diff options
author | Sven Van Asbroeck <thesven73@gmail.com> | 2019-06-17 14:23:54 -0400 |
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committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-06-18 09:10:02 +0200 |
commit | 2472d64af2d3561954e2f05365a67692bb852f2a (patch) | |
tree | 970ea3d44d0f259e58f629d49b419c91a365139f | |
parent | 5669245b57df8a0edae475e06d1b851729a21457 (diff) | |
download | linux-2472d64af2d3561954e2f05365a67692bb852f2a.tar.bz2 |
firmware: improve LSM/IMA security behaviour
The firmware loader queries if LSM/IMA permits it to load firmware
via the sysfs fallback. Unfortunately, the code does the opposite:
it expressly permits sysfs fw loading if security_kernel_load_data(
LOADING_FIRMWARE) returns -EACCES. This happens because a
zero-on-success return value is cast to a bool that's true on success.
Fix the return value handling so we get the correct behaviour.
Fixes: 6e852651f28e ("firmware: add call to LSM hook before firmware sysfs fallback")
Cc: Stable <stable@vger.kernel.org>
Cc: Mimi Zohar <zohar@linux.vnet.ibm.com>
Cc: Kees Cook <keescook@chromium.org>
To: Luis Chamberlain <mcgrof@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Sven Van Asbroeck <TheSven73@gmail.com>
Reviewed-by: Mimi Zohar <zohar@linux.ibm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r-- | drivers/base/firmware_loader/fallback.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index b5cd96fd0e77..29becea1910d 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -659,7 +659,7 @@ static bool fw_run_sysfs_fallback(enum fw_opt opt_flags) /* Also permit LSMs and IMA to fail firmware sysfs fallback */ ret = security_kernel_load_data(LOADING_FIRMWARE); if (ret < 0) - return ret; + return false; return fw_force_sysfs_fallback(opt_flags); } |