From: Ben Hutchings ben@decadent.org.uk

commit 4d1aa9112c8e6995ef2c8a76972c9671332ccfea upstream.

This reverts commit cb9c1cfc86926d0e86d19c8e34f6c23458cd3478 for USB_LED_TRIG. This config symbol has bool type and enables extra code in usb_common itself, not a separate driver. Enabling it should not force usb_common to be built-in!

Fixes: cb9c1cfc8692 ("usb: Kconfig: using select for USB_COMMON dependency") Cc: stable stable@vger.kernel.org Signed-off-by: Ben Hutchings ben@decadent.org.uk Signed-off-by: Salvatore Bonaccorso carnil@debian.org Link: https://lore.kernel.org/r/20210921143442.340087-1-carnil@debian.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/Kconfig | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-)

--- a/drivers/usb/Kconfig +++ b/drivers/usb/Kconfig @@ -160,8 +160,7 @@ source "drivers/usb/gadget/Kconfig"

config USB_LED_TRIG bool "USB LED Triggers" - depends on LEDS_CLASS && LEDS_TRIGGERS - select USB_COMMON + depends on LEDS_CLASS && USB_COMMON && LEDS_TRIGGERS help This option adds LED triggers for USB host and/or gadget activity.

From: Johan Hovold johan@kernel.org

commit 58fc1daa4d2e9789b9ffc880907c961ea7c062cc upstream.

A recent change that started reporting break events forgot to push the event to the line discipline, which meant that a detected break would not be reported until further characters had been receive (the port could even have been closed and reopened in between).

Fixes: 08dff274edda ("cdc-acm: fix BREAK rx code path adding necessary calls") Cc: stable@vger.kernel.org Acked-by: Oliver Neukum oneukum@suse.com Signed-off-by: Johan Hovold johan@kernel.org Link: https://lore.kernel.org/r/20210929090937.7410-3-johan@kernel.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/usb/class/cdc-acm.c | 3 +++ 1 file changed, 3 insertions(+)

--- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -349,6 +349,9 @@ static void acm_ctrl_irq(struct urb *urb acm->iocount.overrun++; spin_unlock(&acm->read_lock);

+ if (newctrl & ACM_CTRL_BRK) + tty_flip_buffer_push(&acm->port); + if (difference) wake_up_all(&acm->wioctl);

From: Trond Myklebust trond.myklebust@hammerspace.com

commit f2e717d655040d632c9015f19aa4275f8b16e7f2 upstream.

RFC3530 notes that the 'dircount' field may be zero, in which case the recommendation is to ignore it, and only enforce the 'maxcount' field. In RFC5661, this recommendation to ignore a zero valued field becomes a requirement.

Fixes: aee377644146 ("nfsd4: fix rd_dircount enforcement") Cc: stable@vger.kernel.org Signed-off-by: Trond Myklebust trond.myklebust@hammerspace.com Signed-off-by: Chuck Lever chuck.lever@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/nfsd/nfs4xdr.c | 19 +++++++++++-------- 1 file changed, 11 insertions(+), 8 deletions(-)

--- a/fs/nfsd/nfs4xdr.c +++ b/fs/nfsd/nfs4xdr.c @@ -3028,15 +3028,18 @@ nfsd4_encode_dirent(void *ccdv, const ch goto fail; cd->rd_maxcount -= entry_bytes; /* - * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so - * let's always let through the first entry, at least: + * RFC 3530 14.2.24 describes rd_dircount as only a "hint", and + * notes that it could be zero. If it is zero, then the server + * should enforce only the rd_maxcount value. */ - if (!cd->rd_dircount) - goto fail; - name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8; - if (name_and_cookie > cd->rd_dircount && cd->cookie_offset) - goto fail; - cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie); + if (cd->rd_dircount) { + name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8; + if (name_and_cookie > cd->rd_dircount && cd->cookie_offset) + goto fail; + cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie); + if (!cd->rd_dircount) + cd->rd_maxcount = 0; + }

cd->cookie_offset = cookie_offset; skip_entry:

From: Max Filippov jcmvbkbc@gmail.com

[ Upstream commit 6489f8d0e1d93a3603d8dad8125797559e4cf2a2 ]

During boot time kernel configured with OF=y but USE_OF=n displays the following warnings and hangs shortly after starting userspace:

------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at kernel/irq/irqdomain.c:695 irq_create_mapping_affinity+0x29/0xc0 irq_create_mapping_affinity(, 6) called with NULL domain CPU: 0 PID: 0 Comm: swapper Not tainted 5.15.0-rc3-00001-gd67ed2510d28 #30 Call Trace: __warn+0x69/0xc4 warn_slowpath_fmt+0x6c/0x94 irq_create_mapping_affinity+0x29/0xc0 local_timer_setup+0x40/0x88 time_init+0xb1/0xe8 start_kernel+0x31d/0x3f4 _startup+0x13b/0x13b ---[ end trace 1e6630e1c5eda35b ]--- ------------[ cut here ]------------ WARNING: CPU: 0 PID: 0 at arch/xtensa/kernel/time.c:141 local_timer_setup+0x58/0x88 error: can't map timer irq CPU: 0 PID: 0 Comm: swapper Tainted: G W 5.15.0-rc3-00001-gd67ed2510d28 #30 Call Trace: __warn+0x69/0xc4 warn_slowpath_fmt+0x6c/0x94 local_timer_setup+0x58/0x88 time_init+0xb1/0xe8 start_kernel+0x31d/0x3f4 _startup+0x13b/0x13b ---[ end trace 1e6630e1c5eda35c ]--- Failed to request irq 0 (timer)

Fix that by calling irqchip_init only when CONFIG_USE_OF is selected and calling legacy interrupt controller init otherwise.

Fixes: da844a81779e ("xtensa: add device trees support") Signed-off-by: Max Filippov jcmvbkbc@gmail.com Signed-off-by: Sasha Levin sashal@kernel.org --- arch/xtensa/kernel/irq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/xtensa/kernel/irq.c b/arch/xtensa/kernel/irq.c index 441694464b1e..fbbc24b914e3 100644 --- a/arch/xtensa/kernel/irq.c +++ b/arch/xtensa/kernel/irq.c @@ -144,7 +144,7 @@ unsigned xtensa_get_ext_irq_no(unsigned irq)

void __init init_IRQ(void) { -#ifdef CONFIG_OF +#ifdef CONFIG_USE_OF irqchip_init(); #else #ifdef CONFIG_HAVE_SMP

From: Pavel Skripkin paskripkin@gmail.com

[ Upstream commit ca6e11c337daf7925ff8a2aac8e84490a8691905 ]

Syzbot reported memory leak in MDIO bus interface, the problem was in wrong state logic.

MDIOBUS_ALLOCATED indicates 2 states: 1. Bus is only allocated 2. Bus allocated and __mdiobus_register() fails, but device_register() was called

In case of device_register() has been called we should call put_device() to correctly free the memory allocated for this device, but mdiobus_free() calls just kfree(dev) in case of MDIOBUS_ALLOCATED state

To avoid this behaviour we need to set bus->state to MDIOBUS_UNREGISTERED _before_ calling device_register(), because put_device() should be called even in case of device_register() failure.

Link: https://lore.kernel.org/netdev/YVMRWNDZDUOvQjHL@shell.armlinux.org.uk/ Fixes: 46abc02175b3 ("phylib: give mdio buses a device tree presence") Reported-and-tested-by: syzbot+398e7dc692ddbbb4cfec@syzkaller.appspotmail.com Reviewed-by: Dan Carpenter dan.carpenter@oracle.com Signed-off-by: Pavel Skripkin paskripkin@gmail.com Link: https://lore.kernel.org/r/eceae1429fbf8fa5c73dd2a0d39d525aa905074d.163302406... Signed-off-by: Jakub Kicinski kuba@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/net/phy/mdio_bus.c | 7 +++++++ 1 file changed, 7 insertions(+)

diff --git a/drivers/net/phy/mdio_bus.c b/drivers/net/phy/mdio_bus.c index 8cc7563ab103..92fb664b56fb 100644 --- a/drivers/net/phy/mdio_bus.c +++ b/drivers/net/phy/mdio_bus.c @@ -316,6 +316,13 @@ int __mdiobus_register(struct mii_bus *bus, struct module *owner) bus->dev.groups = NULL; dev_set_name(&bus->dev, "%s", bus->id);

+ /* We need to set state to MDIOBUS_UNREGISTERED to correctly release + * the device in mdiobus_free() + * + * State will be updated later in this function in case of success + */ + bus->state = MDIOBUS_UNREGISTERED; + err = device_register(&bus->dev); if (err) { pr_err("mii_bus %s failed to register\n", bus->id);

From: Pali Rohár pali@kernel.org

[ Upstream commit eed183abc0d3b8adb64fd1363b7cea7986cd58d6 ]

Property phy-connection-type contains invalid value "sgmii-2500" per scheme defined in file ethernet-controller.yaml.

Correct phy-connection-type value should be "2500base-x".

Signed-off-by: Pali Rohár pali@kernel.org Fixes: 84e0f1c13806 ("powerpc/mpc85xx: Add MDIO bus muxing support to the board device tree(s)") Acked-by: Scott Wood oss@buserror.net Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- arch/powerpc/boot/dts/fsl/t1023rdb.dts | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/boot/dts/fsl/t1023rdb.dts b/arch/powerpc/boot/dts/fsl/t1023rdb.dts index 29757623e5ba..f5f8f969dd58 100644 --- a/arch/powerpc/boot/dts/fsl/t1023rdb.dts +++ b/arch/powerpc/boot/dts/fsl/t1023rdb.dts @@ -125,7 +125,7 @@

fm1mac3: ethernet@e4000 { phy-handle = <&sgmii_aqr_phy3>; - phy-connection-type = "sgmii-2500"; + phy-connection-type = "2500base-x"; sleep = <&rcpm 0x20000000>; };

From: Oleksij Rempel o.rempel@pengutronix.de

[ Upstream commit 783f3db030563f7bcdfe2d26428af98ea1699a8e ]

Any pending interrupt can prevent entering standby based power off state. To avoid it, disable the GIC CPU interface.

Fixes: 8148d2136002 ("ARM: imx6: register pm_power_off handler if "fsl,pmic-stby-poweroff" is set") Signed-off-by: Oleksij Rempel o.rempel@pengutronix.de Signed-off-by: Shawn Guo shawnguo@kernel.org Signed-off-by: Sasha Levin sashal@kernel.org --- arch/arm/mach-imx/pm-imx6.c | 2 ++ 1 file changed, 2 insertions(+)

diff --git a/arch/arm/mach-imx/pm-imx6.c b/arch/arm/mach-imx/pm-imx6.c index 6da26692f2fd..950c9f2ffe00 100644 --- a/arch/arm/mach-imx/pm-imx6.c +++ b/arch/arm/mach-imx/pm-imx6.c @@ -15,6 +15,7 @@ #include <linux/io.h> #include <linux/irq.h> #include <linux/genalloc.h> +#include <linux/irqchip/arm-gic.h> #include <linux/mfd/syscon.h> #include <linux/mfd/syscon/imx6q-iomuxc-gpr.h> #include <linux/of.h> @@ -606,6 +607,7 @@ static void __init imx6_pm_common_init(const struct imx6_pm_socdata

static void imx6_pm_stby_poweroff(void) { + gic_cpu_if_down(0); imx6_set_lpm(STOP_POWER_OFF); imx6q_suspend_finish(0);

From: Eric Dumazet edumazet@google.com

[ Upstream commit 7707a4d01a648e4c655101a469c956cb11273655 ]

While existing code is correct, KCSAN is reporting a data-race in netlink_insert / netlink_sendmsg [1]

It is correct to read nlk->bound without a lock, as netlink_autobind() will acquire all needed locks.

[1] BUG: KCSAN: data-race in netlink_insert / netlink_sendmsg

write to 0xffff8881031c8b30 of 1 bytes by task 18752 on cpu 0: netlink_insert+0x5cc/0x7f0 net/netlink/af_netlink.c:597 netlink_autobind+0xa9/0x150 net/netlink/af_netlink.c:842 netlink_sendmsg+0x479/0x7c0 net/netlink/af_netlink.c:1892 sock_sendmsg_nosec net/socket.c:703 [inline] sock_sendmsg net/socket.c:723 [inline] ____sys_sendmsg+0x360/0x4d0 net/socket.c:2392 ___sys_sendmsg net/socket.c:2446 [inline] __sys_sendmsg+0x1ed/0x270 net/socket.c:2475 __do_sys_sendmsg net/socket.c:2484 [inline] __se_sys_sendmsg net/socket.c:2482 [inline] __x64_sys_sendmsg+0x42/0x50 net/socket.c:2482 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881031c8b30 of 1 bytes by task 18751 on cpu 1: netlink_sendmsg+0x270/0x7c0 net/netlink/af_netlink.c:1891 sock_sendmsg_nosec net/socket.c:703 [inline] sock_sendmsg net/socket.c:723 [inline] __sys_sendto+0x2a8/0x370 net/socket.c:2019 __do_sys_sendto net/socket.c:2031 [inline] __se_sys_sendto net/socket.c:2027 [inline] __x64_sys_sendto+0x74/0x90 net/socket.c:2027 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0x90 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on: CPU: 1 PID: 18751 Comm: syz-executor.0 Not tainted 5.14.0-rc1-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: da314c9923fe ("netlink: Replace rhash_portid with bound") Signed-off-by: Eric Dumazet edumazet@google.com Reported-by: syzbot syzkaller@googlegroups.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/netlink/af_netlink.c | 14 ++++++++++---- 1 file changed, 10 insertions(+), 4 deletions(-)

diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 453b0efdc0d7..1b70de5898c4 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -574,7 +574,10 @@ static int netlink_insert(struct sock *sk, u32 portid)

/* We need to ensure that the socket is hashed and visible. */ smp_wmb(); - nlk_sk(sk)->bound = portid; + /* Paired with lockless reads from netlink_bind(), + * netlink_connect() and netlink_sendmsg(). + */ + WRITE_ONCE(nlk_sk(sk)->bound, portid);

err: release_sock(sk); @@ -993,7 +996,8 @@ static int netlink_bind(struct socket *sock, struct sockaddr *addr, else if (nlk->ngroups < 8*sizeof(groups)) groups &= (1UL << nlk->ngroups) - 1;

- bound = nlk->bound; + /* Paired with WRITE_ONCE() in netlink_insert() */ + bound = READ_ONCE(nlk->bound); if (bound) { /* Ensure nlk->portid is up-to-date. */ smp_rmb(); @@ -1073,8 +1077,9 @@ static int netlink_connect(struct socket *sock, struct sockaddr *addr,

/* No need for barriers here as we return to user-space without * using any of the bound attributes. + * Paired with WRITE_ONCE() in netlink_insert(). */ - if (!nlk->bound) + if (!READ_ONCE(nlk->bound)) err = netlink_autobind(sock);

if (err == 0) { @@ -1821,7 +1826,8 @@ static int netlink_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) dst_group = nlk->dst_group; }

- if (!nlk->bound) { + /* Paired with WRITE_ONCE() in netlink_insert() */ + if (!READ_ONCE(nlk->bound)) { err = netlink_autobind(sock); if (err) goto out;

From: Eric Dumazet edumazet@google.com

[ Upstream commit d34367991933d28bd7331f67a759be9a8c474014 ]

rtnl_fill_statsinfo() is filling skb with one mandatory if_stats_msg structure.

nlmsg_put(skb, pid, seq, type, sizeof(struct if_stats_msg), flags);

But if_nlmsg_stats_size() never considered the needed storage.

This bug did not show up because alloc_skb(X) allocates skb with extra tailroom, because of added alignments. This could very well be changed in the future to have deterministic behavior.

Fixes: 10c9ead9f3c6 ("rtnetlink: add new RTM_GETSTATS message to dump link stats") Signed-off-by: Eric Dumazet edumazet@google.com Cc: Roopa Prabhu roopa@nvidia.com Acked-by: Roopa Prabhu roopa@nvidia.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- net/core/rtnetlink.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index 911752e8a3e6..012143f313a8 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -3900,7 +3900,7 @@ nla_put_failure: static size_t if_nlmsg_stats_size(const struct net_device *dev, u32 filter_mask) { - size_t size = 0; + size_t size = NLMSG_ALIGN(sizeof(struct if_stats_msg));

if (stats_attr_valid(filter_mask, IFLA_STATS_LINK_64, 0)) size += nla_total_size_64bit(sizeof(struct rtnl_link_stats64));

From: Linus Torvalds torvalds@linux-foundation.org

commit 17839856fd588f4ab6b789f482ed3ffd7c403e1f upstream.

Doing a "get_user_pages()" on a copy-on-write page for reading can be ambiguous: the page can be COW'ed at any time afterwards, and the direction of a COW event isn't defined.

Yes, whoever writes to it will generally do the COW, but if the thread that did the get_user_pages() unmapped the page before the write (and that could happen due to memory pressure in addition to any outright action), the writer could also just take over the old page instead.

End result: the get_user_pages() call might result in a page pointer that is no longer associated with the original VM, and is associated with - and controlled by - another VM having taken it over instead.

So when doing a get_user_pages() on a COW mapping, the only really safe thing to do would be to break the COW when getting the page, even when only getting it for reading.

At the same time, some users simply don't even care.

For example, the perf code wants to look up the page not because it cares about the page, but because the code simply wants to look up the physical address of the access for informational purposes, and doesn't really care about races when a page might be unmapped and remapped elsewhere.

This adds logic to force a COW event by setting FOLL_WRITE on any copy-on-write mapping when FOLL_GET (or FOLL_PIN) is used to get a page pointer as a result.

The current semantics end up being:

- __get_user_pages_fast(): no change. If you don't ask for a write, you won't break COW. You'd better know what you're doing.

- get_user_pages_fast(): the fast-case "look it up in the page tables without anything getting mmap_sem" now refuses to follow a read-only page, since it might need COW breaking. Which happens in the slow path - the fast path doesn't know if the memory might be COW or not.

- get_user_pages() (including the slow-path fallback for gup_fast()): for a COW mapping, turn on FOLL_WRITE for FOLL_GET/FOLL_PIN, with very similar semantics to FOLL_FORCE.

If it turns out that we want finer granularity (ie "only break COW when it might actually matter" - things like the zero page are special and don't need to be broken) we might need to push these semantics deeper into the lookup fault path. So if people care enough, it's possible that we might end up adding a new internal FOLL_BREAK_COW flag to go with the internal FOLL_COW flag we already have for tracking "I had a COW".

Alternatively, if it turns out that different callers might want to explicitly control the forced COW break behavior, we might even want to make such a flag visible to the users of get_user_pages() instead of using the above default semantics.

But for now, this is mostly commentary on the issue (this commit message being a lot bigger than the patch, and that patch in turn is almost all comments), with that minimal "enable COW breaking early" logic using the existing FOLL_WRITE behavior.

[ It might be worth noting that we've always had this ambiguity, and it could arguably be seen as a user-space issue.

You only get private COW mappings that could break either way in situations where user space is doing cooperative things (ie fork() before an execve() etc), but it _is_ surprising and very subtle, and fork() is supposed to give you independent address spaces.

So let's treat this as a kernel issue and make the semantics of get_user_pages() easier to understand. Note that obviously a true shared mapping will still get a page that can change under us, so this does _not_ mean that get_user_pages() somehow returns any "stable" page ]

[surenb: backport notes Since gup_pgd_range does not exist, made appropriate changes on the the gup_huge_pgd, gup_huge_pd and gup_pud_range calls instead. Replaced (gup_flags | FOLL_WRITE) with write=1 in gup_huge_pgd, gup_huge_pd and gup_pud_range. Removed FOLL_PIN usage in should_force_cow_break since it's missing in the earlier kernels.]

Reported-by: Jann Horn jannh@google.com Tested-by: Christoph Hellwig hch@lst.de Acked-by: Oleg Nesterov oleg@redhat.com Acked-by: Kirill Shutemov kirill@shutemov.name Acked-by: Jan Kara jack@suse.cz Cc: Andrea Arcangeli aarcange@redhat.com Cc: Matthew Wilcox willy@infradead.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org [surenb: backport to 4.9 kernel] Signed-off-by: Suren Baghdasaryan surenb@google.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- mm/gup.c | 48 ++++++++++++++++++++++++++++++++++++++++-------- mm/huge_memory.c | 7 +++---- 2 files changed, 43 insertions(+), 12 deletions(-)

--- a/mm/gup.c +++ b/mm/gup.c @@ -61,13 +61,22 @@ static int follow_pfn_pte(struct vm_area }

/* - * FOLL_FORCE can write to even unwritable pte's, but only - * after we've gone through a COW cycle and they are dirty. + * FOLL_FORCE or a forced COW break can write even to unwritable pte's, + * but only after we've gone through a COW cycle and they are dirty. */ static inline bool can_follow_write_pte(pte_t pte, unsigned int flags) { - return pte_write(pte) || - ((flags & FOLL_FORCE) && (flags & FOLL_COW) && pte_dirty(pte)); + return pte_write(pte) || ((flags & FOLL_COW) && pte_dirty(pte)); +} + +/* + * A (separate) COW fault might break the page the other way and + * get_user_pages() would return the page from what is now the wrong + * VM. So we need to force a COW break at GUP time even for reads. + */ +static inline bool should_force_cow_break(struct vm_area_struct *vma, unsigned int flags) +{ + return is_cow_mapping(vma->vm_flags) && (flags & FOLL_GET); }

static struct page *follow_page_pte(struct vm_area_struct *vma, @@ -577,12 +586,18 @@ static long __get_user_pages(struct task if (!vma || check_vma_flags(vma, gup_flags)) return i ? : -EFAULT; if (is_vm_hugetlb_page(vma)) { + if (should_force_cow_break(vma, foll_flags)) + foll_flags |= FOLL_WRITE; i = follow_hugetlb_page(mm, vma, pages, vmas, &start, &nr_pages, i, - gup_flags); + foll_flags); continue; } } + + if (should_force_cow_break(vma, foll_flags)) + foll_flags |= FOLL_WRITE; + retry: /* * If we have a pending SIGKILL, don't keep faulting pages and @@ -1503,6 +1518,10 @@ static int gup_pud_range(pgd_t pgd, unsi /* * Like get_user_pages_fast() except it's IRQ-safe in that it won't fall back to * the regular GUP. It will only return non-negative values. + * + * Careful, careful! COW breaking can go either way, so a non-write + * access can get ambiguous page results. If you call this function without + * 'write' set, you'd better be sure that you're ok with that ambiguity. */ int __get_user_pages_fast(unsigned long start, int nr_pages, int write, struct page **pages) @@ -1532,6 +1551,12 @@ int __get_user_pages_fast(unsigned long * * We do not adopt an rcu_read_lock(.) here as we also want to * block IPIs that come from THPs splitting. + * + * NOTE! We allow read-only gup_fast() here, but you'd better be + * careful about possible COW pages. You'll get _a_ COW page, but + * not necessarily the one you intended to get depending on what + * COW event happens after this. COW may break the page copy in a + * random direction. */

local_irq_save(flags); @@ -1542,15 +1567,22 @@ int __get_user_pages_fast(unsigned long next = pgd_addr_end(addr, end); if (pgd_none(pgd)) break; + /* + * The FAST_GUP case requires FOLL_WRITE even for pure reads, + * because get_user_pages() may need to cause an early COW in + * order to avoid confusing the normal COW routines. So only + * targets that are already writable are safe to do by just + * looking at the page tables. + */ if (unlikely(pgd_huge(pgd))) { - if (!gup_huge_pgd(pgd, pgdp, addr, next, write, + if (!gup_huge_pgd(pgd, pgdp, addr, next, 1, pages, &nr)) break; } else if (unlikely(is_hugepd(__hugepd(pgd_val(pgd))))) { if (!gup_huge_pd(__hugepd(pgd_val(pgd)), addr, - PGDIR_SHIFT, next, write, pages, &nr)) + PGDIR_SHIFT, next, 1, pages, &nr)) break; - } else if (!gup_pud_range(pgd, addr, next, write, pages, &nr)) + } else if (!gup_pud_range(pgd, addr, next, 1, pages, &nr)) break; } while (pgdp++, addr = next, addr != end); local_irq_restore(flags); --- a/mm/huge_memory.c +++ b/mm/huge_memory.c @@ -1135,13 +1135,12 @@ out_unlock: }

/* - * FOLL_FORCE can write to even unwritable pmd's, but only - * after we've gone through a COW cycle and they are dirty. + * FOLL_FORCE or a forced COW break can write even to unwritable pmd's, + * but only after we've gone through a COW cycle and they are dirty. */ static inline bool can_follow_write_pmd(pmd_t pmd, unsigned int flags) { - return pmd_write(pmd) || - ((flags & FOLL_FORCE) && (flags & FOLL_COW) && pmd_dirty(pmd)); + return pmd_write(pmd) || ((flags & FOLL_COW) && pmd_dirty(pmd)); }

struct page *follow_trans_huge_pmd(struct vm_area_struct *vma,

From: Jeremy Sowden jeremy@azazel.net

[ Upstream commit 310e2d43c3ad429c1fba4b175806cf1f55ed73a6 ]

ip6tables only sets the `IP6T_F_PROTO` flag on a rule if a protocol is specified (`-p tcp`, for example). However, if the flag is not set, `ip6_packet_match` doesn't call `ipv6_find_hdr` for the skb, in which case the fragment offset is left uninitialized and a garbage value is passed to each matcher.

Signed-off-by: Jeremy Sowden jeremy@azazel.net Reviewed-by: Florian Westphal fw@strlen.de Signed-off-by: Pablo Neira Ayuso pablo@netfilter.org Signed-off-by: Sasha Levin sashal@kernel.org --- net/ipv6/netfilter/ip6_tables.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/net/ipv6/netfilter/ip6_tables.c b/net/ipv6/netfilter/ip6_tables.c index 579fda1bc45d..ce54e66b47a0 100644 --- a/net/ipv6/netfilter/ip6_tables.c +++ b/net/ipv6/netfilter/ip6_tables.c @@ -290,6 +290,7 @@ ip6t_do_table(struct sk_buff *skb, * things we don't know, ie. tcp syn flag or ports). If the * rule is also a fragment-specific rule, non-fragments won't * match it. */ + acpar.fragoff = 0; acpar.hotdrop = false; acpar.net = state->net; acpar.in = state->in;

From: Jiapeng Chong jiapeng.chong@linux.alibaba.com

[ Upstream commit dd689ed5aa905daf4ba4c99319a52aad6ea0a796 ]

Fix the following coccicheck warning:

./drivers/scsi/ses.c:137:10-16: WARNING: Unsigned expression compared with zero: result > 0.

Link: https://lore.kernel.org/r/1632477113-90378-1-git-send-email-jiapeng.chong@li... Reported-by: Abaci Robot abaci@linux.alibaba.com Signed-off-by: Jiapeng Chong jiapeng.chong@linux.alibaba.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/scsi/ses.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/scsi/ses.c b/drivers/scsi/ses.c index 69046d342bc5..39396548f9b5 100644 --- a/drivers/scsi/ses.c +++ b/drivers/scsi/ses.c @@ -120,7 +120,7 @@ static int ses_recv_diag(struct scsi_device *sdev, int page_code, static int ses_send_diag(struct scsi_device *sdev, int page_code, void *buf, int bufflen) { - u32 result; + int result;

unsigned char cmd[] = { SEND_DIAGNOSTIC,

From: Anand K Mistry amistry@google.com

[ Upstream commit 02d029a41dc986e2d5a77ecca45803857b346829 ]

perf_init_event tries multiple init callbacks and does not reset the event state between tries. When x86_pmu_event_init runs, it unconditionally sets the destroy callback to hw_perf_event_destroy. On the next init attempt after x86_pmu_event_init, in perf_try_init_event, if the pmu's capabilities includes PERF_PMU_CAP_NO_EXCLUDE, the destroy callback will be run. However, if the next init didn't set the destroy callback, hw_perf_event_destroy will be run (since the callback wasn't reset).

Looking at other pmu init functions, the common pattern is to only set the destroy callback on a successful init. Resetting the callback on failure tries to replicate that pattern.

This was discovered after commit f11dd0d80555 ("perf/x86/amd/ibs: Extend PERF_PMU_CAP_NO_EXCLUDE to IBS Op") when the second (and only second) run of the perf tool after a reboot results in 0 samples being generated. The extra run of hw_perf_event_destroy results in active_events having an extra decrement on each perf run. The second run has active_events == 0 and every subsequent run has active_events < 0. When active_events == 0, the NMI handler will early-out and not record any samples.

Signed-off-by: Anand K Mistry amistry@google.com Signed-off-by: Peter Zijlstra (Intel) peterz@infradead.org Link: https://lkml.kernel.org/r/20210929170405.1.I078b98ee7727f9ae9d6df8262bad7e32... Signed-off-by: Sasha Levin sashal@kernel.org --- arch/x86/events/core.c | 1 + 1 file changed, 1 insertion(+)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index c26cca506f64..c20df6a3540c 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c @@ -2075,6 +2075,7 @@ static int x86_pmu_event_init(struct perf_event *event) if (err) { if (event->destroy) event->destroy(event); + event->destroy = NULL; }

if (ACCESS_ONCE(x86_pmu.attr_rdpmc))