From 26d0fba29c96241de8a9d16f045b1de49875884c Mon Sep 17 00:00:00 2001 From: Leonard Crestez Date: Thu, 20 Feb 2020 18:10:01 +0200 Subject: firmware: imx: scu: Ensure sequential TX SCU requires that all messages words are written sequentially but linux MU driver implements multiple independent channels for each register so ordering between different channels must be ensured by SCU API interface. Wait for tx_done before every send to ensure that no queueing happens at the mailbox channel level. Fixes: edbee095fafb ("firmware: imx: add SCU firmware driver support") Signed-off-by: Leonard Crestez Cc: Reviewed-by: Peng Fan Reviewed-by:: Oleksij Rempel Signed-off-by: Shawn Guo --- drivers/firmware/imx/imx-scu.c | 27 +++++++++++++++++++++++++++ 1 file changed, 27 insertions(+) (limited to 'drivers/firmware') diff --git a/drivers/firmware/imx/imx-scu.c b/drivers/firmware/imx/imx-scu.c index 03b43b7a6d1d..f71eaa5bf52d 100644 --- a/drivers/firmware/imx/imx-scu.c +++ b/drivers/firmware/imx/imx-scu.c @@ -29,6 +29,7 @@ struct imx_sc_chan { struct mbox_client cl; struct mbox_chan *ch; int idx; + struct completion tx_done; }; struct imx_sc_ipc { @@ -100,6 +101,14 @@ int imx_scu_get_handle(struct imx_sc_ipc **ipc) } EXPORT_SYMBOL(imx_scu_get_handle); +/* Callback called when the word of a message is ack-ed, eg read by SCU */ +static void imx_scu_tx_done(struct mbox_client *cl, void *mssg, int r) +{ + struct imx_sc_chan *sc_chan = container_of(cl, struct imx_sc_chan, cl); + + complete(&sc_chan->tx_done); +} + static void imx_scu_rx_callback(struct mbox_client *c, void *msg) { struct imx_sc_chan *sc_chan = container_of(c, struct imx_sc_chan, cl); @@ -149,6 +158,19 @@ static int imx_scu_ipc_write(struct imx_sc_ipc *sc_ipc, void *msg) for (i = 0; i < hdr->size; i++) { sc_chan = &sc_ipc->chans[i % 4]; + + /* + * SCU requires that all messages words are written + * sequentially but linux MU driver implements multiple + * independent channels for each register so ordering between + * different channels must be ensured by SCU API interface. + * + * Wait for tx_done before every send to ensure that no + * queueing happens at the mailbox channel level. + */ + wait_for_completion(&sc_chan->tx_done); + reinit_completion(&sc_chan->tx_done); + ret = mbox_send_message(sc_chan->ch, &data[i]); if (ret < 0) return ret; @@ -247,6 +269,11 @@ static int imx_scu_probe(struct platform_device *pdev) cl->knows_txdone = true; cl->rx_callback = imx_scu_rx_callback; + /* Initial tx_done completion as "done" */ + cl->tx_done = imx_scu_tx_done; + init_completion(&sc_chan->tx_done); + complete(&sc_chan->tx_done); + sc_chan->sc_ipc = sc_ipc; sc_chan->idx = i % 4; sc_chan->ch = mbox_request_channel_byname(cl, chan_name); -- cgit v1.2.3 From 1e6a4eba693ac72e6f91b4252458c933110e5f4c Mon Sep 17 00:00:00 2001 From: Leonard Crestez Date: Thu, 20 Feb 2020 18:29:34 +0200 Subject: firmware: imx: misc: Align imx sc msg structs to 4 The imx SC api strongly assumes that messages are composed out of 4-bytes words but some of our message structs have odd sizeofs. This produces many oopses with CONFIG_KASAN=y: BUG: KASAN: stack-out-of-bounds in imx_mu_send_data+0x108/0x1f0 It shouldn't cause an issues in normal use because these structs are always allocated on the stack. Fixes: 15e1f2bc8b3b ("firmware: imx: add misc svc support") Signed-off-by: Leonard Crestez Signed-off-by: Shawn Guo --- drivers/firmware/imx/misc.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/imx/misc.c b/drivers/firmware/imx/misc.c index 4b56a587dacd..6a21ff942f82 100644 --- a/drivers/firmware/imx/misc.c +++ b/drivers/firmware/imx/misc.c @@ -16,7 +16,7 @@ struct imx_sc_msg_req_misc_set_ctrl { u32 ctrl; u32 val; u16 resource; -} __packed; +} __packed __aligned(4); struct imx_sc_msg_req_cpu_start { struct imx_sc_rpc_msg hdr; @@ -30,12 +30,12 @@ struct imx_sc_msg_req_misc_get_ctrl { struct imx_sc_rpc_msg hdr; u32 ctrl; u16 resource; -} __packed; +} __packed __aligned(4); struct imx_sc_msg_resp_misc_get_ctrl { struct imx_sc_rpc_msg hdr; u32 val; -} __packed; +} __packed __aligned(4); /* * This function sets a miscellaneous control value. -- cgit v1.2.3 From 7c1a1c814ccc858633c761951c2546041202b24e Mon Sep 17 00:00:00 2001 From: Leonard Crestez Date: Thu, 20 Feb 2020 18:29:35 +0200 Subject: firmware: imx: scu-pd: Align imx sc msg structs to 4 The imx SC api strongly assumes that messages are composed out of 4-bytes words but some of our message structs have odd sizeofs. This produces many oopses with CONFIG_KASAN=y. Fix by marking with __aligned(4). Fixes: c800cd7824bd ("firmware: imx: add SCU power domain driver") Signed-off-by: Leonard Crestez Signed-off-by: Shawn Guo --- drivers/firmware/imx/scu-pd.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/imx/scu-pd.c b/drivers/firmware/imx/scu-pd.c index b556612207e5..af3ae0087de4 100644 --- a/drivers/firmware/imx/scu-pd.c +++ b/drivers/firmware/imx/scu-pd.c @@ -61,7 +61,7 @@ struct imx_sc_msg_req_set_resource_power_mode { struct imx_sc_rpc_msg hdr; u16 resource; u8 mode; -} __packed; +} __packed __aligned(4); #define IMX_SCU_PD_NAME_SIZE 20 struct imx_sc_pm_domain { -- cgit v1.2.3 From f5bfeff44612d304deb100065a9f712309dc2783 Mon Sep 17 00:00:00 2001 From: Leonard Crestez Date: Thu, 20 Feb 2020 18:29:36 +0200 Subject: firmware: imx: Align imx_sc_msg_req_cpu_start to 4 The imx SC api strongly assumes that messages are composed out of 4-bytes words but some of our message structs have odd sizeofs. This produces many oopses with CONFIG_KASAN=y. Fix by marking with __aligned(4). Fixes: d90bf296ae18 ("firmware: imx: Add support to start/stop a CPU") Signed-off-by: Leonard Crestez Signed-off-by: Shawn Guo --- drivers/firmware/imx/misc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/imx/misc.c b/drivers/firmware/imx/misc.c index 6a21ff942f82..d073cb3ce699 100644 --- a/drivers/firmware/imx/misc.c +++ b/drivers/firmware/imx/misc.c @@ -24,7 +24,7 @@ struct imx_sc_msg_req_cpu_start { u32 address_lo; u16 resource; u8 enable; -} __packed; +} __packed __aligned(4); struct imx_sc_msg_req_misc_get_ctrl { struct imx_sc_rpc_msg hdr; -- cgit v1.2.3 From be36f9e7517e17810ec369626a128d7948942259 Mon Sep 17 00:00:00 2001 From: "Jason A. Donenfeld" Date: Fri, 21 Feb 2020 09:48:49 +0100 Subject: efi: READ_ONCE rng seed size before munmap This function is consistent with using size instead of seed->size (except for one place that this patch fixes), but it reads seed->size without using READ_ONCE, which means the compiler might still do something unwanted. So, this commit simply adds the READ_ONCE wrapper. Fixes: 636259880a7e ("efi: Add support for seeding the RNG from a UEFI ...") Signed-off-by: Jason A. Donenfeld Signed-off-by: Ard Biesheuvel Signed-off-by: Ingo Molnar Cc: linux-efi@vger.kernel.org Cc: Ingo Molnar Cc: Thomas Gleixner Link: https://lore.kernel.org/r/20200217123354.21140-1-Jason@zx2c4.com Link: https://lore.kernel.org/r/20200221084849.26878-5-ardb@kernel.org --- drivers/firmware/efi/efi.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 621220ab3d0e..21ea99f65113 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -552,7 +552,7 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz, seed = early_memremap(efi.rng_seed, sizeof(*seed)); if (seed != NULL) { - size = seed->size; + size = READ_ONCE(seed->size); early_memunmap(seed, sizeof(*seed)); } else { pr_err("Could not map UEFI random seed!\n"); @@ -562,7 +562,7 @@ int __init efi_config_parse_tables(void *config_tables, int count, int sz, sizeof(*seed) + size); if (seed != NULL) { pr_notice("seeding entropy pool\n"); - add_bootloader_randomness(seed->bits, seed->size); + add_bootloader_randomness(seed->bits, size); early_memunmap(seed, sizeof(*seed) + size); } else { pr_err("Could not map UEFI random seed!\n"); -- cgit v1.2.3 From 286d3250c9d6437340203fb64938bea344729a0e Mon Sep 17 00:00:00 2001 From: Vladis Dronov Date: Sun, 8 Mar 2020 09:08:54 +0100 Subject: efi: Fix a race and a buffer overflow while reading efivars via sysfs There is a race and a buffer overflow corrupting a kernel memory while reading an EFI variable with a size more than 1024 bytes via the older sysfs method. This happens because accessing struct efi_variable in efivar_{attr,size,data}_read() and friends is not protected from a concurrent access leading to a kernel memory corruption and, at best, to a crash. The race scenario is the following: CPU0: CPU1: efivar_attr_read() var->DataSize = 1024; efivar_entry_get(... &var->DataSize) down_interruptible(&efivars_lock) efivar_attr_read() // same EFI var var->DataSize = 1024; efivar_entry_get(... &var->DataSize) down_interruptible(&efivars_lock) virt_efi_get_variable() // returns EFI_BUFFER_TOO_SMALL but // var->DataSize is set to a real // var size more than 1024 bytes up(&efivars_lock) virt_efi_get_variable() // called with var->DataSize set // to a real var size, returns // successfully and overwrites // a 1024-bytes kernel buffer up(&efivars_lock) This can be reproduced by concurrent reading of an EFI variable which size is more than 1024 bytes: ts# for cpu in $(seq 0 $(nproc --ignore=1)); do ( taskset -c $cpu \ cat /sys/firmware/efi/vars/KEKDefault*/size & ) ; done Fix this by using a local variable for a var's data buffer size so it does not get overwritten. Fixes: e14ab23dde12b80d ("efivars: efivar_entry API") Reported-by: Bob Sanders and the LTP testsuite Signed-off-by: Vladis Dronov Signed-off-by: Ard Biesheuvel Signed-off-by: Ingo Molnar Cc: Link: https://lore.kernel.org/r/20200305084041.24053-2-vdronov@redhat.com Link: https://lore.kernel.org/r/20200308080859.21568-24-ardb@kernel.org --- drivers/firmware/efi/efivars.c | 29 ++++++++++++++++++++--------- 1 file changed, 20 insertions(+), 9 deletions(-) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c index 7576450c8254..69f13bc4b931 100644 --- a/drivers/firmware/efi/efivars.c +++ b/drivers/firmware/efi/efivars.c @@ -83,13 +83,16 @@ static ssize_t efivar_attr_read(struct efivar_entry *entry, char *buf) { struct efi_variable *var = &entry->var; + unsigned long size = sizeof(var->Data); char *str = buf; + int ret; if (!entry || !buf) return -EINVAL; - var->DataSize = 1024; - if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data)) + ret = efivar_entry_get(entry, &var->Attributes, &size, var->Data); + var->DataSize = size; + if (ret) return -EIO; if (var->Attributes & EFI_VARIABLE_NON_VOLATILE) @@ -116,13 +119,16 @@ static ssize_t efivar_size_read(struct efivar_entry *entry, char *buf) { struct efi_variable *var = &entry->var; + unsigned long size = sizeof(var->Data); char *str = buf; + int ret; if (!entry || !buf) return -EINVAL; - var->DataSize = 1024; - if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data)) + ret = efivar_entry_get(entry, &var->Attributes, &size, var->Data); + var->DataSize = size; + if (ret) return -EIO; str += sprintf(str, "0x%lx\n", var->DataSize); @@ -133,12 +139,15 @@ static ssize_t efivar_data_read(struct efivar_entry *entry, char *buf) { struct efi_variable *var = &entry->var; + unsigned long size = sizeof(var->Data); + int ret; if (!entry || !buf) return -EINVAL; - var->DataSize = 1024; - if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data)) + ret = efivar_entry_get(entry, &var->Attributes, &size, var->Data); + var->DataSize = size; + if (ret) return -EIO; memcpy(buf, var->Data, var->DataSize); @@ -250,14 +259,16 @@ efivar_show_raw(struct efivar_entry *entry, char *buf) { struct efi_variable *var = &entry->var; struct compat_efi_variable *compat; + unsigned long datasize = sizeof(var->Data); size_t size; + int ret; if (!entry || !buf) return 0; - var->DataSize = 1024; - if (efivar_entry_get(entry, &entry->var.Attributes, - &entry->var.DataSize, entry->var.Data)) + ret = efivar_entry_get(entry, &var->Attributes, &datasize, var->Data); + var->DataSize = datasize; + if (ret) return -EIO; if (in_compat_syscall()) { -- cgit v1.2.3 From d6c066fda90d578aacdf19771a027ed484a79825 Mon Sep 17 00:00:00 2001 From: Vladis Dronov Date: Sun, 8 Mar 2020 09:08:55 +0100 Subject: efi: Add a sanity check to efivar_store_raw() Add a sanity check to efivar_store_raw() the same way efivar_{attr,size,data}_read() and efivar_show_raw() have it. Signed-off-by: Vladis Dronov Signed-off-by: Ard Biesheuvel Signed-off-by: Ingo Molnar Cc: Link: https://lore.kernel.org/r/20200305084041.24053-3-vdronov@redhat.com Link: https://lore.kernel.org/r/20200308080859.21568-25-ardb@kernel.org --- drivers/firmware/efi/efivars.c | 3 +++ 1 file changed, 3 insertions(+) (limited to 'drivers/firmware') diff --git a/drivers/firmware/efi/efivars.c b/drivers/firmware/efi/efivars.c index 69f13bc4b931..aff3dfb4d7ba 100644 --- a/drivers/firmware/efi/efivars.c +++ b/drivers/firmware/efi/efivars.c @@ -208,6 +208,9 @@ efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count) u8 *data; int err; + if (!entry || !buf) + return -EINVAL; + if (in_compat_syscall()) { struct compat_efi_variable *compat; -- cgit v1.2.3