mirrors/linux
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git synced 2026-05-06 07:34:03 -04:00
Code Issues Packages Projects Releases Wiki Activity

KVM: arm64: Add memory length checks and remove inline in do_ffa_mem_xfer

Browse Source 
When we share memory through FF-A and the description of the buffers
exceeds the size of the mapped buffer, the fragmentation API is used.
The fragmentation API allows specifying chunks of descriptors in subsequent
FF-A fragment calls and no upper limit has been established for this.
The entire memory region transferred is identified by a handle which can be
used to reclaim the transferred memory.
To be able to reclaim the memory, the description of the buffers has to fit
in the ffa_desc_buf.
Add a bounds check on the FF-A sharing path to prevent the memory reclaim
from failing.

Also do_ffa_mem_xfer() does not need __always_inline, except for the
BUILD_BUG_ON() aspect, which gets moved to a macro.

[maz: fixed the BUILD_BUG_ON() breakage with LLVM, thanks to Wei-Lin Chang
 for the timely report]

Fixes: 634d90cf0a ("KVM: arm64: Handle FFA_MEM_LEND calls from the host")
Cc: stable@vger.kernel.org
Reviewed-by: Sebastian Ene <sebastianene@google.com>
Signed-off-by: Snehal Koukuntla <snehalreddy@google.com>
Reviewed-by: Oliver Upton <oliver.upton@linux.dev>
Link: https://lore.kernel.org/r/20240909180154.3267939-1-snehalreddy@google.com
Signed-off-by: Marc Zyngier <maz@kernel.org>
This commit is contained in:
Snehal Koukuntla
2024-09-09 18:01:54 +00:00
committed by Marc Zyngier
parent e0b7de4fd1
commit f26a525b77
1 changed files with 15 additions and 6 deletions
Download Patch File Download Diff File Expand all files Collapse all files

21
arch/arm64/kvm/hyp/nvhe/ffa.c
View File

@@ -426,9 +426,9 @@ static void do_ffa_mem_frag_tx(struct arm_smccc_res *res,
return;
}
static __always_inline void do_ffa_mem_xfer(const u64 func_id,
struct arm_smccc_res *res,
struct kvm_cpu_context *ctxt)
static void __do_ffa_mem_xfer(const u64 func_id,
struct arm_smccc_res *res,
struct kvm_cpu_context *ctxt)
{
DECLARE_REG(u32, len, ctxt, 1);
DECLARE_REG(u32, fraglen, ctxt, 2);
@@ -440,9 +440,6 @@ static __always_inline void do_ffa_mem_xfer(const u64 func_id,
u32 offset, nr_ranges;
int ret = 0;
BUILD_BUG_ON(func_id != FFA_FN64_MEM_SHARE &&
func_id != FFA_FN64_MEM_LEND);
if (addr_mbz || npages_mbz || fraglen > len ||
fraglen > KVM_FFA_MBOX_NR_PAGES * PAGE_SIZE) {
ret = FFA_RET_INVALID_PARAMETERS;
@@ -461,6 +458,11 @@ static __always_inline void do_ffa_mem_xfer(const u64 func_id,
goto out_unlock;
}
if (len > ffa_desc_buf.len) {
ret = FFA_RET_NO_MEMORY;
goto out_unlock;
}
buf = hyp_buffers.tx;
memcpy(buf, host_buffers.tx, fraglen);
@@ -512,6 +514,13 @@ static __always_inline void do_ffa_mem_xfer(const u64 func_id,
goto out_unlock;
}
#define do_ffa_mem_xfer(fid, res, ctxt) \
do { \
BUILD_BUG_ON((fid) != FFA_FN64_MEM_SHARE && \
(fid) != FFA_FN64_MEM_LEND); \
__do_ffa_mem_xfer((fid), (res), (ctxt)); \
} while (0);
static void do_ffa_mem_reclaim(struct arm_smccc_res *res,
struct kvm_cpu_context *ctxt)
{