FAILED: patch "[PATCH] KVM: arm64: Check the untrusted offset in FF-A memory share" failed to apply to 6.6-stable tree
Subsystems (3)
[email protected]
maintainerThe patch below does not apply to the 6.6-stable tree.
If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <[email protected]>.
To reproduce the conflict and resubmit, you may use the following commands:
git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.6.y
git checkout FETCH_HEAD
git cherry-pick -x 103e17aac09cdd358133f9e00998b75d6c1f1518
# <resolve conflicts, build, test, etc.>
git commit -s
git send-email --to '<[email protected]>' --in-reply-to '2025112429-pasture-geometry-591b@gregkh' --subject-prefix 'PATCH 6.6.y' HEAD^..
Possible dependencies:
thanks,
greg k-h
------------------ original commit in Linus's tree ------------------
From 103e17aac09cdd358133f9e00998b75d6c1f1518 Mon Sep 17 00:00:00 2001
From: Sebastian Ene <[email protected]>
Date: Fri, 17 Oct 2025 07:57:10 +0000
Subject: [PATCH] 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.
arch/arm64/kvm/hyp/nvhe/ffa.c +7 -2
@@ -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; }
Sasha Levin
maintainerPATCH 1/1 KVM: arm64: Check the untrusted offset in FF-A memory share
From: Sebastian Ene <[email protected]>
[ Upstream commit 103e17aac09cdd358133f9e00998b75d6c1f1518 ]
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.
--- arch/arm64/kvm/hyp/nvhe/ffa.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)
arch/arm64/kvm/hyp/nvhe/ffa.c +7 -2
@@ -425,7 +425,7 @@ static void __do_ffa_mem_xfer(const u64 func_id,DECLARE_REG (u32, npages_mbz, ctxt,4 );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 ||
@@ -460,7 +460,12 @@ 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; }
Signature · 1 line
2.51.0
Greg KH
maintainerRe: [PATCH 6.6.y] KVM: arm64: Check the untrusted offset in FF-A memory share
Quoted 32 lines · Sasha Levin
From: Sebastian Ene <[email protected]>
[ Upstream commit
103e17aac09cdd358133f9e00998b75d6c1f1518]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 <[email protected]>Acked-by Will Deacon <[email protected]>Signed-off-by Marc Zyngier <[email protected]>Signed-off-by Sasha Levin <[email protected]>--- arch/arm64/kvm/hyp/nvhe/ffa.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)arch/arm64/kvm/hyp/nvhe/ffa.c +1
-1@@ -425,7 +425,7 @@ static void __do_ffa_mem_xfer(const u64 func_id,DECLARE_REG (u32, npages_mbz, ctxt,4 );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 ||
arch/arm64/kvm/hyp/nvhe/ffa.c static void __do_ffa_mem_xfer(const u64 func_id, · line 466
Quoted 8 lines
arch/arm64/kvm/hyp/nvhe/ffa.c +4
-1@@ -460,7 +460,12 @@ 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; + }
I was told that a "straight" backport like this was not correct, so we need a "better" one :(
Sebastian, can you provide the correct backport for 6.6.y please?
thanks,
greg k-h
Re: [PATCH 6.6.y] KVM: arm64: Check the untrusted offset in FF-A memory share
Quoted 36 lines · Greg KH
Quoted 35 lines · Sasha Levin
From: Sebastian Ene <[email protected]>
[ Upstream commit
103e17aac09cdd358133f9e00998b75d6c1f1518]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 <[email protected]>Acked-by Will Deacon <[email protected]>Signed-off-by Marc Zyngier <[email protected]>Signed-off-by Sasha Levin <[email protected]>--- arch/arm64/kvm/hyp/nvhe/ffa.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)arch/arm64/kvm/hyp/nvhe/ffa.c +1
-1@@ -425,7 +425,7 @@ static void __do_ffa_mem_xfer(const u64 func_id,DECLARE_REG (u32, npages_mbz, ctxt,4 );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 ||@@ -460,7 +460,12 @@ static void __do_ffa_mem_xfer(const u64 func_id, goto out_unlock; }
Quoted 5 lines
arch/arm64/kvm/hyp/nvhe/ffa.c static void __do_ffa_mem_xfer(const u64 func_id, · line 466
Quoted 5 lines
arch/arm64/kvm/hyp/nvhe/ffa.c +4
-1-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; + }
hello Greg,
Quoted 6 lines
I was told that a "straight" backport like this was not correct, so we need a "better" one :(
Sebastian, can you provide the correct backport for 6.6.y please?
I think Sasha's patch is doing the right thing. Sasha thanks for posting it so fast.
I looked up the other faild patches on stable and the reason why the patch doesn't apply is because we don't have the FF-A proxy inthe following versions:
- 5.4, 5.10, 5.15, 6.1
Quoted 3 lines
thanks,
greg k-h
thanks,
Sebastian
Sasha Levin
maintainerRe: [PATCH 6.6.y] KVM: arm64: Check the untrusted offset in FF-A memory share
Quoted 46 lines · Sebastian Ene
Quoted 36 lines · Greg KH
Quoted 35 lines · Sasha Levin
From: Sebastian Ene <[email protected]>
[ Upstream commit
103e17aac09cdd358133f9e00998b75d6c1f1518]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 <[email protected]>Acked-by Will Deacon <[email protected]>Signed-off-by Marc Zyngier <[email protected]>Signed-off-by Sasha Levin <[email protected]>--- arch/arm64/kvm/hyp/nvhe/ffa.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)arch/arm64/kvm/hyp/nvhe/ffa.c +1
-1@@ -425,7 +425,7 @@ static void __do_ffa_mem_xfer(const u64 func_id,DECLARE_REG (u32, npages_mbz, ctxt,4 );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 ||@@ -460,7 +460,12 @@ static void __do_ffa_mem_xfer(const u64 func_id, goto out_unlock; }Quoted 5 lines
arch/arm64/kvm/hyp/nvhe/ffa.c static void __do_ffa_mem_xfer(const u64 func_id, · line 466
Quoted 5 lines
arch/arm64/kvm/hyp/nvhe/ffa.c +4
-1-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; + }hello Greg,
Quoted 1 line
Quoted 8 lines
Quoted 5 lines
I was told that a "straight" backport like this was not correct, so we need a "better" one :(
Sebastian, can you provide the correct backport for 6.6.y please?
I think Sasha's patch is doing the right thing. Sasha thanks for posting it so fast.
For the record, my patch just adjusted line numbers a bit, there were no conflicts.
Quoted 3 lines
I looked up the other faild patches on stable and the reason why the patch doesn't apply is because we don't have the FF-A proxy inthe following versions:
- 5.4, 5.10, 5.15, 6.1
Right, I noticed that and assumed that this isn't needed on those older trees.
Signature · 2 lines
Thanks, Sasha
Greg KH
maintainerRe: [PATCH 6.6.y] KVM: arm64: Check the untrusted offset in FF-A memory share
In reply to Sebastian EneQuoted 46 lines · Sebastian Ene
Quoted 36 lines · Greg KH
Quoted 35 lines · Sasha Levin
From: Sebastian Ene <[email protected]>
[ Upstream commit
103e17aac09cdd358133f9e00998b75d6c1f1518]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 <[email protected]>Acked-by Will Deacon <[email protected]>Signed-off-by Marc Zyngier <[email protected]>Signed-off-by Sasha Levin <[email protected]>--- arch/arm64/kvm/hyp/nvhe/ffa.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)arch/arm64/kvm/hyp/nvhe/ffa.c +1
-1@@ -425,7 +425,7 @@ static void __do_ffa_mem_xfer(const u64 func_id,DECLARE_REG (u32, npages_mbz, ctxt,4 );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 ||@@ -460,7 +460,12 @@ static void __do_ffa_mem_xfer(const u64 func_id, goto out_unlock; }Quoted 5 lines
arch/arm64/kvm/hyp/nvhe/ffa.c static void __do_ffa_mem_xfer(const u64 func_id, · line 466
Quoted 5 lines
arch/arm64/kvm/hyp/nvhe/ffa.c +4
-1-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; + }hello Greg,
Quoted 1 line
Quoted 8 lines
Quoted 5 lines
I was told that a "straight" backport like this was not correct, so we need a "better" one :(
Sebastian, can you provide the correct backport for 6.6.y please?
I think Sasha's patch is doing the right thing. Sasha thanks for posting it so fast.
Then why is the backport that is in the android 6.6.y kernel branches different from this one? Which one is "correct"?
thanks,
greg k-h
Re: [PATCH 6.6.y] KVM: arm64: Check the untrusted offset in FF-A memory share
Quoted 50 lines · Greg KH
Quoted 49 lines · Sebastian Ene
Quoted 36 lines · Greg KH
Quoted 35 lines · Sasha Levin
From: Sebastian Ene <[email protected]>
[ Upstream commit
103e17aac09cdd358133f9e00998b75d6c1f1518]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 <[email protected]>Acked-by Will Deacon <[email protected]>Signed-off-by Marc Zyngier <[email protected]>Signed-off-by Sasha Levin <[email protected]>--- arch/arm64/kvm/hyp/nvhe/ffa.c | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-)arch/arm64/kvm/hyp/nvhe/ffa.c +1
-1@@ -425,7 +425,7 @@ static void __do_ffa_mem_xfer(const u64 func_id,DECLARE_REG (u32, npages_mbz, ctxt,4 );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 ||@@ -460,7 +460,12 @@ static void __do_ffa_mem_xfer(const u64 func_id, goto out_unlock; }Quoted 5 lines
arch/arm64/kvm/hyp/nvhe/ffa.c static void __do_ffa_mem_xfer(const u64 func_id, · line 466
Quoted 5 lines
arch/arm64/kvm/hyp/nvhe/ffa.c +4
-1-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; + }hello Greg,
Quoted 4 lines
I was told that a "straight" backport like this was not correct, so we need a "better" one :(
Quoted 9 lines
Quoted 5 lines
Quoted 2 lines
Sebastian, can you provide the correct backport for 6.6.y please?
I think Sasha's patch is doing the right thing. Sasha thanks for posting it so fast.
Then why is the backport that is in the android 6.6.y kernel branches different from this one? Which one is "correct"?
Right, there is a slighly difference between the two which doesn't affect the correctness in any way. The one from the android 6.6 branch uses ffa_to_smccc_error call to post the return code instead of simply setting the ret code an returning. The correct one is the one from Sasha.
The one from the android 6.6 tree is labeled incorrectly FROMGIT, it should be BACKPORT: FROMGIT: because it has this small difference. I hope this clarifies it.
Quoted 3 lines
thanks,
greg k-h
Thanks,
Sebastian