On Thu, Dec 29, 2022 at 12:28:14PM -0800, Guenter Roeck wrote: > On Thu, Dec 29, 2022 at 6:43 AM Julius Werner <[email protected]> wrote: > > > > I can confirm that this warning is a false positive, at least. We're > > intentionally copying bytes from beyond the end of the header > > structure in this case. > > > > I don't know what kind of kernel system detects this stuff at runtime > > and how to silence it. Probably need to add a void pointer cast or > > something? > > > > This is part of kernel hardening code. Kees Cook might know what to do about > it.
One could probably throw in casts, like this example did: 0d043351e5ba ext4: fix fortify warning in fs/ext4/fast_commit.c:1551 Or one could probably imitate this example, and insert an appropriate flexible array (possibly with yet another union?): b43088f30db1 s390/zcrypt: fix warning about field-spanning write Side mostly-unrelated note: coreboot_table_populate() doesn't do any bounds checking that the individual entry copies don't overflow the table buffer size. We're _probably_ not that interested in recovering from a malicious (or even buggy) Coreboot, but it does seem like an area of improvement. Brian > > Guenter > > > On Thu, Dec 29, 2022 at 11:46 AM Paul Menzel <[email protected]> wrote: > > > > > > Dear Linux folks, > > > > > > > > > Running Linux v6.2-rc1+ on a motherboard using coreboot as firmware, the > > > warning below is shown. > > > > > > ``` > > > [ 1.630244] ------------[ cut here ]------------ > > > [ 1.630249] memcpy: detected field-spanning write (size 168) of > > > single field "&device->entry" at > > > drivers/firmware/google/coreboot_table.c:103 (size 8) > > > [ 1.630299] WARNING: CPU: 1 PID: 150 at > > > drivers/firmware/google/coreboot_table.c:103 > > > coreboot_table_probe+0x1ea/0x210 [coreboot_table] [...] _______________________________________________ coreboot mailing list -- [email protected] To unsubscribe send an email to [email protected]
