March 2024 - Kernel - mailweb.openeuler.org

[PATCH OLK-5.10] mm,ima,kexec,of: use memblock_free_late from ima_free_kexec_buffer
by GUO Zihua 05 Mar '24

05 Mar '24

From: Rik van Riel <riel(a)surriel.com> mainline inclusion from mainline-v5.13-rc1 commit f0362a253606e2031f8d61c74195d4d6556e12a4 category: bugfix bugzilla: https://gitee.com/openeuler/kernel/issues/I960AB CVE: NA Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?… -------------------------------- The code calling ima_free_kexec_buffer runs long after the memblock allocator has already been torn down, potentially resulting in a use after free in memblock_isolate_range. With KASAN or KFENCE, this use after free will result in a BUG from the idle task, and a subsequent kernel panic. Switch ima_free_kexec_buffer over to memblock_free_late to avoid that issue. Fixes: fee3ff99bc67 ("powerpc: Move arch independent ima kexec functions to drivers/of/kexec.c") Cc: stable(a)kernel.org Signed-off-by: Rik van Riel <riel(a)surriel.com> Suggested-by: Mike Rappoport <rppt(a)kernel.org> Link: https://lore.kernel.org/r/20230817135759.0888e5ef@imladris.surriel.com Signed-off-by: Rob Herring <robh(a)kernel.org> Conflicts: drivers/of/kexec.c Signed-off-by: GUO Zihua <guozihua(a)huawei.com> --- drivers/of/kexec.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/of/kexec.c b/drivers/of/kexec.c index d8231c34e873..2d1fd5587123 100644 --- a/drivers/of/kexec.c +++ b/drivers/of/kexec.c @@ -178,7 +178,8 @@ int ima_free_kexec_buffer(void) if (ret) return ret; - return memblock_free(addr, size); + memblock_free_late(addr, size); + return 0; } -- 2.34.1

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[PATCH openEuler-1.0-LTS 0/1] powerpc/64s: Fix pte update for kernel memory on radix
by Huang Xiaojia 05 Mar '24

05 Mar '24

Jordan Niethe (1): powerpc/64s: Fix pte update for kernel memory on radix arch/powerpc/include/asm/book3s/64/radix.h | 6 ++++-- arch/powerpc/mm/pgtable-radix.c | 4 ++-- 2 files changed, 6 insertions(+), 4 deletions(-) -- 2.34.1

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[PATCH openEuler-1.0-LTS] NFC: st21nfca: Fix memory leak in device probe and remove
by Dong Chenchen 05 Mar '24

05 Mar '24

From: Wei Yongjun <weiyongjun1(a)huawei.com> stable inclusion from stable-v4.19.223 commit a1e0080a35a16ce3808f7040fe0c3a8fdb052349 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I947OW CVE: CVE-2021-46924 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 1b9dadba502234eea7244879b8d5d126bfaf9f0c ] 'phy->pending_skb' is alloced when device probe, but forgot to free in the error handling path and remove path, this cause memory leak as follows: unreferenced object 0xffff88800bc06800 (size 512): comm "8", pid 11775, jiffies 4295159829 (age 9.032s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ backtrace: [<00000000d66c09ce>] __kmalloc_node_track_caller+0x1ed/0x450 [<00000000c93382b3>] kmalloc_reserve+0x37/0xd0 [<000000005fea522c>] __alloc_skb+0x124/0x380 [<0000000019f29f9a>] st21nfca_hci_i2c_probe+0x170/0x8f2 Fix it by freeing 'pending_skb' in error and remove. Fixes: 68957303f44a ("NFC: ST21NFCA: Add driver for STMicroelectronics ST21NFCA NFC Chip") Reported-by: Hulk Robot <hulkci(a)huawei.com> Signed-off-by: Wei Yongjun <weiyongjun1(a)huawei.com> Signed-off-by: David S. Miller <davem(a)davemloft.net> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Dong Chenchen <dongchenchen2(a)huawei.com> --- drivers/nfc/st21nfca/i2c.c | 29 ++++++++++++++++++++--------- 1 file changed, 20 insertions(+), 9 deletions(-) diff --git a/drivers/nfc/st21nfca/i2c.c b/drivers/nfc/st21nfca/i2c.c index 1b347096422f..ebea3b4dd8e1 100644 --- a/drivers/nfc/st21nfca/i2c.c +++ b/drivers/nfc/st21nfca/i2c.c @@ -544,7 +544,8 @@ static int st21nfca_hci_i2c_probe(struct i2c_client *client, phy->gpiod_ena = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW); if (IS_ERR(phy->gpiod_ena)) { nfc_err(dev, "Unable to get ENABLE GPIO\n"); - return PTR_ERR(phy->gpiod_ena); + r = PTR_ERR(phy->gpiod_ena); + goto out_free; } phy->se_status.is_ese_present = @@ -555,7 +556,7 @@ static int st21nfca_hci_i2c_probe(struct i2c_client *client, r = st21nfca_hci_platform_init(phy); if (r < 0) { nfc_err(&client->dev, "Unable to reboot st21nfca\n"); - return r; + goto out_free; } r = devm_request_threaded_irq(&client->dev, client->irq, NULL, @@ -564,15 +565,23 @@ static int st21nfca_hci_i2c_probe(struct i2c_client *client, ST21NFCA_HCI_DRIVER_NAME, phy); if (r < 0) { nfc_err(&client->dev, "Unable to register IRQ handler\n"); - return r; + goto out_free; } - return st21nfca_hci_probe(phy, &i2c_phy_ops, LLC_SHDLC_NAME, - ST21NFCA_FRAME_HEADROOM, - ST21NFCA_FRAME_TAILROOM, - ST21NFCA_HCI_LLC_MAX_PAYLOAD, - &phy->hdev, - &phy->se_status); + r = st21nfca_hci_probe(phy, &i2c_phy_ops, LLC_SHDLC_NAME, + ST21NFCA_FRAME_HEADROOM, + ST21NFCA_FRAME_TAILROOM, + ST21NFCA_HCI_LLC_MAX_PAYLOAD, + &phy->hdev, + &phy->se_status); + if (r) + goto out_free; + + return 0; + +out_free: + kfree_skb(phy->pending_skb); + return r; } static int st21nfca_hci_i2c_remove(struct i2c_client *client) @@ -585,6 +594,8 @@ static int st21nfca_hci_i2c_remove(struct i2c_client *client) if (phy->powered) st21nfca_hci_i2c_disable(phy); + if (phy->pending_skb) + kfree_skb(phy->pending_skb); return 0; } -- 2.25.1

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[PATCH openEuler-1.0-LTS] ieee802154: ca8210: Fix a potential UAF in ca8210_probe
by Yu Liao 05 Mar '24

05 Mar '24

From: Dinghao Liu <dinghao.liu(a)zju.edu.cn> stable inclusion from stable-v4.19.297 commit cdb46be93c1f7bbf2c4649e9fc5fb147cfb5245d category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I95ASM CVE: CVE-2023-52510 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit f990874b1c98fe8e57ee9385669f501822979258 ] If of_clk_add_provider() fails in ca8210_register_ext_clock(), it calls clk_unregister() to release priv->clk and returns an error. However, the caller ca8210_probe() then calls ca8210_remove(), where priv->clk is freed again in ca8210_unregister_ext_clock(). In this case, a use-after-free may happen in the second time we call clk_unregister(). Fix this by removing the first clk_unregister(). Also, priv->clk could be an error code on failure of clk_register_fixed_rate(). Use IS_ERR_OR_NULL to catch this case in ca8210_unregister_ext_clock(). Fixes: ded845a781a5 ("ieee802154: Add CA8210 IEEE 802.15.4 device driver") Signed-off-by: Dinghao Liu <dinghao.liu(a)zju.edu.cn> Message-ID: <20231007033049.22353-1-dinghao.liu(a)zju.edu.cn> Signed-off-by: Stefan Schmidt <stefan(a)datenfreihafen.org> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Yu Liao <liaoyu15(a)huawei.com> --- drivers/net/ieee802154/ca8210.c | 17 +++-------------- 1 file changed, 3 insertions(+), 14 deletions(-) diff --git a/drivers/net/ieee802154/ca8210.c b/drivers/net/ieee802154/ca8210.c index 38a41651e451..324ce317b864 100644 --- a/drivers/net/ieee802154/ca8210.c +++ b/drivers/net/ieee802154/ca8210.c @@ -2779,7 +2779,6 @@ static int ca8210_register_ext_clock(struct spi_device *spi) struct device_node *np = spi->dev.of_node; struct ca8210_priv *priv = spi_get_drvdata(spi); struct ca8210_platform_data *pdata = spi->dev.platform_data; - int ret = 0; if (!np) return -EFAULT; @@ -2796,18 +2795,8 @@ static int ca8210_register_ext_clock(struct spi_device *spi) dev_crit(&spi->dev, "Failed to register external clk\n"); return PTR_ERR(priv->clk); } - ret = of_clk_add_provider(np, of_clk_src_simple_get, priv->clk); - if (ret) { - clk_unregister(priv->clk); - dev_crit( - &spi->dev, - "Failed to register external clock as clock provider\n" - ); - } else { - dev_info(&spi->dev, "External clock set as clock provider\n"); - } - return ret; + return of_clk_add_provider(np, of_clk_src_simple_get, priv->clk); } /** @@ -2819,8 +2808,8 @@ static void ca8210_unregister_ext_clock(struct spi_device *spi) { struct ca8210_priv *priv = spi_get_drvdata(spi); - if (!priv->clk) - return + if (IS_ERR_OR_NULL(priv->clk)) + return; of_clk_del_provider(spi->dev.of_node); clk_unregister(priv->clk); -- 2.25.1

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[PATCH openEuler-1.0-LTS] perf/x86/lbr: Filter vsyscall addresses
by Luo Gengkun 05 Mar '24

05 Mar '24

From: JP Kobryn <inwardvessel(a)gmail.com> mainline inclusion from mainline-v6.6-rc6 commit e53899771a02f798d436655efbd9d4b46c0f9265 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I94P3R CVE: CVE-2023-52476 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- We found that a panic can occur when a vsyscall is made while LBR sampling is active. If the vsyscall is interrupted (NMI) for perf sampling, this call sequence can occur (most recent at top): __insn_get_emulate_prefix() insn_get_emulate_prefix() insn_get_prefixes() insn_get_opcode() decode_branch_type() get_branch_type() intel_pmu_lbr_filter() intel_pmu_handle_irq() perf_event_nmi_handler() Within __insn_get_emulate_prefix() at frame 0, a macro is called: peek_nbyte_next(insn_byte_t, insn, i) Within this macro, this dereference occurs: (insn)->next_byte Inspecting registers at this point, the value of the next_byte field is the address of the vsyscall made, for example the location of the vsyscall version of gettimeofday() at 0xffffffffff600000. The access to an address in the vsyscall region will trigger an oops due to an unhandled page fault. To fix the bug, filtering for vsyscalls can be done when determining the branch type. This patch will return a "none" branch if a kernel address if found to lie in the vsyscall region. Suggested-by: Alexei Starovoitov <ast(a)kernel.org> Signed-off-by: JP Kobryn <inwardvessel(a)gmail.com> Signed-off-by: Ingo Molnar <mingo(a)kernel.org> Cc: stable(a)vger.kernel.org Conflicts: arch/x86/events/utils.c Signed-off-by: Luo Gengkun <luogengkun2(a)huawei.com> --- arch/x86/events/intel/lbr.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c index a3dc3b5bc78d..1fb1ede03c40 100644 --- a/arch/x86/events/intel/lbr.c +++ b/arch/x86/events/intel/lbr.c @@ -5,6 +5,7 @@ #include <asm/perf_event.h> #include <asm/msr.h> #include <asm/insn.h> +#include <linux/mm.h> #include "../perf_event.h" @@ -894,9 +895,9 @@ static int branch_type(unsigned long from, unsigned long to, int abort) * The LBR logs any address in the IP, even if the IP just * faulted. This means userspace can control the from address. * Ensure we don't blindy read any address by validating it is - * a known text address. + * a known text address and not a vsyscall address. */ - if (kernel_text_address(from)) { + if (kernel_text_address(from) && !in_gate_area_no_mm(from)) { addr = (void *)from; /* * Assume we can get the maximum possible size -- 2.34.1

2 1

[PATCH OLK-5.10 0/1] sched: migtate user interface from smart grid to sched bpf
by Liao Chen 05 Mar '24

05 Mar '24

Migtating user interface from smart grid to sched bpf, which allows users to set SCHED_GRID_QOS_TASK_LEVEL through: /proc/${pid}/task/${pid}/tag interface. Although arbitrary integer value could be assigned to , currnetly we clamp the value of SCHED_GRID_QOS_TASK_LEVEL to 0-7, which maintains consistency. Liao Chen (1): sched: migtate user interface from smart grid to sched bpf fs/proc/base.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) -- 2.34.1

2 2

[PATCH openEuler-22.03-LTS] Input: powermate - fix use-after-free in powermate_config_complete
by Xiang Yang 05 Mar '24

05 Mar '24

From: Javier Carrasco <javier.carrasco.cruz(a)gmail.com> stable inclusion from stable-v5.10.199 commit cd2fbfd8b922b7fdd50732e47d797754ab59cb06 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I94PA7 CVE: CVE-2023-52475 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- commit 5c15c60e7be615f05a45cd905093a54b11f461bc upstream. syzbot has found a use-after-free bug [1] in the powermate driver. This happens when the device is disconnected, which leads to a memory free from the powermate_device struct. When an asynchronous control message completes after the kfree and its callback is invoked, the lock does not exist anymore and hence the bug. Use usb_kill_urb() on pm->config to cancel any in-progress requests upon device disconnection. [1] https://syzkaller.appspot.com/bug?extid=0434ac83f907a1dbdd1e Signed-off-by: Javier Carrasco <javier.carrasco.cruz(a)gmail.com> Reported-by: syzbot+0434ac83f907a1dbdd1e(a)syzkaller.appspotmail.com Link: https://lore.kernel.org/r/20230916-topic-powermate_use_after_free-v3-1-6441… Signed-off-by: Dmitry Torokhov <dmitry.torokhov(a)gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh(a)linuxfoundation.org> Signed-off-by: Xiang Yang <xiangyang3(a)huawei.com> --- drivers/input/misc/powermate.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/input/misc/powermate.c b/drivers/input/misc/powermate.c index c4e0e1886061..6b1b95d58e6b 100644 --- a/drivers/input/misc/powermate.c +++ b/drivers/input/misc/powermate.c @@ -425,6 +425,7 @@ static void powermate_disconnect(struct usb_interface *intf) pm->requires_update = 0; usb_kill_urb(pm->irq); input_unregister_device(pm->input); + usb_kill_urb(pm->config); usb_free_urb(pm->irq); usb_free_urb(pm->config); powermate_free_buffers(interface_to_usbdev(intf), pm); -- 2.34.1

2 1

[PATCH OLK-6.6] apparmor: avoid crash when parsed profile name is empty
by Xiang Yang 05 Mar '24

05 Mar '24

From: Fedor Pchelkin <pchelkin(a)ispras.ru> stable inclusion from stable-v6.6.14 commit 5c0392fdafb0a2321311900be83ffa572bef8203 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I932W7 CVE: CVE-2023-52443 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- [ Upstream commit 55a8210c9e7d21ff2644809699765796d4bfb200 ] When processing a packed profile in unpack_profile() described like "profile :ns::samba-dcerpcd /usr/lib*/samba/{,samba/}samba-dcerpcd {...}" a string ":samba-dcerpcd" is unpacked as a fully-qualified name and then passed to aa_splitn_fqname(). aa_splitn_fqname() treats ":samba-dcerpcd" as only containing a namespace. Thus it returns NULL for tmpname, meanwhile tmpns is non-NULL. Later aa_alloc_profile() crashes as the new profile name is NULL now. general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 6 PID: 1657 Comm: apparmor_parser Not tainted 6.7.0-rc2-dirty #16 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014 RIP: 0010:strlen+0x1e/0xa0 Call Trace: <TASK> ? strlen+0x1e/0xa0 aa_policy_init+0x1bb/0x230 aa_alloc_profile+0xb1/0x480 unpack_profile+0x3bc/0x4960 aa_unpack+0x309/0x15e0 aa_replace_profiles+0x213/0x33c0 policy_update+0x261/0x370 profile_replace+0x20e/0x2a0 vfs_write+0x2af/0xe00 ksys_write+0x126/0x250 do_syscall_64+0x46/0xf0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 </TASK> ---[ end trace 0000000000000000 ]--- RIP: 0010:strlen+0x1e/0xa0 It seems such behaviour of aa_splitn_fqname() is expected and checked in other places where it is called (e.g. aa_remove_profiles). Well, there is an explicit comment "a ns name without a following profile is allowed" inside. AFAICS, nothing can prevent unpacked "name" to be in form like ":samba-dcerpcd" - it is passed from userspace. Deny the whole profile set replacement in such case and inform user with EPROTO and an explaining message. Found by Linux Verification Center (linuxtesting.org) Fixes: 04dc715e24d0 ("apparmor: audit policy ns specified in policy load") Signed-off-by: Fedor Pchelkin <pchelkin(a)ispras.ru> Signed-off-by: John Johansen <john.johansen(a)canonical.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Xiang Yang <xiangyang3(a)huawei.com> --- security/apparmor/policy_unpack.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c index dbc83455d900..eb406ac595f8 100644 --- a/security/apparmor/policy_unpack.c +++ b/security/apparmor/policy_unpack.c @@ -826,6 +826,10 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name) tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len); if (tmpns) { + if (!tmpname) { + info = "empty profile name"; + goto fail; + } *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL); if (!*ns_name) { info = "out of memory"; -- 2.34.1

2 1

[PATCH OLK-5.10] apparmor: avoid crash when parsed profile name is empty
by Xiang Yang 05 Mar '24

05 Mar '24

From: Fedor Pchelkin <pchelkin(a)ispras.ru> stable inclusion from stable-v5.10.209 commit 5ff00408e5029d3550ee77f62dc15f1e15c47f87 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I932W7 CVE: CVE-2023-52443 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… ----------------------------------------------------- [ Upstream commit 55a8210c9e7d21ff2644809699765796d4bfb200 ] When processing a packed profile in unpack_profile() described like "profile :ns::samba-dcerpcd /usr/lib*/samba/{,samba/}samba-dcerpcd {...}" a string ":samba-dcerpcd" is unpacked as a fully-qualified name and then passed to aa_splitn_fqname(). aa_splitn_fqname() treats ":samba-dcerpcd" as only containing a namespace. Thus it returns NULL for tmpname, meanwhile tmpns is non-NULL. Later aa_alloc_profile() crashes as the new profile name is NULL now. general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 6 PID: 1657 Comm: apparmor_parser Not tainted 6.7.0-rc2-dirty #16 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.2-3-gd478f380-rebuilt.opensuse.org 04/01/2014 RIP: 0010:strlen+0x1e/0xa0 Call Trace: <TASK> ? strlen+0x1e/0xa0 aa_policy_init+0x1bb/0x230 aa_alloc_profile+0xb1/0x480 unpack_profile+0x3bc/0x4960 aa_unpack+0x309/0x15e0 aa_replace_profiles+0x213/0x33c0 policy_update+0x261/0x370 profile_replace+0x20e/0x2a0 vfs_write+0x2af/0xe00 ksys_write+0x126/0x250 do_syscall_64+0x46/0xf0 entry_SYSCALL_64_after_hwframe+0x6e/0x76 </TASK> ---[ end trace 0000000000000000 ]--- RIP: 0010:strlen+0x1e/0xa0 It seems such behaviour of aa_splitn_fqname() is expected and checked in other places where it is called (e.g. aa_remove_profiles). Well, there is an explicit comment "a ns name without a following profile is allowed" inside. AFAICS, nothing can prevent unpacked "name" to be in form like ":samba-dcerpcd" - it is passed from userspace. Deny the whole profile set replacement in such case and inform user with EPROTO and an explaining message. Found by Linux Verification Center (linuxtesting.org) Fixes: 04dc715e24d0 ("apparmor: audit policy ns specified in policy load") Signed-off-by: Fedor Pchelkin <pchelkin(a)ispras.ru> Signed-off-by: John Johansen <john.johansen(a)canonical.com> Signed-off-by: Sasha Levin <sashal(a)kernel.org> Signed-off-by: Xiang Yang <xiangyang3(a)huawei.com> --- security/apparmor/policy_unpack.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/security/apparmor/policy_unpack.c b/security/apparmor/policy_unpack.c index 10896d69c442..6c2a536173b5 100644 --- a/security/apparmor/policy_unpack.c +++ b/security/apparmor/policy_unpack.c @@ -696,6 +696,10 @@ static struct aa_profile *unpack_profile(struct aa_ext *e, char **ns_name) tmpname = aa_splitn_fqname(name, strlen(name), &tmpns, &ns_len); if (tmpns) { + if (!tmpname) { + info = "empty profile name"; + goto fail; + } *ns_name = kstrndup(tmpns, ns_len, GFP_KERNEL); if (!*ns_name) { info = "out of memory"; -- 2.34.1

2 1

[PATCH openEuler-1.0-LTS] perf/x86/lbr: Filter vsyscall addresses
by Luo Gengkun 05 Mar '24

05 Mar '24

From: JP Kobryn <inwardvessel(a)gmail.com> mainline inclusion from mainline-v6.6-rc6 commit e53899771a02f798d436655efbd9d4b46c0f9265 category: bugfix bugzilla: 189601 CVE: CVE-2023-52476 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id… -------------------------------- We found that a panic can occur when a vsyscall is made while LBR sampling is active. If the vsyscall is interrupted (NMI) for perf sampling, this call sequence can occur (most recent at top): __insn_get_emulate_prefix() insn_get_emulate_prefix() insn_get_prefixes() insn_get_opcode() decode_branch_type() get_branch_type() intel_pmu_lbr_filter() intel_pmu_handle_irq() perf_event_nmi_handler() Within __insn_get_emulate_prefix() at frame 0, a macro is called: peek_nbyte_next(insn_byte_t, insn, i) Within this macro, this dereference occurs: (insn)->next_byte Inspecting registers at this point, the value of the next_byte field is the address of the vsyscall made, for example the location of the vsyscall version of gettimeofday() at 0xffffffffff600000. The access to an address in the vsyscall region will trigger an oops due to an unhandled page fault. To fix the bug, filtering for vsyscalls can be done when determining the branch type. This patch will return a "none" branch if a kernel address if found to lie in the vsyscall region. Suggested-by: Alexei Starovoitov <ast(a)kernel.org> Signed-off-by: JP Kobryn <inwardvessel(a)gmail.com> Signed-off-by: Ingo Molnar <mingo(a)kernel.org> Cc: stable(a)vger.kernel.org Conflicts: arch/x86/events/utils.c Signed-off-by: Luo Gengkun <luogengkun2(a)huawei.com> --- arch/x86/events/intel/lbr.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/arch/x86/events/intel/lbr.c b/arch/x86/events/intel/lbr.c index a3dc3b5bc78d..1fb1ede03c40 100644 --- a/arch/x86/events/intel/lbr.c +++ b/arch/x86/events/intel/lbr.c @@ -5,6 +5,7 @@ #include <asm/perf_event.h> #include <asm/msr.h> #include <asm/insn.h> +#include <linux/mm.h> #include "../perf_event.h" @@ -894,9 +895,9 @@ static int branch_type(unsigned long from, unsigned long to, int abort) * The LBR logs any address in the IP, even if the IP just * faulted. This means userspace can control the from address. * Ensure we don't blindy read any address by validating it is - * a known text address. + * a known text address and not a vsyscall address. */ - if (kernel_text_address(from)) { + if (kernel_text_address(from) && !in_gate_area_no_mm(from)) { addr = (void *)from; /* * Assume we can get the maximum possible size -- 2.34.1

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