Linux Kernel up to 5.10.109/5.15.32/5.16.18/5.17.1 clk_core_get_parent_by_index gcc_xo_gpll0[] null pointer dereference

Summaryinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 5.10.109/5.15.32/5.16.18/5.17.1. This vulnerability affects the function clk_core_get_parent_by_index. Performing a manipulation of the argument gcc_xo_gpll0[] results in null pointer dereference. This vulnerability was named CVE-2021-47647. There is no available exploit. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical has been found in Linux Kernel up to 5.10.109/5.15.32/5.16.18/5.17.1. This affects the function clk_core_get_parent_by_index. The manipulation of the argument gcc_xo_gpll0[] with an unknown input leads to a null pointer dereference vulnerability. CWE is classifying the issue as CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. This is going to have an impact on availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: clk: qcom: ipq8074: fix PCI-E clock oops Fix PCI-E clock related kernel oops that are caused by a missing clock parent. pcie0_rchng_clk_src has num_parents set to 2 but only one parent is actually set via parent_hws, it should also have "XO" defined. This will cause the kernel to panic on a NULL pointer in clk_core_get_parent_by_index(). So, to fix this utilize clk_parent_data to provide gcc_xo_gpll0 parent data. Since there is already an existing static const char * const gcc_xo_gpll0[] used to provide the same parents via parent_names convert those users to clk_parent_data as well. Without this earlycon is needed to even catch the OOPS as it will reset the board before serial is initialized with the following: [ 0.232279] Unable to handle kernel paging request at virtual address 0000a00000000000 [ 0.232322] Mem abort info: [ 0.239094] ESR = 0x96000004 [ 0.241778] EC = 0x25: DABT (current EL), IL = 32 bits [ 0.244908] SET = 0, FnV = 0 [ 0.250377] EA = 0, S1PTW = 0 [ 0.253236] FSC = 0x04: level 0 translation fault [ 0.256277] Data abort info: [ 0.261141] ISV = 0, ISS = 0x00000004 [ 0.264262] CM = 0, WnR = 0 [ 0.267820] [0000a00000000000] address between user and kernel address ranges [ 0.270954] Internal error: Oops: 96000004 [#1] SMP [ 0.278067] Modules linked in: [ 0.282751] CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.15.10 #0 [ 0.285882] Hardware name: Xiaomi AX3600 (DT) [ 0.292043] pstate: 20400005 (nzCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) [ 0.296299] pc : clk_core_get_parent_by_index+0x68/0xec [ 0.303067] lr : __clk_register+0x1d8/0x820 [ 0.308273] sp : ffffffc01111b7d0 [ 0.312438] x29: ffffffc01111b7d0 x28: 0000000000000000 x27: 0000000000000040 [ 0.315919] x26: 0000000000000002 x25: 0000000000000000 x24: ffffff8000308800 [ 0.323037] x23: ffffff8000308850 x22: ffffff8000308880 x21: ffffff8000308828 [ 0.330155] x20: 0000000000000028 x19: ffffff8000309700 x18: 0000000000000020 [ 0.337272] x17: 000000005cc86990 x16: 0000000000000004 x15: ffffff80001d9d0a [ 0.344391] x14: 0000000000000000 x13: 0000000000000000 x12: 0000000000000006 [ 0.351508] x11: 0000000000000003 x10: 0101010101010101 x9 : 0000000000000000 [ 0.358626] x8 : 7f7f7f7f7f7f7f7f x7 : 6468626f5e626266 x6 : 17000a3a403c1b06 [ 0.365744] x5 : 061b3c403a0a0017 x4 : 0000000000000000 x3 : 0000000000000001 [ 0.372863] x2 : 0000a00000000000 x1 : 0000000000000001 x0 : ffffff8000309700 [ 0.379982] Call trace: [ 0.387091] clk_core_get_parent_by_index+0x68/0xec [ 0.389351] __clk_register+0x1d8/0x820 [ 0.394210] devm_clk_hw_register+0x5c/0xe0 [ 0.398030] devm_clk_register_regmap+0x44/0x8c [ 0.402198] qcom_cc_really_probe+0x17c/0x1d0 [ 0.406711] qcom_cc_probe+0x34/0x44 [ 0.411224] gcc_ipq8074_probe+0x18/0x30 [ 0.414869] platform_probe+0x68/0xe0 [ 0.418776] really_probe.part.0+0x9c/0x30c [ 0.422336] __driver_probe_device+0x98/0x144 [ 0.426329] driver_probe_device+0x44/0x11c [ 0.430842] __device_attach_driver+0xb4/0x120 [ 0.434836] bus_for_each_drv+0x68/0xb0 [ 0.439349] __device_attach+0xb0/0x170 [ 0.443081] device_initial_probe+0x14/0x20 [ 0.446901] bus_probe_device+0x9c/0xa4 [ 0.451067] device_add+0x35c/0x834 [ 0.454886] of_device_add+0x54/0x64 [ 0.458360] of_platform_device_create_pdata+0xc0/0x100 [ 0.462181] of_platform_bus_create+0x114/0x370 [ 0.467128] of_platform_bus_create+0x15c/0x370 [ 0.471641] of_platform_populate+0x50/0xcc [ 0.476155] of_platform_default_populate_init+0xa8/0xc8 [ 0.480324] do_one_initcall+0x50/0x1b0 [ 0.485877] kernel_init_freeable+0x234/0x29c [ 0.489436] kernel_init+0x24/0x120 [ 0.493948] ret_from_fork+0x10/0x20 [ 0.497253] Code: d50323bf d65f03c0 f94002a2 b4000302 (f9400042) [ 0.501079] ---[ end trace 4ca7e1129da2abce ]---

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2021-47647 since 02/26/2025. The exploitability is told to be difficult. Technical details are known, but no exploit is available.

Upgrading to version 5.10.110, 5.15.33, 5.16.19 or 5.17.2 eliminates this vulnerability. Applying the patch 8b89c9e68a01a19a1dd689a42aa65d545e931899/41e360fa73a4c2f5b78f5ded78a5375b08c206a5/d02b3d4a8c525068bc5cfb4341e0023d8eb82ace/5a5576ad405c3c89fc9afb245c4dcc3e412b0aa9/bf8f5182b8f59309809b41c1d1730ed9ca6134b1 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2021-34658). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.10.109
• 5.15.0
• 5.15.1
• 5.15.2
• 5.15.3
• 5.15.4
• 5.15.5
• 5.15.6
• 5.15.7
• 5.15.8
• 5.15.9
• 5.15.10
• 5.15.11
• 5.15.12
• 5.15.13
• 5.15.14
• 5.15.15
• 5.15.16
• 5.15.17
• 5.15.18
• 5.15.19
• 5.15.20
• 5.15.21
• 5.15.22
• 5.15.23
• 5.15.24
• 5.15.25
• 5.15.26
• 5.15.27
• 5.15.28
• 5.15.29
• 5.15.30
• 5.15.31
• 5.15.32
• 5.16.0
• 5.16.1
• 5.16.2
• 5.16.3
• 5.16.4
• 5.16.5
• 5.16.6
• 5.16.7
• 5.16.8
• 5.16.9
• 5.16.10
• 5.16.11
• 5.16.12
• 5.16.13
• 5.16.14
• 5.16.15
• 5.16.16
• 5.16.17
• 5.16.18
• 5.17.0
• 5.17.1

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

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Sourcesinfo

Entryinfo

If you want to get the best quality for vulnerability data then you always have to consider VulDB.

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