diff mbox series

[v5,bpf-next,07/11] bpf: Add a common helper bpf_copy_to_user()

Message ID 20230623141546.3751-8-laoar.shao@gmail.com (mailing list archive)
State Superseded
Delegated to: BPF
Headers show
Series bpf: Support ->fill_link_info for kprobe_multi and perf_event links | expand

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bpf/vmtest-bpf-next-VM_Test-12 success Logs for test_progs on s390x with gcc
bpf/vmtest-bpf-next-VM_Test-8 success Logs for test_maps on s390x with gcc
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for bpf-next, async
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 10 this patch: 10
netdev/cc_maintainers success CCed 12 of 12 maintainers
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 10 this patch: 10
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 46 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Yafang Shao June 23, 2023, 2:15 p.m. UTC 
Add a common helper bpf_copy_to_user(), which will be used at multiple
places.
No functional change.

Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
---
 kernel/bpf/syscall.c | 34 ++++++++++++++++++++--------------
 1 file changed, 20 insertions(+), 14 deletions(-)
diff mbox series

Patch

diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c
index a75c54b..f3e2d4e 100644
--- a/kernel/bpf/syscall.c
+++ b/kernel/bpf/syscall.c
@@ -3291,6 +3291,25 @@  static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
 		   raw_tp_link->btp->tp->name);
 }
 
+static int bpf_copy_to_user(char __user *ubuf, const char *buf, u32 ulen,
+			    u32 len)
+{
+	if (ulen >= len + 1) {
+		if (copy_to_user(ubuf, buf, len + 1))
+			return -EFAULT;
+	} else {
+		char zero = '\0';
+
+		if (copy_to_user(ubuf, buf, ulen - 1))
+			return -EFAULT;
+		if (put_user(zero, ubuf + ulen - 1))
+			return -EFAULT;
+		return -ENOSPC;
+	}
+
+	return 0;
+}
+
 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
 					  struct bpf_link_info *info)
 {
@@ -3309,20 +3328,7 @@  static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
 	if (!ubuf)
 		return 0;
 
-	if (ulen >= tp_len + 1) {
-		if (copy_to_user(ubuf, tp_name, tp_len + 1))
-			return -EFAULT;
-	} else {
-		char zero = '\0';
-
-		if (copy_to_user(ubuf, tp_name, ulen - 1))
-			return -EFAULT;
-		if (put_user(zero, ubuf + ulen - 1))
-			return -EFAULT;
-		return -ENOSPC;
-	}
-
-	return 0;
+	return bpf_copy_to_user(ubuf, tp_name, ulen, tp_len);
 }
 
 static const struct bpf_link_ops bpf_raw_tp_link_lops = {