This series enhances the ioctl path so that userspace callers are able to reliably check all error bits for their operation. The current implementation poses the problem of error bits which the caller cannot check, this is potentially a security issue. If the phrase security issue has woken you up, but you haven't been using: mmc-utils sanitize mmc-utils erase secure-trim{1|2} mmc-utils secure-erase mmc-utils rpmb write-block you can go back to sleep, sorry to bother you. If you have, you are probably still fine, if there was no active attacker sabotaging your eMMC, the secure operation probably succeeded. There is just no way to confirm that it actually has. Examples include e.g. a flash-fail of the eMMC. Card behavior differs here, R1 bit 19 could be set, many cards will just shut off on flash-fail, so if you want to play with this patch I would suggest aiming for WP_ERASE_SKIP, although that technically doesn't need the patch, as WP groups could be queried before and after erase. sudo ./mmc writeprotect user set temp 0x0 $(($(blockdev --getsz /dev/mmcblk2))) /dev/mmcblk2 sudo ./mmc erase secure-erase 0 $(($(blockdev --getsz /dev/mmcblk2)-1)) /dev/mmcblk2 will yield Executing Secure Erase from 0x00000000 to 0x0773ffff High Capacity Erase Unit Size=524288 bytes High Capacity Erase Timeout=600 ms High Capacity Write Protect Group Size=2097152 bytes RSP0: 0x00008900 # added by author, this is what the patch will add to RSP0 Secure Erase Succeed! even though no erase is issued. v3: - restored check on rpmb reads - refactored to use __mmc_poll_for_busy directly v2: - removed extra flag and made it default behavior for write or R1B - aggregate error flag in resp[0] instead of abusing resp[1] - avoid open loop busy polling and reuse __mmc_poll_for_busy Christian Loehle (1): mmc: block: ioctl: Add PROG-error aggregation drivers/mmc/core/block.c | 26 +++++++++++++++----------- drivers/mmc/core/mmc_ops.c | 14 +++++++------- drivers/mmc/core/mmc_ops.h | 9 +++++++++ 3 files changed, 31 insertions(+), 18 deletions(-) -- 2.37.3
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