Re: [PATCH 2/7] fallocate() implementation in i386, x86_64 and powerpc

David Patrick Quigley
2007-07-12T13:16:55Z

From: David P. Quigley <dpquigl@tycho.nsa.gov>

Revalidate the write permissions for fallocate(2), in case security policy has
changed since the files were opened.

Signed-off-by: David P. Quigley <dpquigl@tycho.nsa.gov>

fs/open.c | 3 +++
1 file changed, 3 insertions(+)

diff -uprN -X linux-2.6.22/Documentation/dontdiff linux-2.6.22-fallocate/fs/open.c linux-2.6.22-fallocate-selinux/fs/open.c
--- linux-2.6.22-fallocate/fs/open.c 2007-07-11 15:51:10.000000000 -0400
+++ linux-2.6.22-fallocate-selinux/fs/open.c 2007-07-11 16:10:43.000000000 -0400
@@ -411,6 +411,9 @@ asmlinkage long sys_fallocate(int fd, in
goto out;
if (!(file->f_mode & FMODE_WRITE))
goto out_fput;
+ ret = security_file_permission(file, MAY_WRITE);
+ if (ret)
+ goto out_fput;

inode = file->f_path.dentry->d_inode;