested-by: Dexuan Cui <de...@microsoft.com> > Reviewed-by: Dexuan Cui <de...@microsoft.com> > Signed-off-by: Chris von Recklinghausen <creck...@redhat.com> > --- > v1 -> v2 > bump up RESTORE_MAGIC > v2 -> v3 > move embelishment from cover letter to commit comments (no code change) > v3 -> v4 > add note to comments that md5 isn't used for encryption here. > v4 -> v5 > reword comment per Simo's suggestion > > arch/x86/power/hibernate.c | 35 +++++++++++++++++++---------------- > 1 file changed, 19 insertions(+), 16 deletions(-) > > diff --git a/arch/x86/power/hibernate.c b/arch/x86/power/hibernate.c > index cd3914fc9f3d..b56172553275 100644 > --- a/arch/x86/power/hibernate.c > +++ b/arch/x86/power/hibernate.c > @@ -55,31 +55,31 @@ int pfn_is_nosave(unsigned long pfn) > } > > > -#define MD5_DIGEST_SIZE 16 > +#define CRC32_DIGEST_SIZE 16 > > struct restore_data_record { > unsigned long jump_address; > unsigned long jump_address_phys; > unsigned long cr3; > unsigned long magic; > - u8 e820_digest[MD5_DIGEST_SIZE]; > + u8 e820_digest[CRC32_DIGEST_SIZE]; > }; > > -#if IS_BUILTIN(CONFIG_CRYPTO_MD5) > +#if IS_BUILTIN(CONFIG_CRYPTO_CRC32)
Should CONFIG_CRYPTO_CRC32 be getting selected from somewhere? If that is too hard because it would pull in too much of the crypto API, maybe using the library interface to CRC-32 (lib/crc32.c) would be a better fit? - Eric