cpufreq: e_powersaver: Use struct_size() in kzalloc()
PATCH 1/1 cpufreq: e_powersaver: Use struct_size() in kzalloc()
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example:
struct foo {
int stuff;
void *entry[];
};instance = kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);
Instead of leaving these open-coded and prone to type mistakes, we can now use the new struct_size() helper:
instance = kzalloc(struct_size(instance, entry, count), GFP_KERNEL);
This code was detected with the help of Coccinelle.
--- drivers/cpufreq/e_powersaver.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)
drivers/cpufreq/e_powersaver.c +2 -3
@@ -323,9 +323,8 @@ static int eps_cpu_init(struct cpufreq_policy *policy) states =2 ;/* Allocate private data and frequency table for current cpu */ - centaur =kzalloc (sizeof (*centaur) - + (states +1 ) *sizeof (struct cpufreq_frequency_table ), -GFP_KERNEL ); + centaur =kzalloc (struct_size (centaur, freq_table, states +1 ), +GFP_KERNEL );if (!centaur)return -ENOMEM ; eps_cpu[0 ] = centaur;
Signature · 1 line
2.20.1
Quoted 29 lines · Gustavo A. R. Silva
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example:
struct foo { int stuff; void *entry[]; };instance =
kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);Instead of leaving these open-coded and prone to type mistakes, we can now use the new
struct_size()helper:instance =
kzalloc(struct_size(instance, entry, count), GFP_KERNEL);This code was detected with the help of Coccinelle.
Signed-off-by Gustavo A. R. Silva <[email protected]>--- drivers/cpufreq/e_powersaver.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)drivers/cpufreq/e_powersaver.c +0
-0@@ -323,9 +323,8 @@ static int eps_cpu_init(struct cpufreq_policy *policy) states =2 ;
drivers/cpufreq/e_powersaver.c static int eps_cpu_init(struct cpufreq_policy *policy) · line 330
Quoted 10 lines
drivers/cpufreq/e_powersaver.c +2
-3/* Allocate private data and frequency table for current cpu */ - centaur =kzalloc (sizeof (*centaur) - + (states +1 ) *sizeof (struct cpufreq_frequency_table ), -GFP_KERNEL ); + centaur =kzalloc (struct_size (centaur, freq_table, states +1 ), +GFP_KERNEL );if (!centaur)return -ENOMEM ; eps_cpu[0 ] = centaur;
Signature · 1 line
viresh
Quoted 31 lines · CET Viresh Kumar
Quoted 30 lines · Gustavo A. R. Silva
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example:
struct foo { int stuff; void *entry[]; };instance =
kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);Instead of leaving these open-coded and prone to type mistakes, we can now use the new
struct_size()helper:instance =
kzalloc(struct_size(instance, entry, count), GFP_KERNEL);This code was detected with the help of Coccinelle.
Signed-off-by Gustavo A. R. Silva <[email protected]>--- drivers/cpufreq/e_powersaver.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)drivers/cpufreq/e_powersaver.c +0
-0@@ -323,9 +323,8 @@ static int eps_cpu_init(struct cpufreq_policy *policy) states =2 ;
Quoted 11 lines
drivers/cpufreq/e_powersaver.c static int eps_cpu_init(struct cpufreq_policy *policy) · line 330
Quoted 9 lines
drivers/cpufreq/e_powersaver.c +2
-3/* Allocate private data and frequency table for current cpu */ - centaur =kzalloc (sizeof (*centaur) - + (states +1 ) *sizeof (struct cpufreq_frequency_table ), -GFP_KERNEL ); + centaur =kzalloc (struct_size (centaur, freq_table, states +1 ), +GFP_KERNEL );if (!centaur)return -ENOMEM ; eps_cpu[0 ] = centaur;Acked-by Viresh Kumar <[email protected]>
Patch applied, thanks!
Quoted 44 lines · Rafael J. Wysocki
Quoted 31 lines · CET Viresh Kumar
Quoted 30 lines · Gustavo A. R. Silva
One of the more common cases of allocation size calculations is finding the size of a structure that has a zero-sized array at the end, along with memory for some number of elements for that array. For example:
struct foo { int stuff; void *entry[]; };instance =
kzalloc(sizeof(struct foo) + sizeof(void *) * count, GFP_KERNEL);Instead of leaving these open-coded and prone to type mistakes, we can now use the new
struct_size()helper:instance =
kzalloc(struct_size(instance, entry, count), GFP_KERNEL);This code was detected with the help of Coccinelle.
Signed-off-by Gustavo A. R. Silva <[email protected]>--- drivers/cpufreq/e_powersaver.c | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-)drivers/cpufreq/e_powersaver.c +0
-0@@ -323,9 +323,8 @@ static int eps_cpu_init(struct cpufreq_policy *policy) states =2 ;Quoted 11 lines
drivers/cpufreq/e_powersaver.c static int eps_cpu_init(struct cpufreq_policy *policy) · line 330
Quoted 9 lines
drivers/cpufreq/e_powersaver.c +2
-3/* Allocate private data and frequency table for current cpu */ - centaur =kzalloc (sizeof (*centaur) - + (states +1 ) *sizeof (struct cpufreq_frequency_table ), -GFP_KERNEL ); + centaur =kzalloc (struct_size (centaur, freq_table, states +1 ), +GFP_KERNEL );if (!centaur)return -ENOMEM ; eps_cpu[0 ] = centaur;Acked-by Viresh Kumar <[email protected]>
Quoted 2 lines
Patch applied, thanks!
Thank you both, Viresh and Rafael.
--
Gustavo