busybox/examples/linux-2.6.30_proc_self_exe.patch
Denys Vlasenko cf4e503875 Added kernel patch for /proc/self/exe to examples
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
2009-07-02 12:04:50 +02:00

35 lines
966 B
Diff

This patch makes /proc/self/exe executable even if proc
is not mounted. It is especially useful on NOMMU arches.
diff -urp ../linux-2.6.30.org/fs/exec.c linux-2.6.30/fs/exec.c
--- ../linux-2.6.30.org/fs/exec.c 2009-06-10 05:05:27.000000000 +0200
+++ linux-2.6.30/fs/exec.c 2009-06-25 00:20:13.000000000 +0200
@@ -652,9 +652,25 @@ struct file *open_exec(const char *name)
file = do_filp_open(AT_FDCWD, name,
O_LARGEFILE | O_RDONLY | FMODE_EXEC, 0,
MAY_EXEC | MAY_OPEN);
- if (IS_ERR(file))
- goto out;
+ if (IS_ERR(file)) {
+ if ((PTR_ERR(file) == -ENOENT || PTR_ERR(file) == -EACCES)
+ && strcmp(name, "/proc/self/exe") == 0
+ ) {
+ struct file *sv = file;
+ struct mm_struct *mm;
+ mm = get_task_mm(current);
+ if (!mm)
+ goto out;
+ file = get_mm_exe_file(mm);
+ mmput(mm);
+ if (file)
+ goto ok;
+ file = sv;
+ }
+ goto out;
+ }
+ok:
err = -EACCES;
if (!S_ISREG(file->f_path.dentry->d_inode->i_mode))
goto exit;