October 2025 - Linux-stable-mirror

[PATCH] powerpc/pseries: add input size check in ofdt_write

by Miaoqian Lin

A malicious user could pass an arbitrarily bad value to memdup_user_nul(), potentially causing kernel crash. This follows the same pattern as commit ee76746387f6 ("netdevsim: prevent bad user input in nsim_dev_health_break_write()") Found via static analysis and code review. Fixes: 3783225130f0 ("powerpc/pseries: use memdup_user_nul") Cc: stable(a)vger.kernel.org Signed-off-by: Miaoqian Lin <linmq006(a)gmail.com> --- arch/powerpc/platforms/pseries/reconfig.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/arch/powerpc/platforms/pseries/reconfig.c b/arch/powerpc/platforms/pseries/reconfig.c index 599bd2c78514..b6bc1d8b2207 100644 --- a/arch/powerpc/platforms/pseries/reconfig.c +++ b/arch/powerpc/platforms/pseries/reconfig.c @@ -366,6 +366,9 @@ static ssize_t ofdt_write(struct file *file, const char __user *buf, size_t coun if (rv) return rv; + if (count == 0 || count > PAGE_SIZE) + return -EINVAL; + kbuf = memdup_user_nul(buf, count); if (IS_ERR(kbuf)) return PTR_ERR(kbuf); -- 2.39.5 (Apple Git-154)

1 week, 4 days

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[PATCH v2] net: usb: asix_devices: Check return value of usbnet_get_endpoints

by Miaoqian Lin

The code did not check the return value of usbnet_get_endpoints. Add checks and return the error if it fails to transfer the error. Found via static anlaysis and this is similar to commit 07161b2416f7 ("sr9800: Add check for usbnet_get_endpoints"). Fixes: 933a27d39e0e ("USB: asix - Add AX88178 support and many other changes") Fixes: 2e55cc7210fe ("[PATCH] USB: usbnet (3/9) module for ASIX Ethernet adapters") Cc: stable(a)vger.kernel.org Signed-off-by: Miaoqian Lin <linmq006(a)gmail.com> --- - v1:http://lore.kernel.org/all/20250830103743.2118777-1-linmq006@gmail.com changes in v2: - fix the blank line. - update message to clarify how this is detected - add Cc: stable --- drivers/net/usb/asix_devices.c | 12 +++++++++--- 1 file changed, 9 insertions(+), 3 deletions(-) diff --git a/drivers/net/usb/asix_devices.c b/drivers/net/usb/asix_devices.c index 85bd5d845409..232bbd79a4de 100644 --- a/drivers/net/usb/asix_devices.c +++ b/drivers/net/usb/asix_devices.c @@ -230,7 +230,9 @@ static int ax88172_bind(struct usbnet *dev, struct usb_interface *intf) int i; unsigned long gpio_bits = dev->driver_info->data; - usbnet_get_endpoints(dev,intf); + ret = usbnet_get_endpoints(dev, intf); + if (ret) + goto out; /* Toggle the GPIOs in a manufacturer/model specific way */ for (i = 2; i >= 0; i--) { @@ -848,7 +850,9 @@ static int ax88772_bind(struct usbnet *dev, struct usb_interface *intf) dev->driver_priv = priv; - usbnet_get_endpoints(dev, intf); + ret = usbnet_get_endpoints(dev, intf); + if (ret) + return ret; /* Maybe the boot loader passed the MAC address via device tree */ if (!eth_platform_get_mac_address(&dev->udev->dev, buf)) { @@ -1281,7 +1285,9 @@ static int ax88178_bind(struct usbnet *dev, struct usb_interface *intf) int ret; u8 buf[ETH_ALEN] = {0}; - usbnet_get_endpoints(dev,intf); + ret = usbnet_get_endpoints(dev, intf); + if (ret) + return ret; /* Get the MAC address */ ret = asix_read_cmd(dev, AX_CMD_READ_NODE_ID, 0, 0, ETH_ALEN, buf, 0); -- 2.39.5 (Apple Git-154)

1 week, 4 days

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[PATCH net 0/4] mptcp: various rare sending issues

by Matthieu Baerts (NGI0)

Here are various fixes from Paolo, addressing very occasional issues on the sending side: - Patch 1: drop an optimisation that could lead to timeout in case of race conditions. A fix for up to v5.11. - Patch 2: fix stream corruption under very specific conditions. A fix for up to v5.13. - Patch 3: restore MPTCP-level zero window probe after a recent fix. A fix for up to v5.16. - Patch 4: new MIB counter to track MPTCP-level zero windows probe to help catching issues similar to the one fixed by the previous patch. Signed-off-by: Matthieu Baerts (NGI0) <matttbe(a)kernel.org> --- Paolo Abeni (4): mptcp: drop bogus optimization in __mptcp_check_push() mptcp: fix MSG_PEEK stream corruption mptcp: restore window probe mptcp: zero window probe mib net/mptcp/mib.c | 1 + net/mptcp/mib.h | 1 + net/mptcp/protocol.c | 57 +++++++++++++++++++++++++++++++++------------------- net/mptcp/protocol.h | 2 +- 4 files changed, 39 insertions(+), 22 deletions(-) --- base-commit: 210b35d6a7ea415494ce75490c4b43b4e717d935 change-id: 20251027-net-mptcp-send-timeout-7fc1474fd849 Best regards, -- Matthieu Baerts (NGI0) <matttbe(a)kernel.org>

1 week, 4 days

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[PATCH] drm/ast: Clear preserved bits from register output value

by Thomas Zimmermann

Preserve the I/O register bits in __ast_write8_i_masked() as specified by preserve_mask. Accidentally OR-ing the output value into these will overwrite the register's previous settings. Fixes display output on the AST2300, where the screen can go blank at boot. The driver's original commit 312fec1405dd ("drm: Initial KMS driver for AST (ASpeed Technologies) 2000 series (v2)") already added the broken code. Commit 6f719373b943 ("drm/ast: Blank with VGACR17 sync enable, always clear VGACRB6 sync off") triggered the bug. Signed-off-by: Thomas Zimmermann <tzimmermann(a)suse.de> Reported-by: Peter Schneider <pschneider1968(a)googlemail.com> Closes: https://lore.kernel.org/dri-devel/a40caf8e-58ad-4f9c-af7f-54f6f69c29bb@goog… Tested-by: Peter Schneider <pschneider1968(a)googlemail.com> Fixes: 6f719373b943 ("drm/ast: Blank with VGACR17 sync enable, always clear VGACRB6 sync off") Fixes: 312fec1405dd ("drm: Initial KMS driver for AST (ASpeed Technologies) 2000 series (v2)") Cc: Thomas Zimmermann <tzimmermann(a)suse.de> Cc: Nick Bowler <nbowler(a)draconx.ca> Cc: Douglas Anderson <dianders(a)chromium.org> Cc: Dave Airlie <airlied(a)redhat.com> Cc: Jocelyn Falempe <jfalempe(a)redhat.com> Cc: dri-devel(a)lists.freedesktop.org Cc: <stable(a)vger.kernel.org> # v3.5+ --- drivers/gpu/drm/ast/ast_drv.h | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/ast/ast_drv.h b/drivers/gpu/drm/ast/ast_drv.h index 7be36a358e74..787e38c6c17d 100644 --- a/drivers/gpu/drm/ast/ast_drv.h +++ b/drivers/gpu/drm/ast/ast_drv.h @@ -298,13 +298,13 @@ static inline void __ast_write8_i(void __iomem *addr, u32 reg, u8 index, u8 val) __ast_write8(addr, reg + 1, val); } -static inline void __ast_write8_i_masked(void __iomem *addr, u32 reg, u8 index, u8 read_mask, +static inline void __ast_write8_i_masked(void __iomem *addr, u32 reg, u8 index, u8 preserve_mask, u8 val) { - u8 tmp = __ast_read8_i_masked(addr, reg, index, read_mask); + u8 tmp = __ast_read8_i_masked(addr, reg, index, preserve_mask); - tmp |= val; - __ast_write8_i(addr, reg, index, tmp); + val &= ~preserve_mask; + __ast_write8_i(addr, reg, index, tmp | val); } static inline u32 ast_read32(struct ast_device *ast, u32 reg) -- 2.51.0

1 week, 4 days

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+ kasan-unpoison-vms-addresses-with-a-common-tag.patch added to mm-hotfixes-unstable branch

by Andrew Morton

The patch titled Subject: kasan: unpoison vms[area] addresses with a common tag has been added to the -mm mm-hotfixes-unstable branch. Its filename is kasan-unpoison-vms-addresses-with-a-common-tag.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche… This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Maciej Wieczor-Retman <maciej.wieczor-retman(a)intel.com> Subject: kasan: unpoison vms[area] addresses with a common tag Date: Wed, 29 Oct 2025 19:06:03 +0000 The problem presented here is related to NUMA systems and tag-based KASAN modes - software and hardware ones. It can be explained in the following points: 1. There can be more than one virtual memory chunk. 2. Chunk's base address has a tag. 3. The base address points at the first chunk and thus inherits the tag of the first chunk. 4. The subsequent chunks will be accessed with the tag from the first chunk. 5. Thus, the subsequent chunks need to have their tag set to match that of the first chunk. Unpoison all vms[]->addr memory and pointers with the same tag to resolve the mismatch. Link: https://lkml.kernel.org/r/932121edc75be8e2038d64ecb4853df2e2b258df.17617636… Fixes: 1d96320f8d53 ("kasan, vmalloc: add vmalloc tagging for SW_TAGS") Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman(a)intel.com> Tested-by: Baoquan He <bhe(a)redhat.com> Cc: Alexander Potapenko <glider(a)google.com> Cc: Andrey Konovalov <andreyknvl(a)gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a(a)gmail.com> Cc: Andy Lutomirski <luto(a)kernel.org> Cc: Ard Biesheuvel <ardb(a)kernel.org> Cc: Barry Song <baohua(a)kernel.org> Cc: Bill Wendling <morbo(a)google.com> Cc: Borislav Betkov <bp(a)alien8.de> Cc: Breno Leitao <leitao(a)debian.org> Cc: Brian Gerst <brgerst(a)gmail.com> Cc: Catalin Marinas <catalin.marinas(a)arm.com> Cc: David Hildenbrand <david(a)redhat.com> Cc: Dmitriy Vyukov <dvyukov(a)google.com> Cc: FUJITA Tomonori <fujita.tomonori(a)gmail.com> Cc: Guilherme Giacomo Simoes <trintaeoitogc(a)gmail.com> Cc: "H. Peter Anvin" <hpa(a)zytor.com> Cc: Ingo Molnar <mingo(a)redhat.com> Cc: Jan Kiszka <jan.kiszka(a)siemens.com> Cc: Jeremy Linton <jeremy.linton(a)arm.com> Cc: John Hubbard <jhubbard(a)nvidia.com> Cc: Jonathan Corbet <corbet(a)lwn.net> Cc: Josh Poimboeuf <jpoimboe(a)kernel.org> Cc: Justin Stitt <justinstitt(a)google.com> Cc: Kalesh Singh <kaleshsingh(a)google.com> Cc: Kees Cook <kees(a)kernel.org> Cc: Kefeng Wang <wangkefeng.wang(a)huawei.com> Cc: Kieran Bingham <kbingham(a)kernel.org> Cc: levi.yun <yeoreum.yun(a)arm.com> Cc: Liam Howlett <liam.howlett(a)oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com> Cc: Marco Elver <elver(a)google.com> Cc: Marc Rutland <mark.rutland(a)arm.com> Cc: Marc Zyngier <maz(a)kernel.org> Cc: Mark Brown <broonie(a)kernel.org> Cc: Michal Hocko <mhocko(a)suse.com> Cc: Miguel Ojeda <ojeda(a)kernel.org> Cc: Mike Rapoport <rppt(a)kernel.org> Cc: Mostafa Saleh <smostafa(a)google.com> Cc: Nathan Chancellor <nathan(a)kernel.org> Cc: Pankaj Gupta <pankaj.gupta(a)amd.com> Cc: Pasha Tatashin <pasha.tatashin(a)soleen.com> Cc: Peter Zijlstra <peterz(a)infradead.org> Cc: Samuel Holland <samuel.holland(a)sifive.com> Cc: Sebastian Andrzej Siewior <bigeasy(a)linutronix.de> Cc: Suren Baghdasaryan <surenb(a)google.com> Cc: Thomas Gleinxer <tglx(a)linutronix.de> Cc: Thomas Huth <thuth(a)redhat.com> Cc: "Uladzislau Rezki (Sony)" <urezki(a)gmail.com> Cc: Uros Bizjak <ubizjak(a)gmail.com> Cc: Vincenzo Frascino <vincenzo.frascino(a)arm.com> Cc: Vlastimil Babka <vbabka(a)suse.cz> Cc: Will Deacon <will(a)kernel.org> Cc: Xin Li (Intel) <xin(a)zytor.com> Cc: Zi Yan <ziy(a)nvidia.com> Cc: <stable(a)vger.kernel.org> [6.1+] Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- mm/kasan/tags.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) --- a/mm/kasan/tags.c~kasan-unpoison-vms-addresses-with-a-common-tag +++ a/mm/kasan/tags.c @@ -148,12 +148,20 @@ void __kasan_save_free_info(struct kmem_ save_stack_info(cache, object, 0, true); } +/* + * A tag mismatch happens when calculating per-cpu chunk addresses, because + * they all inherit the tag from vms[0]->addr, even when nr_vms is bigger + * than 1. This is a problem because all the vms[]->addr come from separate + * allocations and have different tags so while the calculated address is + * correct the tag isn't. + */ void __kasan_unpoison_vmap_areas(struct vm_struct **vms, int nr_vms) { int area; for (area = 0 ; area < nr_vms ; area++) { kasan_poison(vms[area]->addr, vms[area]->size, - arch_kasan_get_tag(vms[area]->addr), false); + arch_kasan_get_tag(vms[0]->addr), false); + arch_kasan_set_tag(vms[area]->addr, arch_kasan_get_tag(vms[0]->addr)); } } _ Patches currently in -mm which might be from maciej.wieczor-retman(a)intel.com are kasan-unpoison-pcpu-chunks-with-base-address-tag.patch kasan-unpoison-vms-addresses-with-a-common-tag.patch

1 week, 4 days

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+ kasan-unpoison-pcpu-chunks-with-base-address-tag.patch added to mm-hotfixes-unstable branch

by Andrew Morton

The patch titled Subject: kasan: unpoison pcpu chunks with base address tag has been added to the -mm mm-hotfixes-unstable branch. Its filename is kasan-unpoison-pcpu-chunks-with-base-address-tag.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patche… This patch will later appear in the mm-hotfixes-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Maciej Wieczor-Retman <maciej.wieczor-retman(a)intel.com> Subject: kasan: unpoison pcpu chunks with base address tag Date: Wed, 29 Oct 2025 19:05:49 +0000 The problem presented here is related to NUMA systems and tag-based KASAN modes - software and hardware ones. It can be explained in the following points: 1. There can be more than one virtual memory chunk. 2. Chunk's base address has a tag. 3. The base address points at the first chunk and thus inherits the tag of the first chunk. 4. The subsequent chunks will be accessed with the tag from the first chunk. 5. Thus, the subsequent chunks need to have their tag set to match that of the first chunk. Refactor code by moving it into a helper in preparation for the actual fix. Link: https://lkml.kernel.org/r/fbce40a59b0a22a5735cb6e9b95c5a45a34b23cb.17617636… Fixes: 1d96320f8d53 ("kasan, vmalloc: add vmalloc tagging for SW_TAGS") Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman(a)intel.com> Tested-by: Baoquan He <bhe(a)redhat.com> Cc: Alexander Potapenko <glider(a)google.com> Cc: Andrey Konovalov <andreyknvl(a)gmail.com> Cc: Andrey Ryabinin <ryabinin.a.a(a)gmail.com> Cc: Andy Lutomirski <luto(a)kernel.org> Cc: Ard Biesheuvel <ardb(a)kernel.org> Cc: Barry Song <baohua(a)kernel.org> Cc: Bill Wendling <morbo(a)google.com> Cc: Borislav Betkov <bp(a)alien8.de> Cc: Breno Leitao <leitao(a)debian.org> Cc: Brian Gerst <brgerst(a)gmail.com> Cc: Catalin Marinas <catalin.marinas(a)arm.com> Cc: David Hildenbrand <david(a)redhat.com> Cc: Dmitriy Vyukov <dvyukov(a)google.com> Cc: FUJITA Tomonori <fujita.tomonori(a)gmail.com> Cc: Guilherme Giacomo Simoes <trintaeoitogc(a)gmail.com> Cc: "H. Peter Anvin" <hpa(a)zytor.com> Cc: Ingo Molnar <mingo(a)redhat.com> Cc: Jan Kiszka <jan.kiszka(a)siemens.com> Cc: Jeremy Linton <jeremy.linton(a)arm.com> Cc: John Hubbard <jhubbard(a)nvidia.com> Cc: Jonathan Corbet <corbet(a)lwn.net> Cc: Josh Poimboeuf <jpoimboe(a)kernel.org> Cc: Justin Stitt <justinstitt(a)google.com> Cc: Kalesh Singh <kaleshsingh(a)google.com> Cc: Kees Cook <kees(a)kernel.org> Cc: Kefeng Wang <wangkefeng.wang(a)huawei.com> Cc: Kieran Bingham <kbingham(a)kernel.org> Cc: levi.yun <yeoreum.yun(a)arm.com> Cc: Liam Howlett <liam.howlett(a)oracle.com> Cc: Lorenzo Stoakes <lorenzo.stoakes(a)oracle.com> Cc: Marco Elver <elver(a)google.com> Cc: Marc Rutland <mark.rutland(a)arm.com> Cc: Marc Zyngier <maz(a)kernel.org> Cc: Mark Brown <broonie(a)kernel.org> Cc: Michal Hocko <mhocko(a)suse.com> Cc: Miguel Ojeda <ojeda(a)kernel.org> Cc: Mike Rapoport <rppt(a)kernel.org> Cc: Mostafa Saleh <smostafa(a)google.com> Cc: Nathan Chancellor <nathan(a)kernel.org> Cc: Pankaj Gupta <pankaj.gupta(a)amd.com> Cc: Pasha Tatashin <pasha.tatashin(a)soleen.com> Cc: Peter Zijlstra <peterz(a)infradead.org> Cc: Samuel Holland <samuel.holland(a)sifive.com> Cc: Sebastian Andrzej Siewior <bigeasy(a)linutronix.de> Cc: Suren Baghdasaryan <surenb(a)google.com> Cc: Thomas Gleinxer <tglx(a)linutronix.de> Cc: Thomas Huth <thuth(a)redhat.com> Cc: "Uladzislau Rezki (Sony)" <urezki(a)gmail.com> Cc: Uros Bizjak <ubizjak(a)gmail.com> Cc: Vincenzo Frascino <vincenzo.frascino(a)arm.com> Cc: Vlastimil Babka <vbabka(a)suse.cz> Cc: Will Deacon <will(a)kernel.org> Cc: Xin Li (Intel) <xin(a)zytor.com> Cc: Zi Yan <ziy(a)nvidia.com> Cc: <stable(a)vger.kernel.org> [6.1+] Signed-off-by: Andrew Morton <akpm(a)linux-foundation.org> --- include/linux/kasan.h | 10 ++++++++++ mm/kasan/tags.c | 11 +++++++++++ mm/vmalloc.c | 4 +--- 3 files changed, 22 insertions(+), 3 deletions(-) --- a/include/linux/kasan.h~kasan-unpoison-pcpu-chunks-with-base-address-tag +++ a/include/linux/kasan.h @@ -614,6 +614,13 @@ static __always_inline void kasan_poison __kasan_poison_vmalloc(start, size); } +void __kasan_unpoison_vmap_areas(struct vm_struct **vms, int nr_vms); +static __always_inline void kasan_unpoison_vmap_areas(struct vm_struct **vms, int nr_vms) +{ + if (kasan_enabled()) + __kasan_unpoison_vmap_areas(vms, nr_vms); +} + #else /* CONFIG_KASAN_VMALLOC */ static inline void kasan_populate_early_vm_area_shadow(void *start, @@ -638,6 +645,9 @@ static inline void *kasan_unpoison_vmall static inline void kasan_poison_vmalloc(const void *start, unsigned long size) { } +static inline void kasan_unpoison_vmap_areas(struct vm_struct **vms, int nr_vms) +{ } + #endif /* CONFIG_KASAN_VMALLOC */ #if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \ --- a/mm/kasan/tags.c~kasan-unpoison-pcpu-chunks-with-base-address-tag +++ a/mm/kasan/tags.c @@ -18,6 +18,7 @@ #include <linux/static_key.h> #include <linux/string.h> #include <linux/types.h> +#include <linux/vmalloc.h> #include "kasan.h" #include "../slab.h" @@ -146,3 +147,13 @@ void __kasan_save_free_info(struct kmem_ { save_stack_info(cache, object, 0, true); } + +void __kasan_unpoison_vmap_areas(struct vm_struct **vms, int nr_vms) +{ + int area; + + for (area = 0 ; area < nr_vms ; area++) { + kasan_poison(vms[area]->addr, vms[area]->size, + arch_kasan_get_tag(vms[area]->addr), false); + } +} --- a/mm/vmalloc.c~kasan-unpoison-pcpu-chunks-with-base-address-tag +++ a/mm/vmalloc.c @@ -4870,9 +4870,7 @@ retry: * With hardware tag-based KASAN, marking is skipped for * non-VM_ALLOC mappings, see __kasan_unpoison_vmalloc(). */ - for (area = 0; area < nr_vms; area++) - vms[area]->addr = kasan_unpoison_vmalloc(vms[area]->addr, - vms[area]->size, KASAN_VMALLOC_PROT_NORMAL); + kasan_unpoison_vmap_areas(vms, nr_vms); kfree(vas); return vms; _ Patches currently in -mm which might be from maciej.wieczor-retman(a)intel.com are kasan-unpoison-pcpu-chunks-with-base-address-tag.patch kasan-unpoison-vms-addresses-with-a-common-tag.patch

1 week, 4 days

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[PATCH v6 02/18] kasan: Unpoison vms[area] addresses with a common tag

by Maciej Wieczor-Retman

From: Maciej Wieczor-Retman <maciej.wieczor-retman(a)intel.com> The problem presented here is related to NUMA systems and tag-based KASAN modes - software and hardware ones. It can be explained in the following points: 1. There can be more than one virtual memory chunk. 2. Chunk's base address has a tag. 3. The base address points at the first chunk and thus inherits the tag of the first chunk. 4. The subsequent chunks will be accessed with the tag from the first chunk. 5. Thus, the subsequent chunks need to have their tag set to match that of the first chunk. Unpoison all vms[]->addr memory and pointers with the same tag to resolve the mismatch. Fixes: 1d96320f8d53 ("kasan, vmalloc: add vmalloc tagging for SW_TAGS") Cc: <stable(a)vger.kernel.org> # 6.1+ Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman(a)intel.com> Tested-by: Baoquan He <bhe(a)redhat.com> --- Changelog v6: - Add Baoquan's tested-by tag. - Move patch to the beginning of the series as it is a fix. - Add fixes tag. mm/kasan/tags.c | 10 +++++++++- 1 file changed, 9 insertions(+), 1 deletion(-) diff --git a/mm/kasan/tags.c b/mm/kasan/tags.c index ecc17c7c675a..c6b40cbffae3 100644 --- a/mm/kasan/tags.c +++ b/mm/kasan/tags.c @@ -148,12 +148,20 @@ void __kasan_save_free_info(struct kmem_cache *cache, void *object) save_stack_info(cache, object, 0, true); } +/* + * A tag mismatch happens when calculating per-cpu chunk addresses, because + * they all inherit the tag from vms[0]->addr, even when nr_vms is bigger + * than 1. This is a problem because all the vms[]->addr come from separate + * allocations and have different tags so while the calculated address is + * correct the tag isn't. + */ void __kasan_unpoison_vmap_areas(struct vm_struct **vms, int nr_vms) { int area; for (area = 0 ; area < nr_vms ; area++) { kasan_poison(vms[area]->addr, vms[area]->size, - arch_kasan_get_tag(vms[area]->addr), false); + arch_kasan_get_tag(vms[0]->addr), false); + arch_kasan_set_tag(vms[area]->addr, arch_kasan_get_tag(vms[0]->addr)); } } -- 2.51.0

1 week, 4 days

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[PATCH v6 01/18] kasan: Unpoison pcpu chunks with base address tag

by Maciej Wieczor-Retman

From: Maciej Wieczor-Retman <maciej.wieczor-retman(a)intel.com> The problem presented here is related to NUMA systems and tag-based KASAN modes - software and hardware ones. It can be explained in the following points: 1. There can be more than one virtual memory chunk. 2. Chunk's base address has a tag. 3. The base address points at the first chunk and thus inherits the tag of the first chunk. 4. The subsequent chunks will be accessed with the tag from the first chunk. 5. Thus, the subsequent chunks need to have their tag set to match that of the first chunk. Refactor code by moving it into a helper in preparation for the actual fix. Fixes: 1d96320f8d53 ("kasan, vmalloc: add vmalloc tagging for SW_TAGS") Cc: <stable(a)vger.kernel.org> # 6.1+ Signed-off-by: Maciej Wieczor-Retman <maciej.wieczor-retman(a)intel.com> Tested-by: Baoquan He <bhe(a)redhat.com> --- Changelog v6: - Add Baoquan's tested-by tag. - Move patch to the beginning of the series as it is a fix. - Move the refactored code to tags.c because both software and hardware modes compile it. - Add fixes tag. Changelog v4: - Redo the patch message numbered list. - Do the refactoring in this patch and move additions to the next new one. Changelog v3: - Remove last version of this patch that just resets the tag on base_addr and add this patch that unpoisons all areas with the same tag instead. include/linux/kasan.h | 10 ++++++++++ mm/kasan/tags.c | 11 +++++++++++ mm/vmalloc.c | 4 +--- 3 files changed, 22 insertions(+), 3 deletions(-) diff --git a/include/linux/kasan.h b/include/linux/kasan.h index d12e1a5f5a9a..b00849ea8ffd 100644 --- a/include/linux/kasan.h +++ b/include/linux/kasan.h @@ -614,6 +614,13 @@ static __always_inline void kasan_poison_vmalloc(const void *start, __kasan_poison_vmalloc(start, size); } +void __kasan_unpoison_vmap_areas(struct vm_struct **vms, int nr_vms); +static __always_inline void kasan_unpoison_vmap_areas(struct vm_struct **vms, int nr_vms) +{ + if (kasan_enabled()) + __kasan_unpoison_vmap_areas(vms, nr_vms); +} + #else /* CONFIG_KASAN_VMALLOC */ static inline void kasan_populate_early_vm_area_shadow(void *start, @@ -638,6 +645,9 @@ static inline void *kasan_unpoison_vmalloc(const void *start, static inline void kasan_poison_vmalloc(const void *start, unsigned long size) { } +static inline void kasan_unpoison_vmap_areas(struct vm_struct **vms, int nr_vms) +{ } + #endif /* CONFIG_KASAN_VMALLOC */ #if (defined(CONFIG_KASAN_GENERIC) || defined(CONFIG_KASAN_SW_TAGS)) && \ diff --git a/mm/kasan/tags.c b/mm/kasan/tags.c index b9f31293622b..ecc17c7c675a 100644 --- a/mm/kasan/tags.c +++ b/mm/kasan/tags.c @@ -18,6 +18,7 @@ #include <linux/static_key.h> #include <linux/string.h> #include <linux/types.h> +#include <linux/vmalloc.h> #include "kasan.h" #include "../slab.h" @@ -146,3 +147,13 @@ void __kasan_save_free_info(struct kmem_cache *cache, void *object) { save_stack_info(cache, object, 0, true); } + +void __kasan_unpoison_vmap_areas(struct vm_struct **vms, int nr_vms) +{ + int area; + + for (area = 0 ; area < nr_vms ; area++) { + kasan_poison(vms[area]->addr, vms[area]->size, + arch_kasan_get_tag(vms[area]->addr), false); + } +} diff --git a/mm/vmalloc.c b/mm/vmalloc.c index 798b2ed21e46..934c8bfbcebf 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -4870,9 +4870,7 @@ struct vm_struct **pcpu_get_vm_areas(const unsigned long *offsets, * With hardware tag-based KASAN, marking is skipped for * non-VM_ALLOC mappings, see __kasan_unpoison_vmalloc(). */ - for (area = 0; area < nr_vms; area++) - vms[area]->addr = kasan_unpoison_vmalloc(vms[area]->addr, - vms[area]->size, KASAN_VMALLOC_PROT_NORMAL); + kasan_unpoison_vmap_areas(vms, nr_vms); kfree(vas); return vms; -- 2.51.0

1 week, 4 days

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Bug: Performance regression in 1013af4f585f: mm/hugetlb: fix huge_pmd_unshare() vs GUP-fast race

by Uschakow, Stanislav

Hello. We have observed a huge latency increase using `fork()` after ingesting the CVE-2025-38085 fix which leads to the commit `1013af4f585f: mm/hugetlb: fix huge_pmd_unshare() vs GUP-fast race`. On large machines with 1.5TB of memory with 196 cores, we identified mmapping of 1.2TB of shared memory and forking itself dozens or hundreds of times we see a increase of execution times of a factor of 4. The reproducer is at the end of the email. Comparing the a kernel without this patch with a kernel with this patch applied when spawning 1000 children we see those execution times: Patched kernel: $ time make stress ... real 0m11.275s user 0m0.177s sys 0m23.905s Original kernel : $ time make stress ...real 0m2.475s user 0m1.398s sys 0m2.501s The patch in question: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… My observation/assumption is: each child touches 100 random pages and despawns on each despawn `huge_pmd_unshare()` is called each call to `huge_pmd_unshare()` syncrhonizes all threads using `tlb_remove_table_sync_one()` leading to the regression I'm happy to provide more information. Thank you Stanislav Uschakow === Reproducer === Setup: #!/bin/bash echo "Setting up hugepages for reproduction..." # hugepages (1.2TB / 2MB = 614400 pages) REQUIRED_PAGES=614400 # Check current hugepage allocation CURRENT_PAGES=$(cat /proc/sys/vm/nr_hugepages) echo "Current hugepages: $CURRENT_PAGES" if [ "$CURRENT_PAGES" -lt "$REQUIRED_PAGES" ]; then echo "Allocating $REQUIRED_PAGES hugepages..." echo $REQUIRED_PAGES | sudo tee /proc/sys/vm/nr_hugepages ALLOCATED=$(cat /proc/sys/vm/nr_hugepages) echo "Allocated hugepages: $ALLOCATED" if [ "$ALLOCATED" -lt "$REQUIRED_PAGES" ]; then echo "Warning: Could not allocate all required hugepages" echo "Available: $ALLOCATED, Required: $REQUIRED_PAGES" fi fi echo never | sudo tee /sys/kernel/mm/transparent_hugepage/enabled echo -e "\nHugepage information:" cat /proc/meminfo | grep -i huge echo -e "\nSetup complete. You can now run the reproduction test." Makefile: CXX = gcc CXXFLAGS = -O2 -Wall TARGET = hugepage_repro SOURCE = hugepage_repro.c $(TARGET): $(SOURCE) $(CXX) $(CXXFLAGS) -o $(TARGET) $(SOURCE) clean: rm -f $(TARGET) setup: chmod +x setup_hugepages.sh ./setup_hugepages.sh test: $(TARGET) ./$(TARGET) 20 3 stress: $(TARGET) ./$(TARGET) 1000 1 .PHONY: clean setup test stress hugepage_repro.c: #include <sys/mman.h> #include <sys/wait.h> #include <unistd.h> #include <stdlib.h> #include <string.h> #include <time.h> #include <stdio.h> #define HUGEPAGE_SIZE (2 * 1024 * 1024) // 2MB #define TOTAL_SIZE (1200ULL * 1024 * 1024 * 1024) // 1.2TB #define NUM_HUGEPAGES (TOTAL_SIZE / HUGEPAGE_SIZE) void* create_hugepage_mapping() { void* addr = mmap(NULL, TOTAL_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS | MAP_HUGETLB, -1, 0); if (addr == MAP_FAILED) { perror("mmap hugepages failed"); exit(1); } return addr; } void touch_random_pages(void* addr, int num_touches) { char* base = (char*)addr; for (int i = 0; i < num_touches; ++i) { size_t offset = (rand() % NUM_HUGEPAGES) * HUGEPAGE_SIZE; volatile char val = base[offset]; (void)val; } } void child_process(void* shared_mem, int child_id) { struct timespec start, end; clock_gettime(CLOCK_MONOTONIC, &start); touch_random_pages(shared_mem, 100); clock_gettime(CLOCK_MONOTONIC, &end); long duration = (end.tv_sec - start.tv_sec) * 1000000 + (end.tv_nsec - start.tv_nsec) / 1000; printf("Child %d completed in %ld μs\n", child_id, duration); } int main(int argc, char* argv[]) { int num_processes = argc > 1 ? atoi(argv[1]) : 50; int iterations = argc > 2 ? atoi(argv[2]) : 5; printf("Creating %lluGB hugepage mapping...\n", TOTAL_SIZE / (1024*1024*1024)); void* shared_mem = create_hugepage_mapping(); for (int iter = 0; iter < iterations; ++iter) { printf("\nIteration %d: Forking %d processes\n", iter + 1, num_processes); pid_t children[num_processes]; struct timespec iter_start, iter_end; clock_gettime(CLOCK_MONOTONIC, &iter_start); for (int i = 0; i < num_processes; ++i) { pid_t pid = fork(); if (pid == 0) { child_process(shared_mem, i); exit(0); } else if (pid > 0) { children[i] = pid; } } for (int i = 0; i < num_processes; ++i) { waitpid(children[i], NULL, 0); } clock_gettime(CLOCK_MONOTONIC, &iter_end); long iter_duration = (iter_end.tv_sec - iter_start.tv_sec) * 1000 + (iter_end.tv_nsec - iter_start.tv_nsec) / 1000000; printf("Iteration completed in %ld ms\n", iter_duration); } munmap(shared_mem, TOTAL_SIZE); return 0; } Amazon Web Services Development Center Germany GmbH Tamara-Danz-Str. 13 10243 Berlin Geschaeftsfuehrung: Christian Schlaeger, Jonathan Weiss Eingetragen am Amtsgericht Charlottenburg unter HRB 257764 B Sitz: Berlin Ust-ID: DE 365 538 597

1 week, 4 days

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[PATCH 06/25] media: i2c: ov01a10: Fix test-pattern disabling

by Hans de Goede

When the test-pattern control gets set to 0 (Disabled) 0 should be written to the test-pattern register, rather then doing nothing. Fixes: 0827b58dabff ("media: i2c: add ov01a10 image sensor driver") Cc: stable(a)vger.kernel.org Signed-off-by: Hans de Goede <hansg(a)kernel.org> --- drivers/media/i2c/ov01a10.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/drivers/media/i2c/ov01a10.c b/drivers/media/i2c/ov01a10.c index 0405ec7c75fd..733e5bf0180c 100644 --- a/drivers/media/i2c/ov01a10.c +++ b/drivers/media/i2c/ov01a10.c @@ -406,10 +406,8 @@ static int ov01a10_update_digital_gain(struct ov01a10 *ov01a10, u32 d_gain) static int ov01a10_test_pattern(struct ov01a10 *ov01a10, u32 pattern) { - if (!pattern) - return 0; - - pattern = (pattern - 1) | OV01A10_TEST_PATTERN_ENABLE; + if (pattern) + pattern = (pattern - 1) | OV01A10_TEST_PATTERN_ENABLE; return ov01a10_write_reg(ov01a10, OV01A10_REG_TEST_PATTERN, 1, pattern); } -- 2.51.0

1 week, 4 days

3
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