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[PATCH OLK-6.6] params: fix charp corruption on allocation failure
by Pan Taixi 22 Sep '26

22 Sep '26

mainline inclusion from mainline-v7.3-rc1 commit 3dfaae04243cde460d82dfc2a7dd0bb6664d20ae category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/18886 CVE: CVE-2026-89552 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- param_set_charp() stores charp parameters in allocated memory after slab is available, and releases the previous value when the parameter is updated. The previous value is released before the replacement allocation succeeds. If kmalloc_parameter() fails, the setter returns -ENOMEM with the parameter left as NULL. Failing zswap's compressor update before zswap is initialized can later trigger: BUG: kernel NULL pointer dereference, address: 0000000000000000 RIP: 0010:strcmp+0x10/0x30 Call Trace: zswap_setup+0x3b1/0x490 zswap_enabled_param_set+0x5b/0xa0 param_attr_store+0x93/0xe0 module_attr_store+0x1c/0x30 kernfs_fop_write_iter+0x116/0x1f0 Allocate and copy the replacement first, then replace the parameter value only after allocation succeeds. Fixes: e180a6b7759a ("param: fix charp parameters set via sysfs") Cc: stable(a)vger.kernel.org Upstream commit 3dfaae04243cde460d82dfc2a7dd0bb6664d20ae Signed-off-by: Jiacheng Yu <yujiacheng3(a)huawei.com> Reviewed-by: Petr Pavlu <petr.pavlu(a)suse.com> Signed-off-by: Petr Pavlu <petr.pavlu(a)suse.com> Conflicts: kernel/params.c [The upstream hunk context relies on e180a6b7759a ("param: fix charp parameters set via sysfs"), which is absent in this tree; keep the existing strlen() length check and use strcpy(tmp, val) with strlen(val) + 1 for the allocation.] Co-authored-by: BackportAgent@a:deepseek-v4.1-flash Signed-off-by: Hulk Robot <hulkrobot(a)huawei.com> Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5(a)huawei.com> Signed-off-by: Pan Taixi <pantaixi1(a)huawei.com> --- kernel/params.c | 15 +++++++++------ 1 file changed, 9 insertions(+), 6 deletions(-) diff --git a/kernel/params.c b/kernel/params.c index 9d09ea99363f..d7afd70cfe45 100644 --- a/kernel/params.c +++ b/kernel/params.c @@ -262,26 +262,29 @@ int param_set_uint_minmax(const char *val, const struct kernel_param *kp, } EXPORT_SYMBOL_GPL(param_set_uint_minmax); int param_set_charp(const char *val, const struct kernel_param *kp) { + char *tmp; + if (strlen(val) > 1024) { pr_err("%s: string parameter too long\n", kp->name); return -ENOSPC; } - maybe_kfree_parameter(*(char **)kp->arg); - /* This is a hack. We can't kmalloc in early boot, and we * don't need to; this mangled commandline is preserved. */ if (slab_is_available()) { - *(char **)kp->arg = kmalloc_parameter(strlen(val)+1); - if (!*(char **)kp->arg) + tmp = kmalloc_parameter(strlen(val) + 1); + if (!tmp) return -ENOMEM; - strcpy(*(char **)kp->arg, val); + strcpy(tmp, val); } else - *(const char **)kp->arg = val; + tmp = (char *)val; + + maybe_kfree_parameter(*(char **)kp->arg); + *(char **)kp->arg = tmp; return 0; } EXPORT_SYMBOL(param_set_charp); -- 2.34.1

2 1

[PATCH OLK-6.6] xarray: honor XA_FLAGS_ACCOUNT in xas_split_alloc()
by Pan Taixi 22 Sep '26

22 Sep '26

From: Zi Yan <ziy(a)nvidia.com> stable inclusion from stable-v6.6.157 commit 6c1a8685be6a7aa923114b0bd99be100ac7932d5 category: bugfix bugzilla: https://atomgit.com/openeuler/kernel/issues/9956 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 789763523fb43cdc328de5cb5dcd19240ccf90d8 upstream. XArray operations that allocate xa_nodes, such as xas_nomem() and xas_alloc(), add __GFP_ACCOUNT when the array has XA_FLAGS_ACCOUNT set. This charges the allocated memory and avoids the workingset convergence issue described by commit 7b785645e8f13 ("mm: fix page cache convergence regression"). xas_split_alloc() does not add _GFP_ACCOUNT when XA_FLAGS_ACCOUNT is present. Fix it. Link: https://lore.kernel.org/20260804-add-gfp_account-to-xas_split_alloc-v3-2-38… Fixes: 6b24ca4a1a8d ("mm: Use multi-index entries in the page cache") Signed-off-by: Zi Yan <ziy(a)nvidia.com> Reviewed-by: Lorenzo Stoakes (ARM) <ljs(a)kernel.org> Acked-by: Johannes Weiner <hannes(a)cmpxchg.org> Cc: Baolin Wang <baolin.wang(a)linux.alibaba.com> Cc: Barry Song <baohua(a)kernel.org> Cc: David Hildenbrand <david(a)kernel.org> Cc: Dev Jain <dev.jain(a)arm.com> Cc: Lance Yang <lance.yang(a)linux.dev> Cc: Liam R. Howlett <liam(a)infradead.org> Cc: Matthew Wilcox (Oracle) <willy(a)infradead.org> Cc: Ryan Roberts <ryan.roberts(a)arm.com> Cc: William Kucharski <william.kucharski(a)oracle.com> Cc: <stable(a)vger.kernel.org> Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Conflicts: lib/xarray.c [Context conflicts due to merged commit 0d05e9423e4c ("xarray: add xas_try_split() to split a multi-index entry")] Signed-off-by: Pan Taixi <pantaixi1(a)huawei.com> --- lib/xarray.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/lib/xarray.c b/lib/xarray.c index ab56835d4ed0..f70f3fd5dc8a 100644 --- a/lib/xarray.c +++ b/lib/xarray.c @@ -1045,10 +1045,13 @@ void xas_split_alloc(struct xa_state *xas, void *entry, unsigned int order, if (WARN_ON(xas->xa_shift + 2 * XA_CHUNK_SHIFT <= order)) goto nomem; if (xas->xa_shift + XA_CHUNK_SHIFT > order) return; + if (xas->xa->xa_flags & XA_FLAGS_ACCOUNT) + gfp |= __GFP_ACCOUNT; + do { struct xa_node *node; node = kmem_cache_alloc_lru(radix_tree_node_cachep, xas->xa_lru, gfp); if (!node) -- 2.34.1

2 1

[PATCH OLK-6.6 V1] media: v4l2-fwnode: Fix fwnode leak in v4l2_fwnode_parse_link
by Yao Yiqi 22 Sep '26

22 Sep '26

From: Biren Pandya <birenpandya(a)gmail.com> stable inclusion from stable-v6.6.157 commit ef609b3ce456f021320fee2fb7e45094a3ccf232 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19081 CVE: CVE-2026-89872 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit a6e86efd7f85e519bf48417f41923f8bd51f1597 upstream. In v4l2_fwnode_parse_link(), the remote endpoint fwnode reference is acquired using fwnode_graph_get_remote_endpoint(). This reference is properly released in the error paths, but it is leaked on the success path. Add the missing fwnode_handle_put() before returning 0 to prevent the reference leak. Signed-off-by: Biren Pandya <birenpandya(a)gmail.com> Fixes: ca50c197bd96 ("[media] v4l: fwnode: Support generic fwnode for parsing standardised properties") Cc: stable(a)vger.kernel.org [Sakari Ailus: Fix subject prefix and coding style a little.] Signed-off-by: Sakari Ailus <sakari.ailus(a)linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Yao Yiqi <yaoyiqi3(a)huawei.com> --- drivers/media/v4l2-core/v4l2-fwnode.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/media/v4l2-core/v4l2-fwnode.c b/drivers/media/v4l2-core/v4l2-fwnode.c index 519eaad0af5f..7a9456240fe5 100644 --- a/drivers/media/v4l2-core/v4l2-fwnode.c +++ b/drivers/media/v4l2-core/v4l2-fwnode.c @@ -582,6 +582,8 @@ int v4l2_fwnode_parse_link(struct fwnode_handle *fwnode, if (!link->remote_node) goto err_put_remote_endpoint; + fwnode_handle_put(fwnode); + return 0; err_put_remote_endpoint: -- 2.34.1

2 1

[PATCH OLK-6.6 V1] media: tda18250: fix possible integer overflow
by Yao Yiqi 22 Sep '26

22 Sep '26

From: Ilya Krutskih <devsec(a)tpz.ru> stable inclusion from stable-v6.6.157 commit 593b1172e5d548581dfdb9a63713088f5dfab255 category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19082 CVE: CVE-2026-89876 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 6dd8e257f7cafda7fbf10d81b3c55c9bba4825f4 upstream. Integer overflow may occur, when variable exp equals to zero. Result of shift 1 << (exp - 1) may then leads to undefined behavior. Fixes: 148abd3b5b14 ("media: tda18250: support for new silicon tuner") Cc: stable(a)vger.kernel.org Signed-off-by: Ilya Krutskih <devsec(a)tpz.ru> Signed-off-by: Hans Verkuil <hverkuil+cisco(a)kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Yao Yiqi <yaoyiqi3(a)huawei.com> --- drivers/media/tuners/tda18250.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/media/tuners/tda18250.c b/drivers/media/tuners/tda18250.c index 32ea473f3f49..c6c1d1cdaa4c 100644 --- a/drivers/media/tuners/tda18250.c +++ b/drivers/media/tuners/tda18250.c @@ -440,8 +440,8 @@ static int tda18250_pll_calc(struct dvb_frontend *fe, u8 *rdiv, goto err; exp = (uval & 0x70) >> 4; - if (exp > 5) - exp = 0; + if (exp == 0 || exp > 5) + exp = 1; lopd = 1 << (exp - 1); scale = uval & 0x0f; fvco = lopd * scale * ((c->frequency / 1000) + dev->if_frequency); -- 2.34.1

2 1

[PATCH OLK-6.6] perf/x86/intel: Fix kernel address leakages in LBR stack
by Luo Gengkun 22 Sep '26

22 Sep '26

From: Dapeng Mi <dapeng1.mi(a)linux.intel.com> stable inclusion from stable-v6.6.157 commit ca19a175e89b7de604fab736436cbab74030b47a category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19105 CVE: CVE-2026-89984 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… ---------------------------------------------------------------------- commit e2b0575900ff72aa82748af96e7bd564ade5157a upstream. Before Arch LBR gained CPL filtering support, a user-only branch stack could still contain kernel addresses. As a result, kernel branch records may be exposed to user space even when PERF_SAMPLE_BRANCH_USER is requested. For example, on Intel Tiger Lake, the following command can still report SYSRET/ERET entries with kernel-space from addresses: $ ./perf record -e cycles:p -o - --branch-filter any,save_type,u -- \ ./perf bench syscall basic --loop 1000 | \ ./perf script -i - --fields brstack|tr ' ' '\n'| \ grep -E '0x[89a-f][0-9a-f]{15}' Total time: 0.000 [sec] 0.219000 usecs/op 4,566,210 ops/sec [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.551 MB - ] 0xffffffff93c001c8/0x7f12a2b1d647/P/-/-/16959/SYSRET/- 0xffffffff93c001c8/0x7f12a2b1d5c2/P/-/-/17535/SYSRET/- 0xffffffff93c01928/0x7f12a2861000/P/-/-/6719/ERET/- 0xffffffff93c01928/0x7f12a297a000/P/-/-/8575/ERET/- The problem is that intel_pmu_lbr_filter() does not fully validate the privilege level of sampled entries. It filters some mismatches based on the branch type and the to address, but it does not reject entries whose from address violates the requested branch privilege filter. Fix this by extending software filtering to validate both from and to addresses against br_sel. Any LBR entry contains kernel address does not match the requested user filter is dropped. This prevents kernel addresses from appearing in user-only branch stacks. Fixes: 47125db27e47 ("perf/x86/intel/lbr: Support Architectural LBR") Reported-by: Ian Rogers <irogers(a)google.com> Signed-off-by: Dapeng Mi <dapeng1.mi(a)linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz(a)infradead.org> Cc: stable(a)vger.kernel.org Link: https://patch.msgid.link/20260616044654.3468742-5-dapeng1.mi@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Luo Gengkun <luogengkun2(a)huawei.com> --- arch/x86/events/intel/lbr.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c index 5f677447b812..5bb76f13edbb 100644 --- a/arch/x86/events/intel/lbr.c +++ b/arch/x86/events/intel/lbr.c @@ -1201,7 +1201,7 @@ intel_pmu_lbr_filter(struct cpu_hw_events *cpuc) { u64 from, to; int br_sel = cpuc->br_sel; - int i, j, type, to_plm; + int i, j, type, from_plm, to_plm; bool compress = false; /* if sampling all branches, then nothing to filter */ @@ -1233,8 +1233,14 @@ intel_pmu_lbr_filter(struct cpu_hw_events *cpuc) type |= X86_BR_NO_TX; } - /* if type does not correspond, then discard */ - if (type == X86_BR_NONE || (br_sel & type) != type) { + from_plm = kernel_ip(from) ? X86_BR_KERNEL : X86_BR_USER; + /* + * If type does not correspond, then discard. + * Specifically reject entries whose from address is in + * kernel space when only X86_BR_USER is requested. + */ + if (type == X86_BR_NONE || (br_sel & type) != type || + (!(br_sel & X86_BR_KERNEL) && (from_plm & X86_BR_KERNEL))) { cpuc->lbr_entries[i].from = 0; compress = true; } -- 2.34.1

2 1

[OLK-5.10] fuse: fix invalidate lock leak on open O_TRUNC DAX failure
by Yang Erkun 22 Sep '26

22 Sep '26

From: Baokun Li <libaokun(a)linux.alibaba.com> mainline inclusion from mainline-v7.3-rc1 commit a927f1867e61b78f39f9da0bbba3c98c2ca151fe category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/18697 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- fuse_open() takes filemap_invalidate_lock() for a DAX truncate (dax_truncate = true) and releases it before the out_inode_unlock label. But when fuse_dax_break_layouts() fails, the goto out_inode_unlock skips the unlock and leaks the rwsem, so any later fault or truncate on the file stalls on the stale lock. fuse_dax_break_layouts() can fail with -ERESTARTSYS when a signal interrupts the wait for busy DAX pages to drain: open("file", O_RDWR | O_TRUNC) └─ fuse_open() ├─ filemap_invalidate_lock() # dax_truncate └─ fuse_dax_break_layouts() └─ dax_break_layout() └─ wait_page_idle() # TASK_INTERRUPTIBLE └─ fuse_wait_dax_page() # unlock, schedule, re-lock └─ signal → -ERESTARTSYS goto out_inode_unlock # <- lock leaked Fix this by moving filemap_invalidate_unlock() below the label so that all error paths release the lock, and rename the label to out_unlock as it now covers more than just the inode lock. Fixes: 2fdbb8dd0155 ("fuse: fix deadlock between atomic O_TRUNC and page invalidation") Cc: stable(a)vger.kernel.org # v6.0+ Signed-off-by: Baokun Li <libaokun(a)linux.alibaba.com> Signed-off-by: Miklos Szeredi <mszeredi(a)redhat.com> Conflicts: fs/fuse/file.c [The target tree still uses i_mmap_sem instead of filemap_invalidate_lock(), so relocate up_write(&i_mmap_sem) below the renamed out_unlock label.] Signed-off-by: Yang Erkun <yangerkun(a)huawei.com> --- fs/fuse/file.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/fs/fuse/file.c b/fs/fuse/file.c index 87c8272d0e17..f41c55484313 100644 --- a/fs/fuse/file.c +++ b/fs/fuse/file.c @@ -245,7 +245,7 @@ int fuse_open_common(struct inode *inode, struct file *file, bool isdir) down_write(&get_fuse_inode(inode)->i_mmap_sem); err = fuse_dax_break_layouts(inode, 0, 0); if (err) - goto out_inode_unlock; + goto out_unlock; } if (is_wb_truncate || dax_truncate) @@ -265,6 +265,7 @@ int fuse_open_common(struct inode *inode, struct file *file, bool isdir) else if (!(ff->open_flags & FOPEN_KEEP_CACHE)) invalidate_inode_pages2(inode->i_mapping); } +out_unlock: if (dax_truncate) up_write(&get_fuse_inode(inode)->i_mmap_sem); -- 2.52.0

1 0

[PATCH OLK-5.10 1/2] media: cec: cec-adap: always cancel work in cec_transmit_msg_fh
by Chen Jinghuang 22 Sep '26

22 Sep '26

From: Hans Verkuil <hverkuil-cisco(a)xs4all.nl> mainline inclusion from mainline-v7.3-rc1 commit 9fe2816816a3c765dff3b88af5b5c3d9bbb911ce category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19090 CVE: CVE-2026-89899 Reference: https://web.git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/comm… -------------------------------- Do not check for !data->completed, just always call cancel_delayed_work_sync(). This fixes a small race condition. Signed-off-by: Hans Verkuil <hverkuil-cisco(a)xs4all.nl> Reported-by: Yang, Chenyuan <cy54(a)illinois.edu> Closes: https://lore.kernel.org/linux-media/PH7PR11MB57688E64ADE4FE82E658D86DA09EA@… Fixes: 490d84f6d73c ("media: cec: forgot to cancel delayed work") Signed-off-by: Mauro Carvalho Chehab <mchehab(a)kernel.org> Signed-off-by: Chen jinghuang <chenjinghuang2(a)huawei.com> --- drivers/media/cec/core/cec-adap.c | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) diff --git a/drivers/media/cec/core/cec-adap.c b/drivers/media/cec/core/cec-adap.c index eed962a9ff01..513e8739bfcb 100644 --- a/drivers/media/cec/core/cec-adap.c +++ b/drivers/media/cec/core/cec-adap.c @@ -913,8 +913,7 @@ int cec_transmit_msg_fh(struct cec_adapter *adap, struct cec_msg *msg, */ mutex_unlock(&adap->lock); wait_for_completion_killable(&data->c); - if (!data->completed) - cancel_delayed_work_sync(&data->work); + cancel_delayed_work_sync(&data->work); mutex_lock(&adap->lock); /* Cancel the transmit if it was interrupted */ -- 2.34.1

2 2

[PATCH OLK-5.10 V1 0/3] Fix CVE-2026-90329
by Yao Yiqi 22 Sep '26

22 Sep '26

CVE-2026-90329 fix has 2 dependencies. Dmitry Torokhov (2): HID: split apart hid_device_probe to make logic more apparent HID: ensure timely release of driver-allocated resources Yousef Alhouseen (1): HID: synchronize input before cleaning up a failed probe drivers/hid/hid-core.c | 120 +++++++++++++++++++++++++---------------- include/linux/hid.h | 1 + 2 files changed, 74 insertions(+), 47 deletions(-) -- 2.34.1

2 4

[PATCH OLK-6.6 v4] bpf, cgroup: Fix invalid storage access after __cgroup_bpf_attach failed
by Pu Lehui 22 Sep '26

22 Sep '26

stable inclusion from stable-v6.6.157 commit e26db0d636e4c24a6b16683ea95cf5077c64d74b category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19474 CVE: CVE-2026-90313 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 6655c409707ec8ce9ce0850ffe4fe02331fd4d9c ] A potential invalid storage access issue can occur after replacing a cgroup bpf prog. This occurs in the following scenario: 1. prog1 with storage is attached to a cgroup in multi-attach mode. 2. prog1 is replaced with prog2 using BPF_F_REPLACE in multi-attach mode, but fails midway (e.g. in bpf_trampoline_link_cgroup_shim or update_effective_progs). 3. A new prog3 is attached to the cgroup in multi-attach mode. The reason is that __cgroup_bpf_attach overwrites pl->storage with the new storage prior to attachment completion. When attachment fails midway, the cleanup path calls bpf_cgroup_storages_free(new_storage) to free the newly allocated storage, but fails to restore pl->storage back to old_storage. Consequently, the still-active prog1 holds invalid or dangling storage pointers, leading to an invalid memory access when prog1 executes and calls bpf_get_local_storage. Additionally, original pl->flags and cgrp->bpf.flags[atype] are left unrestored. Fix this by saving old_pl_flags, old_storage, and old_flags prior to the update, and properly restoring all of them in the cleanup path on error. Fixes: 7d9c3427894f ("bpf: Make cgroup storages shared between programs on the same cgroup") Reported-by: Sashiko <sashiko-bot(a)kernel.org> Signed-off-by: Pu Lehui <pulehui(a)huawei.com> Signed-off-by: Andrii Nakryiko <andrii(a)kernel.org> Reviewed-by: Emil Tsalapatis <emil(a)etsalapatis.com> Link: https://lore.kernel.org/bpf/20260803013934.4036646-1-pulehui@huaweicloud.com Signed-off-by: Sasha Levin <sashal(a)kernel.org> Conflicts: kernel/bpf/cgroup.c [Commit bc8023ef3b11 (bpf: Allow pre-ordering for bpf cgroup progs) is not backported, so struct bpf_prog_list has no flags field in this tree. Drop the pl->flags save/restore added by the fix and keep restoring pl->storage and cgrp->bpf.flags[atype].] Co-authored-by: BackportAgent@a:deepseek-v4.1-flash Signed-off-by: Hulk Robot <hulkrobot(a)huawei.com> Signed-off-by: Zhang Xiaoxu <zhangxiaoxu5(a)huawei.com> Signed-off-by: Pu Lehui <pulehui(a)huawei.com> --- kernel/bpf/cgroup.c | 6 ++++++ 1 file changed, 6 insertions(+) diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index d72413d9b9bc..7dd59db00858 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -651,8 +651,10 @@ static int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *old_prog = NULL; struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE] = {}; struct bpf_cgroup_storage *new_storage[MAX_BPF_CGROUP_STORAGE_TYPE] = {}; + struct bpf_cgroup_storage *old_storage[MAX_BPF_CGROUP_STORAGE_TYPE] = {}; struct bpf_prog *new_prog = prog ? : link->link.prog; enum cgroup_bpf_attach_type atype; + u32 old_flags; struct bpf_prog_list *pl; struct hlist_head *progs; int err; @@ -704,6 +706,7 @@ static int __cgroup_bpf_attach(struct cgroup *cgrp, if (pl) { old_prog = pl->prog; + bpf_cgroup_storages_assign(old_storage, pl->storage); } else { struct hlist_node *last = NULL; @@ -726,6 +729,7 @@ static int __cgroup_bpf_attach(struct cgroup *cgrp, pl->prog = prog; pl->link = link; bpf_cgroup_storages_assign(pl->storage, storage); + old_flags = cgrp->bpf.flags[atype]; cgrp->bpf.flags[atype] = saved_flags; if (type == BPF_LSM_CGROUP) { @@ -756,12 +760,14 @@ static int __cgroup_bpf_attach(struct cgroup *cgrp, if (old_prog) { pl->prog = old_prog; pl->link = NULL; + bpf_cgroup_storages_assign(pl->storage, old_storage); } bpf_cgroup_storages_free(new_storage); if (!old_prog) { hlist_del(&pl->node); kfree(pl); } + cgrp->bpf.flags[atype] = old_flags; return err; } -- 2.34.1

2 1

[PATCH OLK-6.6] LoongArch: Avoid preempt count underflow without probe
by Tengda Wu 22 Sep '26

22 Sep '26

From: Jérémy Jean <Jeremy.Jean(a)oss.cyber.gouv.fr> stable inclusion from stable-v6.6.157 commit ff40e597d5d98c0c45a4d09df8177202fac9520e category: bugfix bugzilla: https://atomgit.com/src-openeuler/kernel/issues/19585 CVE: CVE-2026-89902 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 72ce4b24676e8b3b75376c4c559dd81c1ac52d5a upstream. LoongArch uses break 11 for the breakpoint placed after an instruction that Kprobes executes out of line. Since userspace can issue the same break instruction, do_bp() can reach kprobe_singlestep_handler() when there is no current probe. The handler actually returns false in this case, but it first calls preempt_enable_no_resched(). The corresponding preempt_disable() is done by kprobe_breakpoint_handler() on a real Kprobe hit, so it has not run here. As a result, an ordinary userspace breakpoint (code 11) underflows the current task's preempt count. This also makes in_interrupt() return true until the task schedules. One visible consequence is the socket cgroup attribution: cgroup_sk_alloc() treats the allocation as interrupt context and assigns the socket to the root cgroup. A socket opened from the SIGTRAP handler can then avoid a BPF_CGROUP_INET_SOCK_CREATE policy attached to the task's own cgroup. Return as soon as kprobe_running() reports no active probe. The same check has appeared in [PATCH v10 2/4] of the original LoongArch Kprobes series, but was dropped before the feature reached mainline. Cc: stable(a)vger.kernel.org Fixes: 6d4cc40fb5f5 ("LoongArch: Add kprobes support") Link: https://lore.kernel.org/loongarch/1670575981-14389-3-git-send-email-yangtie… Assisted-by: Codex:gpt-5 Signed-off-by: Jérémy Jean <Jeremy.Jean(a)oss.cyber.gouv.fr> Signed-off-by: Huacai Chen <chenhuacai(a)loongson.cn> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Tengda Wu <wutengda2(a)huawei.com> --- arch/loongarch/kernel/kprobes.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/loongarch/kernel/kprobes.c b/arch/loongarch/kernel/kprobes.c index ea98b6a3e201..3e87bd03f3f7 100644 --- a/arch/loongarch/kernel/kprobes.c +++ b/arch/loongarch/kernel/kprobes.c @@ -273,6 +273,9 @@ bool kprobe_singlestep_handler(struct pt_regs *regs) struct kprobe_ctlblk *kcb = get_kprobe_ctlblk(); unsigned long addr = instruction_pointer(regs); + if (!cur) + return false; + if (cur && (kcb->kprobe_status & (KPROBE_HIT_SS | KPROBE_REENTER)) && ((unsigned long)&cur->ainsn.insn[1] == addr)) { restore_local_irqflag(kcb, regs); -- 2.34.1

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