Hi Kees, Thanks for sending out. This looks different than your other patch series. We should get the first 5 patches accepted now though as they are simple cleanups and fixes. That will reduce the number of outstanding patches in the series. At first glance the issue with the changes after that is the existing API assumes it has read the whole file and failed if it did not. Now, if the file is larger than the amount requested there is no indication? On 2020-07-17 10:42 a.m., Kees Cook wrote:
Hi, Here's my attempt at clearing the path to partial read support in kernel_read_file(), which fixes a number of issues along the way. I'm still fighting with the firmware test suite (it doesn't seem to pass for me even in stock v5.7... ?) But I don't want to block Scott's work[1] any this week, so here's the series as it is currently. The primary difference to Scott's approach is to avoid adding a new set of functions and just adapt the existing APIs to deal with "offset". Also, the fixes for the enum are first in the series so they can be backported without the header file relocation. I'll keep poking at the firmware tests... -Kees [1] https://lore.kernel.org/lkml/202007161415.10D015477@keescook/ Kees Cook (12): firmware_loader: EFI firmware loader must handle pre-allocated buffer fs/kernel_read_file: Remove FIRMWARE_PREALLOC_BUFFER enum fs/kernel_read_file: Remove FIRMWARE_EFI_EMBEDDED enum fs/kernel_read_file: Split into separate source file fs/kernel_read_file: Remove redundant size argument fs/kernel_read_file: Switch buffer size arg to size_t fs/kernel_read_file: Add file_size output argument LSM: Introduce kernel_post_load_data() hook firmware_loader: Use security_post_load_data() module: Call security_kernel_post_load_data() LSM: Add "contents" flag to kernel_read_file hook fs/kernel_file_read: Add "offset" arg for partial reads Scott Branden (1): fs/kernel_read_file: Split into separate include file drivers/base/firmware_loader/fallback.c | 8 +- .../base/firmware_loader/fallback_platform.c | 12 +- drivers/base/firmware_loader/main.c | 13 +- fs/Makefile | 3 +- fs/exec.c | 132 +----------- fs/kernel_read_file.c | 189 ++++++++++++++++++ include/linux/fs.h | 39 ---- include/linux/ima.h | 19 +- include/linux/kernel_read_file.h | 55 +++++ include/linux/lsm_hook_defs.h | 6 +- include/linux/lsm_hooks.h | 12 ++ include/linux/security.h | 19 +- kernel/kexec.c | 2 +- kernel/kexec_file.c | 18 +- kernel/module.c | 24 ++- security/integrity/digsig.c | 8 +- security/integrity/ima/ima_fs.c | 9 +- security/integrity/ima/ima_main.c | 58 ++++-- security/integrity/ima/ima_policy.c | 1 + security/loadpin/loadpin.c | 17 +- security/security.c | 26 ++- security/selinux/hooks.c | 8 +- 22 files changed, 432 insertions(+), 246 deletions(-) create mode 100644 fs/kernel_read_file.c create mode 100644 include/linux/kernel_read_file.h