From: Sung-hun Kim sfoon.kim@samsung.com
commit e400be674a1a40e9dcb2e95f84d6c1fd2d88f31d upstream.
Since the commit 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops") is applied to the kernel, splice() and sendfile() calls on the trace file (/sys/kernel/debug/tracing /trace) return EINVAL.
This patch restores these system calls by initializing splice_read in file_operations of the trace file. This patch only enables such functionalities for the read case.
Link: https://lore.kernel.org/linux-trace-kernel/20230314013707.28814-1-sfoon.kim@...
Cc: stable@vger.kernel.org Fixes: 36e2c7421f02 ("fs: don't allow splice read/write without explicit ops") Signed-off-by: Sung-hun Kim sfoon.kim@samsung.com Signed-off-by: Steven Rostedt (Google) rostedt@goodmis.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- kernel/trace/trace.c | 2 ++ 1 file changed, 2 insertions(+)
--- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -4705,6 +4705,8 @@ loff_t tracing_lseek(struct file *file, static const struct file_operations tracing_fops = { .open = tracing_open, .read = seq_read, + .read_iter = seq_read_iter, + .splice_read = generic_file_splice_read, .write = tracing_write_stub, .llseek = tracing_lseek, .release = tracing_release,