[PATCH] perf/core: Remove size arguments when calling strscpy()

[PATCH] perf/core: Remove size arguments when calling strscpy()

[Thorsten Blum]

The size parameter is optional and strscpy() automatically determines
the length of the destination buffer using sizeof() if the argument is
omitted. This makes the explicit sizeof() calls unnecessary.

Furthermore, KSYM_NAME_LEN is equal to sizeof(name) and can also be
removed. Remove them to shorten and simplify the code.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
---
 kernel/events/core.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 823aa0824916..e4b071fc7d74 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8589,7 +8589,7 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
 	unsigned int size;
 
 	memset(comm, 0, sizeof(comm));
-	strscpy(comm, comm_event->task->comm, sizeof(comm));
+	strscpy(comm, comm_event->task->comm);
 	size = ALIGN(strlen(comm)+1, sizeof(u64));
 
 	comm_event->comm = comm;
@@ -9033,7 +9033,7 @@ static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
 	}
 
 cpy_name:
-	strscpy(tmp, name, sizeof(tmp));
+	strscpy(tmp, name);
 	name = tmp;
 got_name:
 	/*
@@ -9457,7 +9457,7 @@ void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister,
 	    ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN)
 		goto err;
 
-	strscpy(name, sym, KSYM_NAME_LEN);
+	strscpy(name, sym);
 	name_len = strlen(name) + 1;
 	while (!IS_ALIGNED(name_len, sizeof(u64)))
 		name[name_len++] = '\0';
-- 
2.48.1

[tip: perf/core] perf/core: Remove optional 'size' arguments from strscpy() calls

[tip-bot2 for Thorsten Blum]

The following commit has been merged into the perf/core branch of tip:

Commit-ID:     fd3f5d385a52531589c8a7a26d9e108aa1d3f52e
Gitweb:        https://git.kernel.org/tip/fd3f5d385a52531589c8a7a26d9e108aa1d3f52e
Author:        Thorsten Blum <thorsten.blum@linux.dev>
AuthorDate:    Mon, 10 Mar 2025 20:23:35 +01:00
Committer:     Ingo Molnar <mingo@kernel.org>
CommitterDate: Mon, 10 Mar 2025 20:50:30 +01:00

perf/core: Remove optional 'size' arguments from strscpy() calls

The 'size' parameter is optional and strscpy() automatically determines
the length of the destination buffer using sizeof() if the argument is
omitted. This makes the explicit sizeof() calls unnecessary.

Furthermore, KSYM_NAME_LEN is equal to sizeof(name) and can also be
removed. Remove them to shorten and simplify the code.

Signed-off-by: Thorsten Blum <thorsten.blum@linux.dev>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20250310192336.442994-1-thorsten.blum@linux.dev
---
 kernel/events/core.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index f159dba..e7d0b05 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -8665,7 +8665,7 @@ static void perf_event_comm_event(struct perf_comm_event *comm_event)
 	unsigned int size;
 
 	memset(comm, 0, sizeof(comm));
-	strscpy(comm, comm_event->task->comm, sizeof(comm));
+	strscpy(comm, comm_event->task->comm);
 	size = ALIGN(strlen(comm)+1, sizeof(u64));
 
 	comm_event->comm = comm;
@@ -9109,7 +9109,7 @@ static void perf_event_mmap_event(struct perf_mmap_event *mmap_event)
 	}
 
 cpy_name:
-	strscpy(tmp, name, sizeof(tmp));
+	strscpy(tmp, name);
 	name = tmp;
 got_name:
 	/*
@@ -9533,7 +9533,7 @@ void perf_event_ksymbol(u16 ksym_type, u64 addr, u32 len, bool unregister,
 	    ksym_type == PERF_RECORD_KSYMBOL_TYPE_UNKNOWN)
 		goto err;
 
-	strscpy(name, sym, KSYM_NAME_LEN);
+	strscpy(name, sym);
 	name_len = strlen(name) + 1;
 	while (!IS_ALIGNED(name_len, sizeof(u64)))
 		name[name_len++] = '\0';