4.19-stable review patch. If anyone has any objections, please let me know.
------------------
From: Luo Qiu luoqiu@kylinsec.com.cn
[ Upstream commit 109aa654f85c5141e813b2cd1bd36d90be678407 ]
Fix a kernel crash with the below call trace when the SCPI firmware returns OPP count of zero.
dvfs_info.opp_count may be zero on some platforms during the reboot test, and the kernel will crash after dereferencing the pointer to kcalloc(info->count, sizeof(*opp), GFP_KERNEL).
| Unable to handle kernel NULL pointer dereference at virtual address 0000000000000028 | Mem abort info: | ESR = 0x96000004 | Exception class = DABT (current EL), IL = 32 bits | SET = 0, FnV = 0 | EA = 0, S1PTW = 0 | Data abort info: | ISV = 0, ISS = 0x00000004 | CM = 0, WnR = 0 | user pgtable: 4k pages, 48-bit VAs, pgdp = 00000000faefa08c | [0000000000000028] pgd=0000000000000000 | Internal error: Oops: 96000004 [#1] SMP | scpi-hwmon: probe of PHYT000D:00 failed with error -110 | Process systemd-udevd (pid: 1701, stack limit = 0x00000000aaede86c) | CPU: 2 PID: 1701 Comm: systemd-udevd Not tainted 4.19.90+ #1 | Hardware name: PHYTIUM LTD Phytium FT2000/4/Phytium FT2000/4, BIOS | pstate: 60000005 (nZCv daif -PAN -UAO) | pc : scpi_dvfs_recalc_rate+0x40/0x58 [clk_scpi] | lr : clk_register+0x438/0x720 | Call trace: | scpi_dvfs_recalc_rate+0x40/0x58 [clk_scpi] | devm_clk_hw_register+0x50/0xa0 | scpi_clk_ops_init.isra.2+0xa0/0x138 [clk_scpi] | scpi_clocks_probe+0x528/0x70c [clk_scpi] | platform_drv_probe+0x58/0xa8 | really_probe+0x260/0x3d0 | driver_probe_device+0x12c/0x148 | device_driver_attach+0x74/0x98 | __driver_attach+0xb4/0xe8 | bus_for_each_dev+0x88/0xe0 | driver_attach+0x30/0x40 | bus_add_driver+0x178/0x2b0 | driver_register+0x64/0x118 | __platform_driver_register+0x54/0x60 | scpi_clocks_driver_init+0x24/0x1000 [clk_scpi] | do_one_initcall+0x54/0x220 | do_init_module+0x54/0x1c8 | load_module+0x14a4/0x1668 | __se_sys_finit_module+0xf8/0x110 | __arm64_sys_finit_module+0x24/0x30 | el0_svc_common+0x78/0x170 | el0_svc_handler+0x38/0x78 | el0_svc+0x8/0x340 | Code: 937d7c00 a94153f3 a8c27bfd f9400421 (b8606820) | ---[ end trace 06feb22469d89fa8 ]--- | Kernel panic - not syncing: Fatal exception | SMP: stopping secondary CPUs | Kernel Offset: disabled | CPU features: 0x10,a0002008 | Memory Limit: none
Fixes: 8cb7cf56c9fe ("firmware: add support for ARM System Control and Power Interface(SCPI) protocol") Signed-off-by: Luo Qiu luoqiu@kylinsec.com.cn Message-Id: 55A2F7A784391686+20241101032115.275977-1-luoqiu@kylinsec.com.cn Signed-off-by: Sudeep Holla sudeep.holla@arm.com Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/firmware/arm_scpi.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/firmware/arm_scpi.c b/drivers/firmware/arm_scpi.c index 1ce27bb9deada..2745a596e1d18 100644 --- a/drivers/firmware/arm_scpi.c +++ b/drivers/firmware/arm_scpi.c @@ -638,6 +638,9 @@ static struct scpi_dvfs_info *scpi_dvfs_get_info(u8 domain) if (ret) return ERR_PTR(ret);
+ if (!buf.opp_count) + return ERR_PTR(-ENOENT); + info = kmalloc(sizeof(*info), GFP_KERNEL); if (!info) return ERR_PTR(-ENOMEM);