5.4-stable review patch. If anyone has any objections, please let me know.
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From: Bjorn Andersson bjorn.andersson@oss.qualcomm.com
commit 25daf9af0ac1bf12490b723b5efaf8dcc85980bc upstream.
Firmware that doesn't provide section headers leave both e_shentsize and e_shnum 0, which obvious isn't compatible with the newly introduced stricter checks.
Make the section-related checks conditional on either of these values being non-zero.
Fixes: 9f9967fed9d0 ("soc: qcom: mdt_loader: Ensure we don't read past the ELF header") Reported-by: Val Packett val@packett.cool Closes: https://lore.kernel.org/all/ece307c3-7d65-440f-babd-88cf9705b908@packett.coo... Reported-by: Neil Armstrong neil.armstrong@linaro.org Closes: https://lore.kernel.org/all/aec9cd03-6fc2-4dc8-b937-8b7cf7bf4128@linaro.org/ Signed-off-by: Bjorn Andersson bjorn.andersson@oss.qualcomm.com Fixes: 9f35ab0e53cc ("soc: qcom: mdt_loader: Fix error return values in mdt_header_valid()") Tested-by: Neil Armstrong neil.armstrong@linaro.org # on SM8650-QRD Reviewed-by: Dmitry Baryshkov dmitry.baryshkov@oss.qualcomm.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250730-mdt-loader-shentsize-zero-v1-1-04f4318622... Signed-off-by: Bjorn Andersson andersson@kernel.org Cc: Yongqin Liu yongqin.liu@linaro.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/soc/qcom/mdt_loader.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-)
--- a/drivers/soc/qcom/mdt_loader.c +++ b/drivers/soc/qcom/mdt_loader.c @@ -39,12 +39,14 @@ static bool mdt_header_valid(const struc if (phend > fw->size) return false;
- if (ehdr->e_shentsize != sizeof(struct elf32_shdr)) - return false; + if (ehdr->e_shentsize || ehdr->e_shnum) { + if (ehdr->e_shentsize != sizeof(struct elf32_shdr)) + return false;
- shend = size_add(size_mul(sizeof(struct elf32_shdr), ehdr->e_shnum), ehdr->e_shoff); - if (shend > fw->size) - return false; + shend = size_add(size_mul(sizeof(struct elf32_shdr), ehdr->e_shnum), ehdr->e_shoff); + if (shend > fw->size) + return false; + }
return true; }