From: "Jan Beulich" <JBeulich@xxxxxxxx>
Subject: procfs: also fix proc_reg_get_unmapped_area() for !MMU case
Commit fad1a86e ("procfs: call default get_unmapped_area on MMU-present
architectures"), as its title says, took care of only the MMU case,
leaving the !MMU side still in the regressed state (returning -EIO in all
cases where pde->proc_fops->get_unmapped_area is NULL).
>From the fad1a86e changelog:
: Commit c4fe24485729 ("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.
Signed-off-by: Jan Beulich <jbeulich@xxxxxxxx>
Cc: HATAYAMA Daisuke <d.hatayama@xxxxxxxxxxxxxx>
Cc: Alexey Dobriyan <adobriyan@xxxxxxxxx>
Cc: David S. Miller <davem@xxxxxxxxxxxxx>
Cc: <stable@xxxxxxxxxxxxxxx> [3.12.x]
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
fs/proc/inode.c | 14 +++++++++-----
1 file changed, 9 insertions(+), 5 deletions(-)
diff -puN fs/proc/inode.c~procfs-also-fix-proc_reg_get_unmapped_area-for-mmu-case fs/proc/inode.c
--- a/fs/proc/inode.c~procfs-also-fix-proc_reg_get_unmapped_area-for-mmu-case
+++ a/fs/proc/inode.c
@@ -292,16 +292,20 @@ proc_reg_get_unmapped_area(struct file *
{
struct proc_dir_entry *pde = PDE(file_inode(file));
unsigned long rv = -EIO;
- unsigned long (*get_area)(struct file *, unsigned long, unsigned long,
- unsigned long, unsigned long) = NULL;
+
if (use_pde(pde)) {
+ typeof(proc_reg_get_unmapped_area) *get_area;
+
+ get_area = pde->proc_fops->get_unmapped_area;
#ifdef CONFIG_MMU
- get_area = current->mm->get_unmapped_area;
+ if (!get_area)
+ get_area = current->mm->get_unmapped_area;
#endif
- if (pde->proc_fops->get_unmapped_area)
- get_area = pde->proc_fops->get_unmapped_area;
+
if (get_area)
rv = get_area(file, orig_addr, len, pgoff, flags);
+ else
+ rv = orig_addr;
unuse_pde(pde);
}
return rv;
_
--
To unsubscribe from this list: send the line "unsubscribe stable" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html