| Message ID | 1527616920-5415-5-git-send-email-zohar@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, May 29, 2018 at 02:01:56PM -0400, Mimi Zohar wrote: > Add an LSM hook prior to allowing firmware sysfs fallback loading. Acked-by: Luis R. Rodriguez <mcgrof@kernel.org> > Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> > Cc: Luis R. Rodriguez <mcgrof@suse.com> > Cc: David Howells <dhowells@redhat.com> > Cc: Kees Cook <keescook@chromium.org> > > Changelog v4: > - call new LSM security_kernel_arg hook > > Changelog v2: > - call security_kernel_read_blob() > - rename the READING_FIRMWARE_FALLBACK kernel_read_file_id enumeration to > READING_FIRMWARE_FALLBACK_SYSFS. > --- > drivers/base/firmware_loader/fallback.c | 7 +++++++ > 1 file changed, 7 insertions(+) > > diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c > index 358354148dec..2443bda81631 100644 > --- a/drivers/base/firmware_loader/fallback.c > +++ b/drivers/base/firmware_loader/fallback.c > @@ -651,6 +651,8 @@ static bool fw_force_sysfs_fallback(unsigned int opt_flags) > > static bool fw_run_sysfs_fallback(unsigned int opt_flags) > { > + int ret; > + > if (fw_fallback_config.ignore_sysfs_fallback) { > pr_info_once("Ignoring firmware sysfs fallback due to sysctl knob\n"); > return false; > @@ -659,6 +661,11 @@ static bool fw_run_sysfs_fallback(unsigned int opt_flags) > if ((opt_flags & FW_OPT_NOFALLBACK)) > return false; > > + /* Also permit LSMs and IMA to fail firmware sysfs fallback */ > + ret = security_kernel_load_data(LOADING_FIRMWARE); > + if (ret < 0) > + return ret; > + > return fw_force_sysfs_fallback(opt_flags); > } > > -- > 2.7.5 > >
diff --git a/drivers/base/firmware_loader/fallback.c b/drivers/base/firmware_loader/fallback.c index 358354148dec..2443bda81631 100644 --- a/drivers/base/firmware_loader/fallback.c +++ b/drivers/base/firmware_loader/fallback.c @@ -651,6 +651,8 @@ static bool fw_force_sysfs_fallback(unsigned int opt_flags) static bool fw_run_sysfs_fallback(unsigned int opt_flags) { + int ret; + if (fw_fallback_config.ignore_sysfs_fallback) { pr_info_once("Ignoring firmware sysfs fallback due to sysctl knob\n"); return false; @@ -659,6 +661,11 @@ static bool fw_run_sysfs_fallback(unsigned int opt_flags) if ((opt_flags & FW_OPT_NOFALLBACK)) return false; + /* Also permit LSMs and IMA to fail firmware sysfs fallback */ + ret = security_kernel_load_data(LOADING_FIRMWARE); + if (ret < 0) + return ret; + return fw_force_sysfs_fallback(opt_flags); }
Add an LSM hook prior to allowing firmware sysfs fallback loading. Signed-off-by: Mimi Zohar <zohar@linux.vnet.ibm.com> Cc: Luis R. Rodriguez <mcgrof@suse.com> Cc: David Howells <dhowells@redhat.com> Cc: Kees Cook <keescook@chromium.org> Changelog v4: - call new LSM security_kernel_arg hook Changelog v2: - call security_kernel_read_blob() - rename the READING_FIRMWARE_FALLBACK kernel_read_file_id enumeration to READING_FIRMWARE_FALLBACK_SYSFS. --- drivers/base/firmware_loader/fallback.c | 7 +++++++ 1 file changed, 7 insertions(+)