| Message ID | 20240213080010.16924-1-quic_audityab@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v4] soc: qcom: mdt_loader: Add Upperbounds check for program header access | expand |
On 2/14/2024 11:27 AM, Auditya Bhattaram wrote: > > > On 2/14/2024 11:12 AM, Bjorn Andersson wrote: >> On Tue, Feb 13, 2024 at 01:30:10PM +0530, 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. >>> >> >> How is this compatible with what is being observed on SM8450 and >> implemented in commit 8bd42e2341a7 ("soc: qcom: mdt_loader: Allow hash >> segment to be split out"? >> >> Regards, >> Bjorn >> > > Calculating hash_index is introduced with this commit 8bd42e2341a7 > ("soc: qcom: mdt_loader: Allow hash segment to be split out" > > for (i = 1; i < ehdr->e_phnum; i++) { > if ((phdrs[i].p_flags & QCOM_MDT_TYPE_MASK) ... > > I'm trying to add an upper bound for this access "phdrs[i]" > Any further questions on this Bjorn. >>> Fixes: 64fb5eb87d58 ("soc: qcom: mdt_loader: Allow hash to reside in >>> any segment") >>> Cc: <stable@vger.kernel.org> >>> Signed-off-by: Auditya Bhattaram <quic_audityab@quicinc.com> >>> Acked-by: Mukesh Ojha <quic_mojha@quicinc.com> >>> --- >>> Changes in v4: >>> - Added additional prints incase of Invalid access. >>> Link to v3 >>> https://lore.kernel.org/stable/1c91c653-cebe-4407-bdd6-cfc73b64c0fb@quicinc.com >>> Link to v2 >>> https://lore.kernel.org/linux-arm-msm/9773d189-c896-d5c5-804c-e086c24987b4@quicinc.com/T/#t >>> Link to v1 >>> https://lore.kernel.org/linux-arm-msm/5d7a3b97-d840-4863-91a0-32c1d8e7532f@linaro.org/T/#t >>> --- >>> drivers/soc/qcom/mdt_loader.c | 7 +++++++ >>> 1 file changed, 7 insertions(+) >>> >>> diff --git a/drivers/soc/qcom/mdt_loader.c >>> b/drivers/soc/qcom/mdt_loader.c >>> index 6f177e46fa0f..1a79a7bba468 100644 >>> --- a/drivers/soc/qcom/mdt_loader.c >>> +++ b/drivers/soc/qcom/mdt_loader.c >>> @@ -145,6 +143,13 @@ 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)) { >>> + dev_err(dev, >>> + "Invalid phdrs access for fw: %s, e_phnum: %u, fw->size: >>> %zu\n", >>> + fw_name, ehdr->e_phnum, 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 >>>
diff --git a/drivers/soc/qcom/mdt_loader.c b/drivers/soc/qcom/mdt_loader.c index 6f177e46fa0f..1a79a7bba468 100644 --- a/drivers/soc/qcom/mdt_loader.c +++ b/drivers/soc/qcom/mdt_loader.c @@ -145,6 +143,13 @@ 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)) { + dev_err(dev, + "Invalid phdrs access for fw: %s, e_phnum: %u, fw->size: %zu\n", + fw_name, ehdr->e_phnum, 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;
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. Fixes: 64fb5eb87d58 ("soc: qcom: mdt_loader: Allow hash to reside in any segment") Cc: <stable@vger.kernel.org> Signed-off-by: Auditya Bhattaram <quic_audityab@quicinc.com> Acked-by: Mukesh Ojha <quic_mojha@quicinc.com> --- Changes in v4: - Added additional prints incase of Invalid access. Link to v3 https://lore.kernel.org/stable/1c91c653-cebe-4407-bdd6-cfc73b64c0fb@quicinc.com Link to v2 https://lore.kernel.org/linux-arm-msm/9773d189-c896-d5c5-804c-e086c24987b4@quicinc.com/T/#t Link to v1 https://lore.kernel.org/linux-arm-msm/5d7a3b97-d840-4863-91a0-32c1d8e7532f@linaro.org/T/#t --- drivers/soc/qcom/mdt_loader.c | 7 +++++++ 1 file changed, 7 insertions(+) -- 2.17.1