cpufreq: brcmstb-avs-cpufreq: Fix -Warray-bounds bug
authorGustavo A. R. Silva <gustavoars@kernel.org>
Tue, 1 Aug 2023 03:15:48 +0000 (21:15 -0600)
committerViresh Kumar <viresh.kumar@linaro.org>
Thu, 3 Aug 2023 05:55:04 +0000 (11:25 +0530)
commite520d0b6be950ce3738cf4b9bd3b392be818f1dc
tree316c61b8d291961c6cf61d0886bab6415c370c21
parent6b6349d0d685fc3032455b43fce57f374819fb54
cpufreq: brcmstb-avs-cpufreq: Fix -Warray-bounds bug

Allocate extra space for terminating element at:

drivers/cpufreq/brcmstb-avs-cpufreq.c:
449         table[i].frequency = CPUFREQ_TABLE_END;

and add code comment to make this clear.

This fixes the following -Warray-bounds warning seen after building
ARM with multi_v7_defconfig (GCC 13):
In function 'brcm_avs_get_freq_table',
    inlined from 'brcm_avs_cpufreq_init' at drivers/cpufreq/brcmstb-avs-cpufreq.c:623:15:
drivers/cpufreq/brcmstb-avs-cpufreq.c:449:28: warning: array subscript 5 is outside array bounds of 'void[60]' [-Warray-bounds=]
  449 |         table[i].frequency = CPUFREQ_TABLE_END;
In file included from include/linux/node.h:18,
                 from include/linux/cpu.h:17,
                 from include/linux/cpufreq.h:12,
                 from drivers/cpufreq/brcmstb-avs-cpufreq.c:44:
In function 'devm_kmalloc_array',
    inlined from 'devm_kcalloc' at include/linux/device.h:328:9,
    inlined from 'brcm_avs_get_freq_table' at drivers/cpufreq/brcmstb-avs-cpufreq.c:437:10,
    inlined from 'brcm_avs_cpufreq_init' at drivers/cpufreq/brcmstb-avs-cpufreq.c:623:15:
include/linux/device.h:323:16: note: at offset 60 into object of size 60 allocated by 'devm_kmalloc'
  323 |         return devm_kmalloc(dev, bytes, flags);
      |                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This helps with the ongoing efforts to tighten the FORTIFY_SOURCE
routines on memcpy() and help us make progress towards globally
enabling -Warray-bounds.

Link: https://github.com/KSPP/linux/issues/324
Fixes: de322e085995 ("cpufreq: brcmstb-avs-cpufreq: AVS CPUfreq driver for Broadcom STB SoCs")
Cc: stable@vger.kernel.org
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Reviewed-by: Florian Fainelli <florian.fainelli@broadcom.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
drivers/cpufreq/brcmstb-avs-cpufreq.c