2024-01-31 09:43:16

by Auditya Bhattaram

Subject: [PATCH] soc: qcom: mdt_loader: Add Upperbounds check for program header access

hash_index is evaluated by looping phdrs till QCOM_MDT_TYPE_HASH
is found. Add an upperbound check to phdrs to access within elf size.

Signed-off-by: Auditya Bhattaram <[email protected]>
---
drivers/soc/qcom/mdt_loader.c | 3 +++
1 file changed, 3 insertions(+)

diff --git a/drivers/soc/qcom/mdt_loader.c b/drivers/soc/qcom/mdt_loader.c
index 6f177e46fa0f..fee86317ad83 100644
--- a/drivers/soc/qcom/mdt_loader.c
+++ b/drivers/soc/qcom/mdt_loader.c
@@ -145,6 +145,9 @@ void *qcom_mdt_read_metadata(const struct firmware *fw, size_t *data_len,
if (phdrs[0].p_type == PT_LOAD)
return ERR_PTR(-EINVAL);

+ if (((size_t)(phdrs + ehdr->e_phnum)) > ((size_t)ehdr + fw->size))
+ return ERR_PTR(-EINVAL);
+
for (i = 1; i < ehdr->e_phnum; i++) {
if ((phdrs[i].p_flags & QCOM_MDT_TYPE_MASK) == QCOM_MDT_TYPE_HASH) {
hash_segment = i;
--
2.17.1

2024-02-01 14:50:49

by Konrad Dybcio

Subject: Re: [PATCH] soc: qcom: mdt_loader: Add Upperbounds check for program header access

On 31.01.2024 10:42, Auditya Bhattaram wrote:
> hash_index is evaluated by looping phdrs till QCOM_MDT_TYPE_HASH
> is found. Add an upperbound check to phdrs to access within elf size.
>
> Signed-off-by: Auditya Bhattaram <[email protected]>
> ---

Could you print an error when this happens? There's a lot of EINVALs
in the MDT loader codepaths, but you never know which one fired..

Konrad

2024-02-02 06:38:11

by Auditya Bhattaram

Subject: Re: [PATCH] soc: qcom: mdt_loader: Add Upperbounds check for program header access

On 2/1/2024 8:20 PM, Konrad Dybcio wrote:
> On 31.01.2024 10:42, Auditya Bhattaram wrote:
>> hash_index is evaluated by looping phdrs till QCOM_MDT_TYPE_HASH
>> is found. Add an upperbound check to phdrs to access within elf size.
>>
>> Signed-off-by: Auditya Bhattaram <[email protected]>
>> ---
>
> Could you print an error when this happens? There's a lot of EINVALs
> in the MDT loader codepaths, but you never know which one fired..
>
> Konrad

Sure, will add error prints