procfs: call default get_unmapped_area on MMU-present architectures

Commit c4fe244857 ("sparc: fix PCI device proc file mmap(2)") added
proc_reg_get_unmapped_area in proc_reg_file_ops and
proc_reg_file_ops_no_compat, by which now mmap always returns EIO if
get_unmapped_area method is not defined for the target procfs file,
which causes regression of mmap on /proc/vmcore.

To address this issue, like get_unmapped_area(), call default
current->mm->get_unmapped_area on MMU-present architectures if
pde->proc_fops->get_unmapped_area, i.e.  the one in actual file
operation in the procfs file, is not defined.

Reported-by: Michael Holzheu <[email protected]>
Signed-off-by: HATAYAMA Daisuke <[email protected]>
Cc: Alexey Dobriyan <[email protected]>
Cc: David S. Miller <[email protected]>
Tested-by: Michael Holzheu <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
This commit is contained in:
HATAYAMA Daisuke authored and Linus Torvalds committed 2013-10-16 21:35:53 -07:00
1 parent 2cbe3b0af8
commit fad1a86e25
1 file changed
+6 -2
+6 -2
View File
@@ -289,9 +289,13 @@ static unsigned long proc_reg_get_unmapped_area(struct file *file, unsigned long
{
struct proc_dir_entry *pde = PDE(file_inode(file));
unsigned long rv = -EIO;
unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long);
unsigned long (*get_unmapped_area)(struct file *, unsigned long, unsigned long, unsigned long, unsigned long) = NULL;
if (use_pde(pde)) {
get_unmapped_area = pde->proc_fops->get_unmapped_area;
#ifdef CONFIG_MMU
get_unmapped_area = current->mm->get_unmapped_area;
#endif
if (pde->proc_fops->get_unmapped_area)
get_unmapped_area = pde->proc_fops->get_unmapped_area;
if (get_unmapped_area)
rv = get_unmapped_area(file, orig_addr, len, pgoff, flags);
unuse_pde(pde);