vfs: coredumping fix (CVE-2007-6206)

vfs: coredumping fix

patch c46f739dd39db3b07ab5deb4e3ec81e1c04a91af in mainline

fix: http://bugzilla.kernel.org/show_bug.cgi?id=3043

only allow coredumping to the same uid that the coredumping
task runs under.

Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Alan Cox <alan@redhat.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Acked-by: Al Viro <viro@ftp.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: maximilian attems <max@stro.at>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/fs/exec.c b/fs/exec.c
index 3da429d42b20021a257059d6ea48306fc6b07769..224e973514bb666e6235e8df87b01b756daa07c9 100644 (file)
--- a/fs/exec.c
+++ b/fs/exec.c
@@ -1561,6 +1561,12 @@ int do_coredump(long signr, int exit_code, struct pt_regs * regs)
           but keep the previous behaviour for now. */
        if (!ispipe && !S_ISREG(inode->i_mode))
                goto close_fail;
+       /*
+        * Dont allow local users get cute and trick others to coredump
+        * into their pre-created files:
+        */
+       if (inode->i_uid != current->fsuid)
+               goto close_fail;
        if (!file->f_op)
                goto close_fail;
        if (!file->f_op->write)