diff options
author | Eric W. Biederman <ebiederm@aristanetworks.com> | 2010-09-20 09:57:03 +0200 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-10-22 19:16:43 +0200 |
commit | 38f49a5132f24d29236820eb5c7dd956e47f94a3 (patch) | |
tree | eb2d3184996d01babcf3689dd20d626f731d340a /fs/sysfs | |
parent | sysfs: Fail bin file mmap if vma close is implemented. (diff) | |
download | linux-38f49a5132f24d29236820eb5c7dd956e47f94a3.tar.xz linux-38f49a5132f24d29236820eb5c7dd956e47f94a3.zip |
sysfs: only access bin file vm_ops with the active lock
bb->vm_ops is a cached copy of the vm_ops of the underlying
sysfs bin file, which means that after sysfs_bin_remove_file
completes it is only longer valid to deference bb->vm_ops.
So move all of the tests of bb->vm_ops inside of where
we hold the sysfs active lock.
Signed-off-by: Eric W. Biederman <ebiederm@aristanetworks.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'fs/sysfs')
-rw-r--r-- | fs/sysfs/bin.c | 42 |
1 files changed, 26 insertions, 16 deletions
diff --git a/fs/sysfs/bin.c b/fs/sysfs/bin.c index d31d7b7d5426..a4759833d62d 100644 --- a/fs/sysfs/bin.c +++ b/fs/sysfs/bin.c @@ -179,13 +179,14 @@ static void bin_vma_open(struct vm_area_struct *vma) struct bin_buffer *bb = file->private_data; struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; - if (!bb->vm_ops || !bb->vm_ops->open) + if (!bb->vm_ops) return; if (!sysfs_get_active(attr_sd)) return; - bb->vm_ops->open(vma); + if (bb->vm_ops->open) + bb->vm_ops->open(vma); sysfs_put_active(attr_sd); } @@ -197,13 +198,15 @@ static int bin_fault(struct vm_area_struct *vma, struct vm_fault *vmf) struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; int ret; - if (!bb->vm_ops || !bb->vm_ops->fault) + if (!bb->vm_ops) return VM_FAULT_SIGBUS; if (!sysfs_get_active(attr_sd)) return VM_FAULT_SIGBUS; - ret = bb->vm_ops->fault(vma, vmf); + ret = VM_FAULT_SIGBUS; + if (bb->vm_ops->fault) + ret = bb->vm_ops->fault(vma, vmf); sysfs_put_active(attr_sd); return ret; @@ -219,13 +222,12 @@ static int bin_page_mkwrite(struct vm_area_struct *vma, struct vm_fault *vmf) if (!bb->vm_ops) return VM_FAULT_SIGBUS; - if (!bb->vm_ops->page_mkwrite) - return 0; - if (!sysfs_get_active(attr_sd)) return VM_FAULT_SIGBUS; - ret = bb->vm_ops->page_mkwrite(vma, vmf); + ret = 0; + if (bb->vm_ops->page_mkwrite) + ret = bb->vm_ops->page_mkwrite(vma, vmf); sysfs_put_active(attr_sd); return ret; @@ -239,13 +241,15 @@ static int bin_access(struct vm_area_struct *vma, unsigned long addr, struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; int ret; - if (!bb->vm_ops || !bb->vm_ops->access) + if (!bb->vm_ops) return -EINVAL; if (!sysfs_get_active(attr_sd)) return -EINVAL; - ret = bb->vm_ops->access(vma, addr, buf, len, write); + ret = -EINVAL; + if (bb->vm_ops->access) + ret = bb->vm_ops->access(vma, addr, buf, len, write); sysfs_put_active(attr_sd); return ret; @@ -259,13 +263,15 @@ static int bin_set_policy(struct vm_area_struct *vma, struct mempolicy *new) struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; int ret; - if (!bb->vm_ops || !bb->vm_ops->set_policy) + if (!bb->vm_ops) return 0; if (!sysfs_get_active(attr_sd)) return -EINVAL; - ret = bb->vm_ops->set_policy(vma, new); + ret = 0; + if (bb->vm_ops->set_policy) + ret = bb->vm_ops->set_policy(vma, new); sysfs_put_active(attr_sd); return ret; @@ -279,13 +285,15 @@ static struct mempolicy *bin_get_policy(struct vm_area_struct *vma, struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; struct mempolicy *pol; - if (!bb->vm_ops || !bb->vm_ops->get_policy) + if (!bb->vm_ops) return vma->vm_policy; if (!sysfs_get_active(attr_sd)) return vma->vm_policy; - pol = bb->vm_ops->get_policy(vma, addr); + pol = vma->vm_policy; + if (bb->vm_ops->get_policy) + pol = bb->vm_ops->get_policy(vma, addr); sysfs_put_active(attr_sd); return pol; @@ -299,13 +307,15 @@ static int bin_migrate(struct vm_area_struct *vma, const nodemask_t *from, struct sysfs_dirent *attr_sd = file->f_path.dentry->d_fsdata; int ret; - if (!bb->vm_ops || !bb->vm_ops->migrate) + if (!bb->vm_ops) return 0; if (!sysfs_get_active(attr_sd)) return 0; - ret = bb->vm_ops->migrate(vma, from, to, flags); + ret = 0; + if (bb->vm_ops->migrate) + ret = bb->vm_ops->migrate(vma, from, to, flags); sysfs_put_active(attr_sd); return ret; |