From: Allen Pais apais@linux.microsoft.com

[ Upstream commit 914ab19e471d8fb535ed50dff108b0a615f3c2d8 ]

Implement a .shutdown hook that will be called during a kexec operation so that the TEE shared memory, session, and context that were set up during .probe can be properly freed/closed.

Additionally, don't use dma-buf backed shared memory for the fw_shm_pool. dma-buf backed shared memory cannot be reliably freed and unregistered during a kexec operation even when tee_shm_free() is called on the shm from a .shutdown hook. The problem occurs because dma_buf_put() calls fput() which then uses task_work_add(), with the TWA_RESUME parameter, to queue tee_shm_release() to be called before the current task returns to user mode. However, the current task never returns to user mode before the kexec completes so the memory is never freed nor unregistered.

Use tee_shm_alloc_kernel_buf() to avoid dma-buf backed shared memory allocation so that tee_shm_free() can directly call tee_shm_release(). This will ensure that the shm can be freed and unregistered during a kexec operation.

Fixes: 246880958ac9 ("firmware: broadcom: add OP-TEE based BNXT f/w manager") Cc: stable@vger.kernel.org Signed-off-by: Allen Pais apais@linux.microsoft.com Co-developed-by: Tyler Hicks tyhicks@linux.microsoft.com Signed-off-by: Tyler Hicks tyhicks@linux.microsoft.com Reviewed-by: Sumit Garg sumit.garg@linaro.org Acked-by: Florian Fainelli f.fainelli@gmail.com Signed-off-by: Jens Wiklander jens.wiklander@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/firmware/broadcom/tee_bnxt_fw.c | 14 +++++++++++--- 1 file changed, 11 insertions(+), 3 deletions(-)

--- a/drivers/firmware/broadcom/tee_bnxt_fw.c +++ b/drivers/firmware/broadcom/tee_bnxt_fw.c @@ -212,10 +212,9 @@ static int tee_bnxt_fw_probe(struct devi

pvt_data.dev = dev;

- fw_shm_pool = tee_shm_alloc(pvt_data.ctx, MAX_SHM_MEM_SZ, - TEE_SHM_MAPPED | TEE_SHM_DMA_BUF); + fw_shm_pool = tee_shm_alloc_kernel_buf(pvt_data.ctx, MAX_SHM_MEM_SZ); if (IS_ERR(fw_shm_pool)) { - dev_err(pvt_data.dev, "tee_shm_alloc failed\n"); + dev_err(pvt_data.dev, "tee_shm_alloc_kernel_buf failed\n"); err = PTR_ERR(fw_shm_pool); goto out_sess; } @@ -242,6 +241,14 @@ static int tee_bnxt_fw_remove(struct dev return 0; }

+static void tee_bnxt_fw_shutdown(struct device *dev) +{ + tee_shm_free(pvt_data.fw_shm_pool); + tee_client_close_session(pvt_data.ctx, pvt_data.session_id); + tee_client_close_context(pvt_data.ctx); + pvt_data.ctx = NULL; +} + static const struct tee_client_device_id tee_bnxt_fw_id_table[] = { {UUID_INIT(0x6272636D, 0x2019, 0x0716, 0x42, 0x43, 0x4D, 0x5F, 0x53, 0x43, 0x48, 0x49)}, @@ -257,6 +264,7 @@ static struct tee_client_driver tee_bnxt .bus = &tee_bus_type, .probe = tee_bnxt_fw_probe, .remove = tee_bnxt_fw_remove, + .shutdown = tee_bnxt_fw_shutdown, }, };

From: Daniel Borkmann daniel@iogearbox.net

commit 51e1bb9eeaf7868db56e58f47848e364ab4c4129 upstream.

Back then, commit 96ae52279594 ("bpf: Add bpf_probe_write_user BPF helper to be called in tracers") added the bpf_probe_write_user() helper in order to allow to override user space memory. Its original goal was to have a facility to "debug, divert, and manipulate execution of semi-cooperative processes" under CAP_SYS_ADMIN. Write to kernel was explicitly disallowed since it would otherwise tamper with its integrity.

One use case was shown in cf9b1199de27 ("samples/bpf: Add test/example of using bpf_probe_write_user bpf helper") where the program DNATs traffic at the time of connect(2) syscall, meaning, it rewrites the arguments to a syscall while they're still in userspace, and before the syscall has a chance to copy the argument into kernel space. These days we have better mechanisms in BPF for achieving the same (e.g. for load-balancers), but without having to write to userspace memory.

Of course the bpf_probe_write_user() helper can also be used to abuse many other things for both good or bad purpose. Outside of BPF, there is a similar mechanism for ptrace(2) such as PTRACE_PEEK{TEXT,DATA} and PTRACE_POKE{TEXT,DATA}, but would likely require some more effort. Commit 96ae52279594 explicitly dedicated the helper for experimentation purpose only. Thus, move the helper's availability behind a newly added LOCKDOWN_BPF_WRITE_USER lockdown knob so that the helper is disabled under the "integrity" mode. More fine-grained control can be implemented also from LSM side with this change.

Fixes: 96ae52279594 ("bpf: Add bpf_probe_write_user BPF helper to be called in tracers") Signed-off-by: Daniel Borkmann daniel@iogearbox.net Acked-by: Andrii Nakryiko andrii@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- include/linux/security.h | 1 + kernel/trace/bpf_trace.c | 5 +++-- security/security.c | 1 + 3 files changed, 5 insertions(+), 2 deletions(-)

--- a/include/linux/security.h +++ b/include/linux/security.h @@ -120,6 +120,7 @@ enum lockdown_reason { LOCKDOWN_MMIOTRACE, LOCKDOWN_DEBUGFS, LOCKDOWN_XMON_WR, + LOCKDOWN_BPF_WRITE_USER, LOCKDOWN_INTEGRITY_MAX, LOCKDOWN_KCORE, LOCKDOWN_KPROBES, --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -990,12 +990,13 @@ bpf_tracing_func_proto(enum bpf_func_id return &bpf_get_numa_node_id_proto; case BPF_FUNC_perf_event_read: return &bpf_perf_event_read_proto; - case BPF_FUNC_probe_write_user: - return bpf_get_probe_write_proto(); case BPF_FUNC_current_task_under_cgroup: return &bpf_current_task_under_cgroup_proto; case BPF_FUNC_get_prandom_u32: return &bpf_get_prandom_u32_proto; + case BPF_FUNC_probe_write_user: + return security_locked_down(LOCKDOWN_BPF_WRITE_USER) < 0 ? + NULL : bpf_get_probe_write_proto(); case BPF_FUNC_probe_read_user: return &bpf_probe_read_user_proto; case BPF_FUNC_probe_read_kernel: --- a/security/security.c +++ b/security/security.c @@ -58,6 +58,7 @@ const char *const lockdown_reasons[LOCKD [LOCKDOWN_MMIOTRACE] = "unsafe mmio", [LOCKDOWN_DEBUGFS] = "debugfs access", [LOCKDOWN_XMON_WR] = "xmon write access", + [LOCKDOWN_BPF_WRITE_USER] = "use of bpf to write user RAM", [LOCKDOWN_INTEGRITY_MAX] = "integrity", [LOCKDOWN_KCORE] = "/proc/kcore access", [LOCKDOWN_KPROBES] = "use of kprobes",

From: Jeremy Szu jeremy.szu@canonical.com

commit d07149aba2ef423eae94a9cc2a6365d0cdf6fd51 upstream.

The HP ProBook 650 G8 Notebook PC is using ALC236 codec which is using 0x02 to control mute LED and 0x01 to control micmute LED. Therefore, add a quirk to make it works.

Signed-off-by: Jeremy Szu jeremy.szu@canonical.com Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20210810100846.65844-1-jeremy.szu@canonical.com Signed-off-by: Takashi Iwai tiwai@suse.de Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- sound/pci/hda/patch_realtek.c | 1 + 1 file changed, 1 insertion(+)

--- a/sound/pci/hda/patch_realtek.c +++ b/sound/pci/hda/patch_realtek.c @@ -8371,6 +8371,7 @@ static const struct snd_pci_quirk alc269 SND_PCI_QUIRK(0x103c, 0x87f4, "HP", ALC287_FIXUP_HP_GPIO_LED), SND_PCI_QUIRK(0x103c, 0x87f5, "HP", ALC287_FIXUP_HP_GPIO_LED), SND_PCI_QUIRK(0x103c, 0x87f7, "HP Spectre x360 14", ALC245_FIXUP_HP_X360_AMP), + SND_PCI_QUIRK(0x103c, 0x8805, "HP ProBook 650 G8 Notebook PC", ALC236_FIXUP_HP_GPIO_LED), SND_PCI_QUIRK(0x103c, 0x880d, "HP EliteBook 830 G8 Notebook PC", ALC285_FIXUP_HP_GPIO_LED), SND_PCI_QUIRK(0x103c, 0x8846, "HP EliteBook 850 G8 Notebook PC", ALC285_FIXUP_HP_GPIO_LED), SND_PCI_QUIRK(0x103c, 0x8847, "HP EliteBook x360 830 G8 Notebook PC", ALC285_FIXUP_HP_GPIO_LED),

From: Pali Rohár pali@kernel.org

commit 3125f26c514826077f2a4490b75e9b1c7a644c42 upstream.

When registering new ppp interface via PPPIOCNEWUNIT ioctl then kernel has to choose interface name as this ioctl API does not support specifying it.

Kernel in this case register new interface with name "ppp<id>" where <id> is the ppp unit id, which can be obtained via PPPIOCGUNIT ioctl. This applies also in the case when registering new ppp interface via rtnl without supplying IFLA_IFNAME.

PPPIOCNEWUNIT ioctl allows to specify own ppp unit id which will kernel assign to ppp interface, in case this ppp id is not already used by other ppp interface.

In case user does not specify ppp unit id then kernel choose the first free ppp unit id. This applies also for case when creating ppp interface via rtnl method as it does not provide a way for specifying own ppp unit id.

If some network interface (does not have to be ppp) has name "ppp<id>" with this first free ppp id then PPPIOCNEWUNIT ioctl or rtnl call fails.

And registering new ppp interface is not possible anymore, until interface which holds conflicting name is renamed. Or when using rtnl method with custom interface name in IFLA_IFNAME.

As list of allocated / used ppp unit ids is not possible to retrieve from kernel to userspace, userspace has no idea what happens nor which interface is doing this conflict.

So change the algorithm how ppp unit id is generated. And choose the first number which is not neither used as ppp unit id nor in some network interface with pattern "ppp<id>".

This issue can be simply reproduced by following pppd call when there is no ppp interface registered and also no interface with name pattern "ppp<id>":

pppd ifname ppp1 +ipv6 noip noauth nolock local nodetach pty "pppd +ipv6 noip noauth nolock local nodetach notty"

Or by creating the one ppp interface (which gets assigned ppp unit id 0), renaming it to "ppp1" and then trying to create a new ppp interface (which will always fails as next free ppp unit id is 1, but network interface with name "ppp1" exists).

This patch fixes above described issue by generating new and new ppp unit id until some non-conflicting id with network interfaces is generated.

Signed-off-by: Pali Rohár pali@kernel.org Cc: stable@vger.kernel.org Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/ppp/ppp_generic.c | 19 +++++++++++++++---- 1 file changed, 15 insertions(+), 4 deletions(-)

--- a/drivers/net/ppp/ppp_generic.c +++ b/drivers/net/ppp/ppp_generic.c @@ -284,7 +284,7 @@ static struct channel *ppp_find_channel( static int ppp_connect_channel(struct channel *pch, int unit); static int ppp_disconnect_channel(struct channel *pch); static void ppp_destroy_channel(struct channel *pch); -static int unit_get(struct idr *p, void *ptr); +static int unit_get(struct idr *p, void *ptr, int min); static int unit_set(struct idr *p, void *ptr, int n); static void unit_put(struct idr *p, int n); static void *unit_find(struct idr *p, int n); @@ -1155,9 +1155,20 @@ static int ppp_unit_register(struct ppp mutex_lock(&pn->all_ppp_mutex);

if (unit < 0) { - ret = unit_get(&pn->units_idr, ppp); + ret = unit_get(&pn->units_idr, ppp, 0); if (ret < 0) goto err; + if (!ifname_is_set) { + while (1) { + snprintf(ppp->dev->name, IFNAMSIZ, "ppp%i", ret); + if (!__dev_get_by_name(ppp->ppp_net, ppp->dev->name)) + break; + unit_put(&pn->units_idr, ret); + ret = unit_get(&pn->units_idr, ppp, ret + 1); + if (ret < 0) + goto err; + } + } } else { /* Caller asked for a specific unit number. Fail with -EEXIST * if unavailable. For backward compatibility, return -EEXIST @@ -3552,9 +3563,9 @@ static int unit_set(struct idr *p, void }

/* get new free unit number and associate pointer with it */ -static int unit_get(struct idr *p, void *ptr) +static int unit_get(struct idr *p, void *ptr, int min) { - return idr_alloc(p, ptr, 0, 0, GFP_KERNEL); + return idr_alloc(p, ptr, min, 0, GFP_KERNEL); }

/* put unit number back to a pool */