Re: 2.6.25-rc8-mm1 - BUG in fs/jbd/transaction.c

James Morris
2008-04-06T23:56:28Z

On Fri, 4 Apr 2008, Stephen Smalley wrote:

>
> On Fri, 2008-04-04 at 10:02 +1100, James Morris wrote:
> > On Thu, 3 Apr 2008, Stephen Smalley wrote:
> >
> > > > > Try this patch, it will keep us from re-entering the fs when we aren't supposed
> > > > > to. cc'ing Eric Paris since he's the only selinux guy I know :). I don't think
> >
> > Please see the MAINTAINERS file.
> >
> > > > > any of the other allocations in here need to be fixed, but I didn't look too
> > > > > carefully.
> > > > >
> > > > > Signed-off-by: Josef Bacik <jbacik@redhat.com>
> >
> > Thanks, I'll push this to Linus, but note that further analysis is
> > required.
>
> Please review.

Looks good to me.

>
> More cases where SELinux must not re-enter the fs code.
> Called from the d_instantiate security hook.
>
> Signed-off-by: Stephen Smalley <sds@tycho.nsa.gov>
>
> ---
>
> security/selinux/hooks.c | 7 ++++---
> security/selinux/include/security.h | 3 ++-
> security/selinux/ss/services.c | 12 +++++++-----
> 3 files changed, 13 insertions(+), 9 deletions(-)
>
> diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
> index 41a049f..95b51b6 100644
> --- a/security/selinux/hooks.c
> +++ b/security/selinux/hooks.c
> @@ -1143,7 +1143,7 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
> }
>
> len = INITCONTEXTLEN;
> - context = kmalloc(len, GFP_KERNEL);
> + context = kmalloc(len, GFP_NOFS);
> if (!context) {
> rc = -ENOMEM;
> dput(dentry);
> @@ -1161,7 +1161,7 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
> }
> kfree(context);
> len = rc;
> - context = kmalloc(len, GFP_KERNEL);
> + context = kmalloc(len, GFP_NOFS);
> if (!context) {
> rc = -ENOMEM;
> dput(dentry);
> @@ -1185,7 +1185,8 @@ static int inode_doinit_with_dentry(struct inode *inode, struct dentry *opt_dent
> rc = 0;
> } else {
> rc = security_context_to_sid_default(context, rc, &sid,
> - sbsec->def_sid);
> + sbsec->def_sid,
> + GFP_NOFS);
> if (rc) {
> printk(KERN_WARNING "%s: context_to_sid(%s) "
> "returned %d for dev=%s ino=%ld\n",
> diff --git a/security/selinux/include/security.h b/security/selinux/include/security.h
> index f7d2f03..44e12ec 100644
> --- a/security/selinux/include/security.h
> +++ b/security/selinux/include/security.h
> @@ -86,7 +86,8 @@ int security_sid_to_context(u32 sid, char **scontext,
> int security_context_to_sid(char *scontext, u32 scontext_len,
> u32 *out_sid);
>
> -int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *out_sid, u32 def_sid);
> +int security_context_to_sid_default(char *scontext, u32 scontext_len,
> + u32 *out_sid, u32 def_sid, gfp_t gfp_flags);
>
> int security_get_user_sids(u32 callsid, char *username,
> u32 **sids, u32 *nel);
> diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c
> index f374186..3f2bad2 100644
> --- a/security/selinux/ss/services.c
> +++ b/security/selinux/ss/services.c
> @@ -680,7 +680,8 @@ out:
>
> }
>
> -static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
> +static int security_context_to_sid_core(char *scontext, u32 scontext_len,
> + u32 *sid, u32 def_sid, gfp_t gfp_flags)
> {
> char *scontext2;
> struct context context;
> @@ -709,7 +710,7 @@ static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *s
> null suffix to the copy to avoid problems with the existing
> attr package, which doesn't view the null terminator as part
> of the attribute value. */
> - scontext2 = kmalloc(scontext_len+1,GFP_KERNEL);
> + scontext2 = kmalloc(scontext_len+1, gfp_flags);
> if (!scontext2) {
> rc = -ENOMEM;
> goto out;
> @@ -809,7 +810,7 @@ out:
> int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
> {
> return security_context_to_sid_core(scontext, scontext_len,
> - sid, SECSID_NULL);
> + sid, SECSID_NULL, GFP_KERNEL);
> }
>
> /**
> @@ -829,10 +830,11 @@ int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid)
> * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient
> * memory is available, or 0 on success.
> */
> -int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid)
> +int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid,
> + u32 def_sid, gfp_t gfp_flags)
> {
> return security_context_to_sid_core(scontext, scontext_len,
> - sid, def_sid);
> + sid, def_sid, gfp_flags);
> }
>
> static int compute_sid_handle_invalid_context(
>
>

--
James Morris
<jmorris@namei.org>