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FAILED: patch "[PATCH] mm: zswap: properly synchronize freeing resources during CPU" failed to apply to 6.12-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 6.12-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-6.12.y git checkout FETCH_HEAD git cherry-pick -x 12dcb0ef540629a281533f9dedc1b6b8e14cfb65 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025012011-urgency-shredder-353e@gregkh' --subject-prefix 'PATCH 6.12.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 12dcb0ef540629a281533f9dedc1b6b8e14cfb65 Mon Sep 17 00:00:00 2001 From: Yosry Ahmed <yosryahmed(a)google.com> Date: Wed, 8 Jan 2025 22:24:41 +0000 Subject: [PATCH] mm: zswap: properly synchronize freeing resources during CPU hotunplug In zswap_compress() and zswap_decompress(), the per-CPU acomp_ctx of the current CPU at the beginning of the operation is retrieved and used throughout. However, since neither preemption nor migration are disabled, it is possible that the operation continues on a different CPU. If the original CPU is hotunplugged while the acomp_ctx is still in use, we run into a UAF bug as some of the resources attached to the acomp_ctx are freed during hotunplug in zswap_cpu_comp_dead() (i.e. acomp_ctx.buffer, acomp_ctx.req, or acomp_ctx.acomp). The problem was introduced in commit 1ec3b5fe6eec ("mm/zswap: move to use crypto_acomp API for hardware acceleration") when the switch to the crypto_acomp API was made. Prior to that, the per-CPU crypto_comp was retrieved using get_cpu_ptr() which disables preemption and makes sure the CPU cannot go away from under us. Preemption cannot be disabled with the crypto_acomp API as a sleepable context is needed. Use the acomp_ctx.mutex to synchronize CPU hotplug callbacks allocating and freeing resources with compression/decompression paths. Make sure that acomp_ctx.req is NULL when the resources are freed. In the compression/decompression paths, check if acomp_ctx.req is NULL after acquiring the mutex (meaning the CPU was offlined) and retry on the new CPU. The initialization of acomp_ctx.mutex is moved from the CPU hotplug callback to the pool initialization where it belongs (where the mutex is allocated). In addition to adding clarity, this makes sure that CPU hotplug cannot reinitialize a mutex that is already locked by compression/decompression. Previously a fix was attempted by holding cpus_read_lock() [1]. This would have caused a potential deadlock as it is possible for code already holding the lock to fall into reclaim and enter zswap (causing a deadlock). A fix was also attempted using SRCU for synchronization, but Johannes pointed out that synchronize_srcu() cannot be used in CPU hotplug notifiers [2]. Alternative fixes that were considered/attempted and could have worked: - Refcounting the per-CPU acomp_ctx. This involves complexity in handling the race between the refcount dropping to zero in zswap_[de]compress() and the refcount being re-initialized when the CPU is onlined. - Disabling migration before getting the per-CPU acomp_ctx [3], but that's discouraged and is a much bigger hammer than needed, and could result in subtle performance issues. [1]https://lkml.kernel.org/20241219212437.2714151-1-yosryahmed@google.com/ [2]https://lkml.kernel.org/20250107074724.1756696-2-yosryahmed@google.com/ [3]https://lkml.kernel.org/20250107222236.2715883-2-yosryahmed@google.com/ [yosryahmed(a)google.com: remove comment] Link: https://lkml.kernel.org/r/CAJD7tkaxS1wjn+swugt8QCvQ-rVF5RZnjxwPGX17k8x9zSMa… Link: https://lkml.kernel.org/r/20250108222441.3622031-1-yosryahmed@google.com Fixes: 1ec3b5fe6eec ("mm/zswap: move to use crypto_acomp API for hardware acceleration") Signed-off-by: Yosry Ahmed <yosryahmed(a)google.com> Reported-by: Johannes Weiner <hannes(a)cmpxchg.org> Closes: https://lore.kernel.org/lkml/20241113213007.GB1564047@cmpxchg.org/ Reported-by: Sam Sun <samsun1006219(a)gmail.com> Closes: https://lore.kernel.org/lkml/CAEkJfYMtSdM5HceNsXUDf5haghD5+o2e7Qv4OcuruL4tP… Cc: Barry Song <baohua(a)kernel.org> Cc: Chengming Zhou <chengming.zhou(a)linux.dev> Cc: Kanchana P Sridhar <kanchana.p.sridhar(a)intel.com> Cc: Nhat Pham <nphamcs(a)gmail.com> Cc: Vitaly Wool <vitalywool(a)gmail.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> diff --git a/mm/zswap.c b/mm/zswap.c index f6316b66fb23..30f5a27a6862 100644 --- a/mm/zswap.c +++ b/mm/zswap.c @@ -251,7 +251,7 @@ static struct zswap_pool *zswap_pool_create(char *type, char *compressor) struct zswap_pool *pool; char name[38]; /* 'zswap' + 32 char (max) num + \0 */ gfp_t gfp = __GFP_NORETRY | __GFP_NOWARN | __GFP_KSWAPD_RECLAIM; - int ret; + int ret, cpu; if (!zswap_has_pool) { /* if either are unset, pool initialization failed, and we @@ -285,6 +285,9 @@ static struct zswap_pool *zswap_pool_create(char *type, char *compressor) goto error; } + for_each_possible_cpu(cpu) + mutex_init(&per_cpu_ptr(pool->acomp_ctx, cpu)->mutex); + ret = cpuhp_state_add_instance(CPUHP_MM_ZSWP_POOL_PREPARE, &pool->node); if (ret) @@ -821,11 +824,12 @@ static int zswap_cpu_comp_prepare(unsigned int cpu, struct hlist_node *node) struct acomp_req *req; int ret; - mutex_init(&acomp_ctx->mutex); - + mutex_lock(&acomp_ctx->mutex); acomp_ctx->buffer = kmalloc_node(PAGE_SIZE * 2, GFP_KERNEL, cpu_to_node(cpu)); - if (!acomp_ctx->buffer) - return -ENOMEM; + if (!acomp_ctx->buffer) { + ret = -ENOMEM; + goto buffer_fail; + } acomp = crypto_alloc_acomp_node(pool->tfm_name, 0, 0, cpu_to_node(cpu)); if (IS_ERR(acomp)) { @@ -855,12 +859,15 @@ static int zswap_cpu_comp_prepare(unsigned int cpu, struct hlist_node *node) acomp_request_set_callback(req, CRYPTO_TFM_REQ_MAY_BACKLOG, crypto_req_done, &acomp_ctx->wait); + mutex_unlock(&acomp_ctx->mutex); return 0; req_fail: crypto_free_acomp(acomp_ctx->acomp); acomp_fail: kfree(acomp_ctx->buffer); +buffer_fail: + mutex_unlock(&acomp_ctx->mutex); return ret; } @@ -869,17 +876,45 @@ static int zswap_cpu_comp_dead(unsigned int cpu, struct hlist_node *node) struct zswap_pool *pool = hlist_entry(node, struct zswap_pool, node); struct crypto_acomp_ctx *acomp_ctx = per_cpu_ptr(pool->acomp_ctx, cpu); + mutex_lock(&acomp_ctx->mutex); if (!IS_ERR_OR_NULL(acomp_ctx)) { if (!IS_ERR_OR_NULL(acomp_ctx->req)) acomp_request_free(acomp_ctx->req); + acomp_ctx->req = NULL; if (!IS_ERR_OR_NULL(acomp_ctx->acomp)) crypto_free_acomp(acomp_ctx->acomp); kfree(acomp_ctx->buffer); } + mutex_unlock(&acomp_ctx->mutex); return 0; } +static struct crypto_acomp_ctx *acomp_ctx_get_cpu_lock(struct zswap_pool *pool) +{ + struct crypto_acomp_ctx *acomp_ctx; + + for (;;) { + acomp_ctx = raw_cpu_ptr(pool->acomp_ctx); + mutex_lock(&acomp_ctx->mutex); + if (likely(acomp_ctx->req)) + return acomp_ctx; + /* + * It is possible that we were migrated to a different CPU after + * getting the per-CPU ctx but before the mutex was acquired. If + * the old CPU got offlined, zswap_cpu_comp_dead() could have + * already freed ctx->req (among other things) and set it to + * NULL. Just try again on the new CPU that we ended up on. + */ + mutex_unlock(&acomp_ctx->mutex); + } +} + +static void acomp_ctx_put_unlock(struct crypto_acomp_ctx *acomp_ctx) +{ + mutex_unlock(&acomp_ctx->mutex); +} + static bool zswap_compress(struct page *page, struct zswap_entry *entry, struct zswap_pool *pool) { @@ -893,10 +928,7 @@ static bool zswap_compress(struct page *page, struct zswap_entry *entry, gfp_t gfp; u8 *dst; - acomp_ctx = raw_cpu_ptr(pool->acomp_ctx); - - mutex_lock(&acomp_ctx->mutex); - + acomp_ctx = acomp_ctx_get_cpu_lock(pool); dst = acomp_ctx->buffer; sg_init_table(&input, 1); sg_set_page(&input, page, PAGE_SIZE, 0); @@ -949,7 +981,7 @@ static bool zswap_compress(struct page *page, struct zswap_entry *entry, else if (alloc_ret) zswap_reject_alloc_fail++; - mutex_unlock(&acomp_ctx->mutex); + acomp_ctx_put_unlock(acomp_ctx); return comp_ret == 0 && alloc_ret == 0; } @@ -960,9 +992,7 @@ static void zswap_decompress(struct zswap_entry *entry, struct folio *folio) struct crypto_acomp_ctx *acomp_ctx; u8 *src; - acomp_ctx = raw_cpu_ptr(entry->pool->acomp_ctx); - mutex_lock(&acomp_ctx->mutex); - + acomp_ctx = acomp_ctx_get_cpu_lock(entry->pool); src = zpool_map_handle(zpool, entry->handle, ZPOOL_MM_RO); /* * If zpool_map_handle is atomic, we cannot reliably utilize its mapped buffer @@ -986,10 +1016,10 @@ static void zswap_decompress(struct zswap_entry *entry, struct folio *folio) acomp_request_set_params(acomp_ctx->req, &input, &output, entry->length, PAGE_SIZE); BUG_ON(crypto_wait_req(crypto_acomp_decompress(acomp_ctx->req), &acomp_ctx->wait)); BUG_ON(acomp_ctx->req->dlen != PAGE_SIZE); - mutex_unlock(&acomp_ctx->mutex); if (src != acomp_ctx->buffer) zpool_unmap_handle(zpool, entry->handle); + acomp_ctx_put_unlock(acomp_ctx); } /*********************************

10 months

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Re: Patch "fs: Block writes to mounted block devices" should probably be ported to 6.6 LTS.

by Jan Kara

Hello! On Tue 21-01-25 08:40:50, Xingyu Li wrote: > We noticed that patch 6f861765464f should be probably ported to Linux 6.6 > LTS. Its bug introducing commit is probably 05bdb9965305. The truth is we have always allowed writing to mounted block devices. This is traditional Unix behavior and Linux has been following it. So in principle any kernel before commit 6f861765464f or with CONFIG_BLKDEV_WRITE_MOUNTED=y is prone to the problem. Because unpriviledged users are not generally allowed to write to *any* block device, this is not a security problem. Also note that there are userspace programs (such as filesystem management tools) that need to write to mounted block devices so just disabling CONFIG_BLKDEV_WRITE_MOUNTED is not a generally acceptable option (also for example older versions of mount break if you do this). Hence backporting these changes to stable kernels makes little sense as people are unlikely to be able to use them. CONFIG_BLKDEV_WRITE_MOUNTED is generally useful only for setups doing system fuzzing or tighly controlled locked-down systems where even system administrator is not supposed to get arbitrary priviledges. Honza -- Jan Kara <jack(a)suse.com> SUSE Labs, CR

10 months

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stable-rc: queues: v5.10.233: drivers/of/address.c:272:23: error: implicit declaration of function 'pci_register_io_range'

by Naresh Kamboju

The following build warnings / errors noticed with tinyconfig builds on stable-rc queues 5.10. Build error: --------- kernel/sched/fair.c:8653:13: warning: 'update_nohz_stats' defined but not used [-Wunused-function] 8653 | static bool update_nohz_stats(struct rq *rq) | ^~~~~~~~~~~~~~~~~ drivers/of/address.c: In function 'of_pci_range_to_resource': 272 | err = pci_register_io_range(&np->fwnode, range->cpu_addr,drivers/of/address.c:272:23: error: implicit declaration of function 'pci_register_io_range'; did you mean 'pci_register_driver'? [-Werror=implicit-function-declaration] | ^~~~~~~~~~~~~~~~~~~~~ | pci_register_driver cc1: some warnings being treated as errors Anders bisected this and found, # first bad commit: [00ec41adffcf855c3812cec7b265f43c60752f63] of: address: Use IS_ENABLED() for !CONFIG_PCI arm, arm64, mips, powerpc and riscv: build: * clang-19-tinyconfig * clang-nightly-tinyconfig * gcc-12-tinyconfig * gcc-8-tinyconfig Reported-by: Linux Kernel Functional Testing <lkft(a)linaro.org> Build regression: gcc-compiler-drivers_of_address_c-error-implicit-declaration-of-function-pci_register_io_range-did-you-mean-pci_register_driver metadata: ---- build log: https://qa-reports.linaro.org/lkft/linux-stable-rc-queues-queue_5.10/build/… config: https://storage.tuxsuite.com/public/linaro/lkft/builds/2rwDemGhjGUiyKwSFMek… kernel tree: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git git describe: v5.10.233-115-gdf787b08d487 architectures: arm, arm64, mips, powerpc, riscv history: https://qa-reports.linaro.org/lkft/linux-stable-rc-queues-queue_5.10/build/… steps to reproduce: -------- - tuxmake --runtime podman --target-arch arm64 --toolchain gcc-12 --kconfig tinyconfig -- Linaro LKFT https://lkft.linaro.org

10 months

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Patch "fs: Block writes to mounted block devices" should probably be ported to 6.6 LTS.

by Xingyu Li

Hi, We noticed that patch 6f861765464f should be probably ported to Linux 6.6 LTS. Its bug introducing commit is probably 05bdb9965305. So the vulnerability exists in Linux 6.6 LTS, but the patch is not ported into 6.6 LTS. According to our manual analysis, the commit (05bdb9965305) introduced a vulnerability by replacing `fmode_t` with `blk_mode_t` without preserving the write restrictions on mounted block devices. Specifically, the `sb_open_mode(flags)` macro was changed from using `FMODE_READ` and `FMODE_WRITE` to `BLK_OPEN_READ` and `BLK_OPEN_WRITE`: ```diff #define sb_open_mode(flags) \ - (FMODE_READ | (((flags) & SB_RDONLY) ? 0 : FMODE_WRITE)) + (BLK_OPEN_READ | (((flags) & SB_RDONLY) ? 0 : BLK_OPEN_WRITE)) ``` However, unlike `FMODE_WRITE`, the `BLK_OPEN_WRITE` flag does not inherently prevent unsafe writes to block devices that are mounted by filesystems. This oversight allowed for the possibility of writes directly to the mounted block device, bypassing filesystem controls and potentially leading to data corruption or security breaches. The later patch (commit 6f861765464f43a71462d52026fbddfc858239a5) addressed this vulnerability by introducing the `BLK_OPEN_RESTRICT_WRITES` flag to the `sb_open_mode(flags)` macro: ```diff #define sb_open_mode(flags) \ + (BLK_OPEN_READ | BLK_OPEN_RESTRICT_WRITES | \ + (((flags) & SB_RDONLY) ? 0 : BLK_OPEN_WRITE)) ``` By adding `BLK_OPEN_RESTRICT_WRITES`, the block layer is instructed to block unsafe writes to block devices that are in use by filesystems, restoring the necessary protection that was inadvertently removed in the previous commit. At the same time, we noticed that this patch fixes a bug reported on syzkaller https://syzkaller.appspot.com/bug?extid=c300ab283ba3bc072439, the crash list of this bug contains one report in cbf3a2cb156a(between 6.6-rc4 and 6.6-rc5), so it confirms again that this bug is introduced in 6.6 LTS -- Yours sincerely, Xingyu

10 months

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FAILED: patch "[PATCH] vsock/virtio: discard packets if the transport changes" failed to apply to 5.10-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.10-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.10.y git checkout FETCH_HEAD git cherry-pick -x 2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025012005-supervise-armband-ab52@gregkh' --subject-prefix 'PATCH 5.10.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1 Mon Sep 17 00:00:00 2001 From: Stefano Garzarella <sgarzare(a)redhat.com> Date: Fri, 10 Jan 2025 09:35:07 +0100 Subject: [PATCH] vsock/virtio: discard packets if the transport changes If the socket has been de-assigned or assigned to another transport, we must discard any packets received because they are not expected and would cause issues when we access vsk->transport. A possible scenario is described by Hyunwoo Kim in the attached link, where after a first connect() interrupted by a signal, and a second connect() failed, we can find `vsk->transport` at NULL, leading to a NULL pointer dereference. Fixes: c0cfa2d8a788 ("vsock: add multi-transports support") Cc: stable(a)vger.kernel.org Reported-by: Hyunwoo Kim <v4bel(a)theori.io> Reported-by: Wongi Lee <qwerty(a)theori.io> Closes: https://lore.kernel.org/netdev/Z2LvdTTQR7dBmPb5@v4bel-B760M-AORUS-ELITE-AX/ Signed-off-by: Stefano Garzarella <sgarzare(a)redhat.com> Reviewed-by: Hyunwoo Kim <v4bel(a)theori.io> Signed-off-by: Paolo Abeni <pabeni(a)redhat.com> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index 9acc13ab3f82..51a494b69be8 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -1628,8 +1628,11 @@ void virtio_transport_recv_pkt(struct virtio_transport *t, lock_sock(sk); - /* Check if sk has been closed before lock_sock */ - if (sock_flag(sk, SOCK_DONE)) { + /* Check if sk has been closed or assigned to another transport before + * lock_sock (note: listener sockets are not assigned to any transport) + */ + if (sock_flag(sk, SOCK_DONE) || + (sk->sk_state != TCP_LISTEN && vsk->transport != &t->transport)) { (void)virtio_transport_reset_no_sock(t, skb); release_sock(sk); sock_put(sk);

10 months

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FAILED: patch "[PATCH] vsock/virtio: discard packets if the transport changes" failed to apply to 5.15-stable tree

by gregkh＠linuxfoundation.org

The patch below does not apply to the 5.15-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to <stable(a)vger.kernel.org>. To reproduce the conflict and resubmit, you may use the following commands: git fetch https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/ linux-5.15.y git checkout FETCH_HEAD git cherry-pick -x 2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1 # <resolve conflicts, build, test, etc.> git commit -s git send-email --to '<stable(a)vger.kernel.org>' --in-reply-to '2025012004-rise-cavity-58aa@gregkh' --subject-prefix 'PATCH 5.15.y' HEAD^.. Possible dependencies: thanks, greg k-h ------------------ original commit in Linus's tree ------------------ From 2cb7c756f605ec02ffe562fb26828e4bcc5fdfc1 Mon Sep 17 00:00:00 2001 From: Stefano Garzarella <sgarzare(a)redhat.com> Date: Fri, 10 Jan 2025 09:35:07 +0100 Subject: [PATCH] vsock/virtio: discard packets if the transport changes If the socket has been de-assigned or assigned to another transport, we must discard any packets received because they are not expected and would cause issues when we access vsk->transport. A possible scenario is described by Hyunwoo Kim in the attached link, where after a first connect() interrupted by a signal, and a second connect() failed, we can find `vsk->transport` at NULL, leading to a NULL pointer dereference. Fixes: c0cfa2d8a788 ("vsock: add multi-transports support") Cc: stable(a)vger.kernel.org Reported-by: Hyunwoo Kim <v4bel(a)theori.io> Reported-by: Wongi Lee <qwerty(a)theori.io> Closes: https://lore.kernel.org/netdev/Z2LvdTTQR7dBmPb5@v4bel-B760M-AORUS-ELITE-AX/ Signed-off-by: Stefano Garzarella <sgarzare(a)redhat.com> Reviewed-by: Hyunwoo Kim <v4bel(a)theori.io> Signed-off-by: Paolo Abeni <pabeni(a)redhat.com> diff --git a/net/vmw_vsock/virtio_transport_common.c b/net/vmw_vsock/virtio_transport_common.c index 9acc13ab3f82..51a494b69be8 100644 --- a/net/vmw_vsock/virtio_transport_common.c +++ b/net/vmw_vsock/virtio_transport_common.c @@ -1628,8 +1628,11 @@ void virtio_transport_recv_pkt(struct virtio_transport *t, lock_sock(sk); - /* Check if sk has been closed before lock_sock */ - if (sock_flag(sk, SOCK_DONE)) { + /* Check if sk has been closed or assigned to another transport before + * lock_sock (note: listener sockets are not assigned to any transport) + */ + if (sock_flag(sk, SOCK_DONE) || + (sk->sk_state != TCP_LISTEN && vsk->transport != &t->transport)) { (void)virtio_transport_reset_no_sock(t, skb); release_sock(sk); sock_put(sk);

10 months

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[PATCH] x86/xen: fix SLS mitigation in xen_hypercall_iret()

by Juergen Gross

The backport of upstream patch a2796dff62d6 ("x86/xen: don't do PV iret hypercall through hypercall page") missed to adapt the SLS mitigation config check from CONFIG_MITIGATION_SLS to CONFIG_SLS. Signed-off-by: Juergen Gross <jgross(a)suse.com> --- This patch is meant to be applied to the following stable kernels: - linux-6.6 - linux-6.1 - linux-5.15 - linux-5.10 --- arch/x86/xen/xen-asm.S | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/arch/x86/xen/xen-asm.S b/arch/x86/xen/xen-asm.S index 901b60516683..6231f6efb4ee 100644 --- a/arch/x86/xen/xen-asm.S +++ b/arch/x86/xen/xen-asm.S @@ -221,7 +221,7 @@ SYM_CODE_END(xen_early_idt_handler_array) push %rax mov $__HYPERVISOR_iret, %eax syscall /* Do the IRET. */ -#ifdef CONFIG_MITIGATION_SLS +#ifdef CONFIG_SLS int3 #endif .endm -- 2.43.0

10 months

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[PATCH 5.10] net: fec: remove .ndo_poll_controller to avoid deadlocks

by Denis Arefev

From: Wei Fang <wei.fang(a)nxp.com> commit c2e0c58b25a0a0c37ec643255558c5af4450c9f5 upstream. There is a deadlock issue found in sungem driver, please refer to the commit ac0a230f719b ("eth: sungem: remove .ndo_poll_controller to avoid deadlocks"). The root cause of the issue is that netpoll is in atomic context and disable_irq() is called by .ndo_poll_controller interface of sungem driver, however, disable_irq() might sleep. After analyzing the implementation of fec_poll_controller(), the fec driver should have the same issue. Due to the fec driver uses NAPI for TX completions, the .ndo_poll_controller is unnecessary to be implemented in the fec driver, so fec_poll_controller() can be safely removed. Fixes: 7f5c6addcdc0 ("net/fec: add poll controller function for fec nic") Signed-off-by: Wei Fang <wei.fang(a)nxp.com> Link: https://lore.kernel.org/r/20240511062009.652918-1-wei.fang@nxp.com Signed-off-by: Jakub Kicinski <kuba(a)kernel.org> [Denis: minor fix to resolve merge conflict.] Signed-off-by: Denis Arefev <arefev(a)swemel.ru> --- Backport fix for CVE-2024-38553 Link: https://nvd.nist.gov/vuln/detail/cve-2024-38553 --- drivers/net/ethernet/freescale/fec_main.c | 26 ----------------------- 1 file changed, 26 deletions(-) diff --git a/drivers/net/ethernet/freescale/fec_main.c b/drivers/net/ethernet/freescale/fec_main.c index a591ca0b3778..815062c23708 100644 --- a/drivers/net/ethernet/freescale/fec_main.c +++ b/drivers/net/ethernet/freescale/fec_main.c @@ -3226,29 +3226,6 @@ fec_set_mac_address(struct net_device *ndev, void *p) return 0; } -#ifdef CONFIG_NET_POLL_CONTROLLER -/** - * fec_poll_controller - FEC Poll controller function - * @dev: The FEC network adapter - * - * Polled functionality used by netconsole and others in non interrupt mode - * - */ -static void fec_poll_controller(struct net_device *dev) -{ - int i; - struct fec_enet_private *fep = netdev_priv(dev); - - for (i = 0; i < FEC_IRQ_NUM; i++) { - if (fep->irq[i] > 0) { - disable_irq(fep->irq[i]); - fec_enet_interrupt(fep->irq[i], dev); - enable_irq(fep->irq[i]); - } - } -} -#endif - static inline void fec_enet_set_netdev_features(struct net_device *netdev, netdev_features_t features) { @@ -3322,9 +3299,6 @@ static const struct net_device_ops fec_netdev_ops = { .ndo_tx_timeout = fec_timeout, .ndo_set_mac_address = fec_set_mac_address, .ndo_do_ioctl = fec_enet_ioctl, -#ifdef CONFIG_NET_POLL_CONTROLLER - .ndo_poll_controller = fec_poll_controller, -#endif .ndo_set_features = fec_set_features, }; -- 2.43.0

10 months

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Fwd: [PATCH] nfsd: add list_head nf_gc to struct nfsd_file

by Chuck Lever

Hi Sasha, Greg - This is upstream commit 8e6e2ffa6569a205f1805cbaeca143b556581da6. I've received a request for it to be applied specifically to v5.15.y. Can you apply it to all LTS kernels back to v5.10 ? -------- Forwarded Message -------- Subject: [PATCH] nfsd: add list_head nf_gc to struct nfsd_file Date: Wed, 10 Jul 2024 10:40:35 -0400 From: Youzhong Yang <youzhong(a)gmail.com> To: jlayton(a)kernel.org, chuck.lever(a)oracle.com, linux-nfs(a)vger.kernel.org, youzhong(a)gmail.com nfsd_file_put() in one thread can race with another thread doing garbage collection (running nfsd_file_gc() -> list_lru_walk() -> nfsd_file_lru_cb()): * In nfsd_file_put(), nf->nf_ref is 1, so it tries to do nfsd_file_lru_add(). * nfsd_file_lru_add() returns true (with NFSD_FILE_REFERENCED bit set) * garbage collector kicks in, nfsd_file_lru_cb() clears REFERENCED bit and returns LRU_ROTATE. * garbage collector kicks in again, nfsd_file_lru_cb() now decrements nf->nf_ref to 0, runs nfsd_file_unhash(), removes it from the LRU and adds to the dispose list [list_lru_isolate_move(lru, &nf->nf_lru, head)] * nfsd_file_put() detects NFSD_FILE_HASHED bit is cleared, so it tries to remove the 'nf' from the LRU [if (!nfsd_file_lru_remove(nf))]. The 'nf' has been added to the 'dispose' list by nfsd_file_lru_cb(), so nfsd_file_lru_remove(nf) simply treats it as part of the LRU and removes it, which leads to its removal from the 'dispose' list. * At this moment, 'nf' is unhashed with its nf_ref being 0, and not on the LRU. nfsd_file_put() continues its execution [if (refcount_dec_and_test(&nf->nf_ref))], as nf->nf_ref is already 0, nf->nf_ref is set to REFCOUNT_SATURATED, and the 'nf' gets no chance of being freed. nfsd_file_put() can also race with nfsd_file_cond_queue(): * In nfsd_file_put(), nf->nf_ref is 1, so it tries to do nfsd_file_lru_add(). * nfsd_file_lru_add() sets REFERENCED bit and returns true. * Some userland application runs 'exportfs -f' or something like that, which triggers __nfsd_file_cache_purge() -> nfsd_file_cond_queue(). * In nfsd_file_cond_queue(), it runs [if (!nfsd_file_unhash(nf))], unhash is done successfully. * nfsd_file_cond_queue() runs [if (!nfsd_file_get(nf))], now nf->nf_ref goes to 2. * nfsd_file_cond_queue() runs [if (nfsd_file_lru_remove(nf))], it succeeds. * nfsd_file_cond_queue() runs [if (refcount_sub_and_test(decrement, &nf->nf_ref))] (with "decrement" being 2), so the nf->nf_ref goes to 0, the 'nf' is added to the dispose list [list_add(&nf->nf_lru, dispose)] * nfsd_file_put() detects NFSD_FILE_HASHED bit is cleared, so it tries to remove the 'nf' from the LRU [if (!nfsd_file_lru_remove(nf))], although the 'nf' is not in the LRU, but it is linked in the 'dispose' list, nfsd_file_lru_remove() simply treats it as part of the LRU and removes it. This leads to its removal from the 'dispose' list! * Now nf->ref is 0, unhashed. nfsd_file_put() continues its execution and set nf->nf_ref to REFCOUNT_SATURATED. As shown in the above analysis, using nf_lru for both the LRU list and dispose list can cause the leaks. This patch adds a new list_head nf_gc in struct nfsd_file, and uses it for the dispose list. This does not fix the nfsd_file leaking issue completely. Signed-off-by: Youzhong Yang <youzhong(a)gmail.com> --- fs/nfsd/filecache.c | 18 ++++++++++-------- fs/nfsd/filecache.h | 1 + 2 files changed, 11 insertions(+), 8 deletions(-) diff --git a/fs/nfsd/filecache.c b/fs/nfsd/filecache.c index ad9083ca144b..22ebd7fb8639 100644 --- a/fs/nfsd/filecache.c +++ b/fs/nfsd/filecache.c @@ -216,6 +216,7 @@ nfsd_file_alloc(struct net *net, struct inode *inode, unsigned char need, return NULL; INIT_LIST_HEAD(&nf->nf_lru); + INIT_LIST_HEAD(&nf->nf_gc); nf->nf_birthtime = ktime_get(); nf->nf_file = NULL; nf->nf_cred = get_current_cred(); @@ -393,8 +394,8 @@ nfsd_file_dispose_list(struct list_head *dispose) struct nfsd_file *nf; while (!list_empty(dispose)) { - nf = list_first_entry(dispose, struct nfsd_file, nf_lru); - list_del_init(&nf->nf_lru); + nf = list_first_entry(dispose, struct nfsd_file, nf_gc); + list_del_init(&nf->nf_gc); nfsd_file_free(nf); } } @@ -411,12 +412,12 @@ nfsd_file_dispose_list_delayed(struct list_head *dispose) { while(!list_empty(dispose)) { struct nfsd_file *nf = list_first_entry(dispose, - struct nfsd_file, nf_lru); + struct nfsd_file, nf_gc); struct nfsd_net *nn = net_generic(nf->nf_net, nfsd_net_id); struct nfsd_fcache_disposal *l = nn->fcache_disposal; spin_lock(&l->lock); - list_move_tail(&nf->nf_lru, &l->freeme); + list_move_tail(&nf->nf_gc, &l->freeme); spin_unlock(&l->lock); svc_wake_up(nn->nfsd_serv); } @@ -503,7 +504,8 @@ nfsd_file_lru_cb(struct list_head *item, struct list_lru_one *lru, /* Refcount went to zero. Unhash it and queue it to the dispose list */ nfsd_file_unhash(nf); - list_lru_isolate_move(lru, &nf->nf_lru, head); + list_lru_isolate(lru, &nf->nf_lru); + list_add(&nf->nf_gc, head); this_cpu_inc(nfsd_file_evictions); trace_nfsd_file_gc_disposed(nf); return LRU_REMOVED; @@ -578,7 +580,7 @@ nfsd_file_cond_queue(struct nfsd_file *nf, struct list_head *dispose) /* If refcount goes to 0, then put on the dispose list */ if (refcount_sub_and_test(decrement, &nf->nf_ref)) { - list_add(&nf->nf_lru, dispose); + list_add(&nf->nf_gc, dispose); trace_nfsd_file_closing(nf); } } @@ -654,8 +656,8 @@ nfsd_file_close_inode_sync(struct inode *inode) nfsd_file_queue_for_close(inode, &dispose); while (!list_empty(&dispose)) { - nf = list_first_entry(&dispose, struct nfsd_file, nf_lru); - list_del_init(&nf->nf_lru); + nf = list_first_entry(&dispose, struct nfsd_file, nf_gc); + list_del_init(&nf->nf_gc); nfsd_file_free(nf); } } diff --git a/fs/nfsd/filecache.h b/fs/nfsd/filecache.h index c61884def906..3fbec24eea6c 100644 --- a/fs/nfsd/filecache.h +++ b/fs/nfsd/filecache.h @@ -44,6 +44,7 @@ struct nfsd_file { struct nfsd_file_mark *nf_mark; struct list_head nf_lru; + struct list_head nf_gc; struct rcu_head nf_rcu; ktime_t nf_birthtime; }; -- 2.45.2

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[PATCH 6.1.y] regmap: fix wrong backport

by Tzung-Bi Shih

48dc44f3c1af ("regmap: detach regmap from dev on regmap_exit") wrongly backported upstream commit 3061e170381a. It should patch regmap_exit() instead of regmap_reinit_cache(). Fixes: 48dc44f3c1af ("regmap: detach regmap from dev on regmap_exit") Signed-off-by: Tzung-Bi Shih <tzungbi(a)kernel.org> --- drivers/base/regmap/regmap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/base/regmap/regmap.c b/drivers/base/regmap/regmap.c index 8748cea3bc38..f0e314abcafc 100644 --- a/drivers/base/regmap/regmap.c +++ b/drivers/base/regmap/regmap.c @@ -1513,7 +1513,6 @@ int regmap_reinit_cache(struct regmap *map, const struct regmap_config *config) { int ret; - regmap_detach_dev(map->dev, map); regcache_exit(map); regmap_debugfs_exit(map); @@ -1548,6 +1547,7 @@ void regmap_exit(struct regmap *map) { struct regmap_async *async; + regmap_detach_dev(map->dev, map); regcache_exit(map); regmap_debugfs_exit(map); regmap_range_exit(map); -- 2.48.0.rc2.279.g1de40edade-goog

10 months

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