security: revalidate rw permissions for sys_splice and sys_vmsplice (29ce2058) · Commits · 戴 / test

Revalidate read/write permissions for splice(2) and vmslice(2), in case security policy has changed since the files were opened. Acked-by:

fs/splice.c

+9 −0

Original line number	Diff line number	Diff line
		@@ -28,6 +28,7 @@
		#include <linux/module.h>
		#include <linux/syscalls.h>
		#include <linux/uio.h>
		#include <linux/security.h>

		/*
		* Attempt to steal a page from a pipe buffer. This should perhaps go into
		@@ -961,6 +962,10 @@ static long do_splice_from(struct pipe_inode_info pipe, struct file out,
		if (unlikely(ret < 0))
		return ret;

		ret = security_file_permission(out, MAY_WRITE);
		if (unlikely(ret < 0))
		return ret;

		return out->f_op->splice_write(pipe, out, ppos, len, flags);
		}

		@@ -983,6 +988,10 @@ static long do_splice_to(struct file in, loff_t ppos,
		if (unlikely(ret < 0))
		return ret;

		ret = security_file_permission(in, MAY_READ);
		if (unlikely(ret < 0))
		return ret;

		return in->f_op->splice_read(in, ppos, pipe, len, flags);
		}