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| author | HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com> | 2013-10-16 22:47:05 +0200 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-10-17 06:35:53 +0200 |
| commit | fad1a86e25e0a1f85635ed06ef62ddadd5b8fa4c (patch) | |
| tree | d616a4153716c2e33a39b5073d1a5ec00e636008 | |
| parent | procfs: fix unintended truncation of returned mapped address (diff) | |
| download | linux-fad1a86e25e0a1f85635ed06ef62ddadd5b8fa4c.tar.xz linux-fad1a86e25e0a1f85635ed06ef62ddadd5b8fa4c.zip | |
procfs: call default get_unmapped_area on MMU-present architectures
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.
Reported-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: HATAYAMA Daisuke <d.hatayama@jp.fujitsu.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: David S. Miller <davem@davemloft.net>
Tested-by: Michael Holzheu <holzheu@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | fs/proc/inode.c | 8 |
1 files changed, 6 insertions, 2 deletions
diff --git a/fs/proc/inode.c b/fs/proc/inode.c index 6c501c4d996d..8eaa1ba793fc 100644 --- a/fs/proc/inode.c +++ b/fs/proc/inode.c @@ -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); |