6.12-stable review patch. If anyone has any objections, please let me know.
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From: Jan Kiszka jan.kiszka@siemens.com
[ Upstream commit c5e81e672699e0c5557b2b755cc8f7a69aa92bff ]
The communication buffer allocated by setup_mm_hdr() is later on passed to tee_shm_register_kernel_buf(). The latter expects those buffers to be contiguous pages, but setup_mm_hdr() just uses kmalloc(). That can cause various corruptions or BUGs, specifically since commit 9aec2fb0fd5e ("slab: allocate frozen pages"), though it was broken before as well.
Fix this by using alloc_pages_exact() instead of kmalloc().
Fixes: c44b6be62e8d ("efi: Add tee-based EFI variable driver") Signed-off-by: Jan Kiszka jan.kiszka@siemens.com Acked-by: Ilias Apalodimas ilias.apalodimas@linaro.org Acked-by: Sumit Garg sumit.garg@oss.qualcomm.com Signed-off-by: Ard Biesheuvel ardb@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/firmware/efi/stmm/tee_stmm_efi.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-)
diff --git a/drivers/firmware/efi/stmm/tee_stmm_efi.c b/drivers/firmware/efi/stmm/tee_stmm_efi.c index f741ca279052b..e15d11ed165ee 100644 --- a/drivers/firmware/efi/stmm/tee_stmm_efi.c +++ b/drivers/firmware/efi/stmm/tee_stmm_efi.c @@ -143,6 +143,10 @@ static efi_status_t mm_communicate(u8 *comm_buf, size_t payload_size) return var_hdr->ret_status; }
+#define COMM_BUF_SIZE(__payload_size) (MM_COMMUNICATE_HEADER_SIZE + \ + MM_VARIABLE_COMMUNICATE_SIZE + \ + (__payload_size)) + /** * setup_mm_hdr() - Allocate a buffer for StandAloneMM and initialize the * header data. @@ -173,9 +177,8 @@ static void *setup_mm_hdr(u8 **dptr, size_t payload_size, size_t func, return NULL; }
- comm_buf = kzalloc(MM_COMMUNICATE_HEADER_SIZE + - MM_VARIABLE_COMMUNICATE_SIZE + payload_size, - GFP_KERNEL); + comm_buf = alloc_pages_exact(COMM_BUF_SIZE(payload_size), + GFP_KERNEL | __GFP_ZERO); if (!comm_buf) { *ret = EFI_OUT_OF_RESOURCES; return NULL; @@ -239,7 +242,7 @@ static efi_status_t get_max_payload(size_t *size) */ *size -= 2; out: - kfree(comm_buf); + free_pages_exact(comm_buf, COMM_BUF_SIZE(payload_size)); return ret; }
@@ -282,7 +285,7 @@ static efi_status_t get_property_int(u16 *name, size_t name_size, memcpy(var_property, &smm_property->property, sizeof(*var_property));
out: - kfree(comm_buf); + free_pages_exact(comm_buf, COMM_BUF_SIZE(payload_size)); return ret; }
@@ -347,7 +350,7 @@ static efi_status_t tee_get_variable(u16 *name, efi_guid_t *vendor, memcpy(data, (u8 *)var_acc->name + var_acc->name_size, var_acc->data_size); out: - kfree(comm_buf); + free_pages_exact(comm_buf, COMM_BUF_SIZE(payload_size)); return ret; }
@@ -404,7 +407,7 @@ static efi_status_t tee_get_next_variable(unsigned long *name_size, memcpy(name, var_getnext->name, var_getnext->name_size);
out: - kfree(comm_buf); + free_pages_exact(comm_buf, COMM_BUF_SIZE(payload_size)); return ret; }
@@ -467,7 +470,7 @@ static efi_status_t tee_set_variable(efi_char16_t *name, efi_guid_t *vendor, ret = mm_communicate(comm_buf, payload_size); dev_dbg(pvt_data.dev, "Set Variable %s %d %lx\n", __FILE__, __LINE__, ret); out: - kfree(comm_buf); + free_pages_exact(comm_buf, COMM_BUF_SIZE(payload_size)); return ret; }
@@ -507,7 +510,7 @@ static efi_status_t tee_query_variable_info(u32 attributes, *max_variable_size = mm_query_info->max_variable_size;
out: - kfree(comm_buf); + free_pages_exact(comm_buf, COMM_BUF_SIZE(payload_size)); return ret; }