| Message ID | 20200724213640.389191-4-keescook@chromium.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Introduce partial kernel_read_file() support | expand |
On Fri, Jul 24, 2020 at 02:36:24PM -0700, Kees Cook wrote: > The EFI platform firmware fallback would clobber any pre-allocated > buffers. Instead, correctly refuse to reallocate when too small (as > already done in the sysfs fallback), or perform allocation normally > when needed. > > Fixes: e4c2c0ff00ec ("firmware: Add new platform fallback mechanism and firm ware_request_platform()") "firmware_request_platform()" :)
On Sat, Jul 25, 2020 at 12:07:00PM +0200, Greg Kroah-Hartman wrote: > On Fri, Jul 24, 2020 at 02:36:24PM -0700, Kees Cook wrote: > > The EFI platform firmware fallback would clobber any pre-allocated > > buffers. Instead, correctly refuse to reallocate when too small (as > > already done in the sysfs fallback), or perform allocation normally > > when needed. > > > > Fixes: e4c2c0ff00ec ("firmware: Add new platform fallback mechanism and firm ware_request_platform()") > > "firmware_request_platform()" :) Weird... I'm not sure where that mangling happened. Perhaps a bad cut/paste at 80 columns? Hmpf; thanks for catching. I've updated it on my end (I assume you fixed this manually, though?) Thanks!
On Sat, Jul 25, 2020 at 08:50:33AM -0700, Kees Cook wrote: > On Sat, Jul 25, 2020 at 12:07:00PM +0200, Greg Kroah-Hartman wrote: > > On Fri, Jul 24, 2020 at 02:36:24PM -0700, Kees Cook wrote: > > > The EFI platform firmware fallback would clobber any pre-allocated > > > buffers. Instead, correctly refuse to reallocate when too small (as > > > already done in the sysfs fallback), or perform allocation normally > > > when needed. > > > > > > Fixes: e4c2c0ff00ec ("firmware: Add new platform fallback mechanism and firm ware_request_platform()") > > > > "firmware_request_platform()" :) > > Weird... I'm not sure where that mangling happened. Perhaps a bad > cut/paste at 80 columns? Hmpf; thanks for catching. I've updated it on > my end (I assume you fixed this manually, though?) Yes, I fixed it up already, no worries. greg k-h
diff --git a/drivers/base/firmware_loader/fallback_platform.c b/drivers/base/firmware_loader/fallback_platform.c index cdd2c9a9f38a..685edb7dd05a 100644 --- a/drivers/base/firmware_loader/fallback_platform.c +++ b/drivers/base/firmware_loader/fallback_platform.c @@ -25,7 +25,10 @@ int firmware_fallback_platform(struct fw_priv *fw_priv, u32 opt_flags) if (rc) return rc; /* rc == -ENOENT when the fw was not found */ - fw_priv->data = vmalloc(size); + if (fw_priv->data && size > fw_priv->allocated_size) + return -ENOMEM; + if (!fw_priv->data) + fw_priv->data = vmalloc(size); if (!fw_priv->data) return -ENOMEM;
The EFI platform firmware fallback would clobber any pre-allocated buffers. Instead, correctly refuse to reallocate when too small (as already done in the sysfs fallback), or perform allocation normally when needed. Fixes: e4c2c0ff00ec ("firmware: Add new platform fallback mechanism and firm ware_request_platform()") Cc: stable@vger.kernel.org Acked-by: Scott Branden <scott.branden@broadcom.com> Signed-off-by: Kees Cook <keescook@chromium.org> --- To aid in backporting, this change is made before moving kernel_read_file() to separate header/source files. --- drivers/base/firmware_loader/fallback_platform.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-)