diff options
| author | Sebastian Ene <sebastianene@google.com> | 2025-10-17 07:57:10 +0000 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2025-10-30 16:14:58 +0000 |
| commit | 103e17aac09cdd358133f9e00998b75d6c1f1518 (patch) | |
| tree | 4354f94dff17ba18a2c8204374c68b9842826876 | |
| parent | f71f7afd0a0cd3f044cd2f8aba71a1a7229df762 (diff) | |
KVM: arm64: Check the untrusted offset in FF-A memory share
Verify the offset to prevent OOB access in the hypervisor
FF-A buffer in case an untrusted large enough value
[U32_MAX - sizeof(struct ffa_composite_mem_region) + 1, U32_MAX]
is set from the host kernel.
Signed-off-by: Sebastian Ene <sebastianene@google.com>
Acked-by: Will Deacon <will@kernel.org>
Link: https://patch.msgid.link/20251017075710.2605118-1-sebastianene@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
| -rw-r--r-- | arch/arm64/kvm/hyp/nvhe/ffa.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/arch/arm64/kvm/hyp/nvhe/ffa.c b/arch/arm64/kvm/hyp/nvhe/ffa.c index 4e16f9b96f63..58b7d0c477d7 100644 --- a/arch/arm64/kvm/hyp/nvhe/ffa.c +++ b/arch/arm64/kvm/hyp/nvhe/ffa.c @@ -479,7 +479,7 @@ static void __do_ffa_mem_xfer(const u64 func_id, struct ffa_mem_region_attributes *ep_mem_access; struct ffa_composite_mem_region *reg; struct ffa_mem_region *buf; - u32 offset, nr_ranges; + u32 offset, nr_ranges, checked_offset; int ret = 0; if (addr_mbz || npages_mbz || fraglen > len || @@ -516,7 +516,12 @@ static void __do_ffa_mem_xfer(const u64 func_id, goto out_unlock; } - if (fraglen < offset + sizeof(struct ffa_composite_mem_region)) { + if (check_add_overflow(offset, sizeof(struct ffa_composite_mem_region), &checked_offset)) { + ret = FFA_RET_INVALID_PARAMETERS; + goto out_unlock; + } + + if (fraglen < checked_offset) { ret = FFA_RET_INVALID_PARAMETERS; goto out_unlock; } |