Re: [PATCH v2] KEYS: always initialize keyring_index_key::desc_len

2019-02-19 Thread Eric Biggers
On Thu, Feb 07, 2019 at 03:35:29PM -0800, Eric Biggers wrote:
> On Thu, Jan 10, 2019 at 12:27:46PM -0800, Eric Biggers wrote:
> > On Wed, Nov 28, 2018 at 03:19:41PM -0800, Eric Biggers wrote:
> > > On Fri, Nov 02, 2018 at 06:58:54PM -0700, Eric Biggers wrote:
> > > > From: Eric Biggers 
> > > > 
> > > > syzbot hit the 'BUG_ON(index_key->desc_len == 0);' in __key_link_begin()
> > > > called from construct_alloc_key() during sys_request_key(), because the
> > > > length of the key description was never calculated.
> > > > 
> > > > The problem is that we rely on ->desc_len being initialized by
> > > > search_process_keyrings(), specifically by search_nested_keyrings().
> > > > But, if the process isn't subscribed to any keyrings that never happens.
> > > > 
> > > > Fix it by always initializing keyring_index_key::desc_len as soon as the
> > > > description is set, like we already do in some places.
> > > > 
> > > > The following program reproduces the BUG_ON() when it's run as root and
> > > > no session keyring has been installed.  If it doesn't work, try removing
> > > > pam_keyinit.so from /etc/pam.d/login and rebooting.
> > > > 
> > > > #include 
> > > > #include 
> > > > #include 
> > > > 
> > > > int main(void)
> > > > {
> > > > int id = add_key("keyring", "syz", NULL, 0, 
> > > > KEY_SPEC_USER_KEYRING);
> > > > 
> > > > keyctl_setperm(id, KEY_OTH_WRITE);
> > > > setreuid(5000, 5000);
> > > > request_key("user", "desc", "", id);
> > > > }
> > > > 
> > > > Reported-by: syzbot+ec24e95ea483de0a2...@syzkaller.appspotmail.com
> > > > Fixes: b2a4df200d57 ("KEYS: Expand the capacity of a keyring")
> > > > Cc:  # v3.13+
> > > > Signed-off-by: Eric Biggers 
> > > > ---
> > > > 
> > > > v2: In proc_keys_show(), assign index_key directly
> > > > 
> > > >  security/keys/keyring.c  | 4 +---
> > > >  security/keys/proc.c | 3 +--
> > > >  security/keys/request_key.c  | 1 +
> > > >  security/keys/request_key_auth.c | 2 +-
> > > >  4 files changed, 4 insertions(+), 6 deletions(-)
> > > > 
> > > > diff --git a/security/keys/keyring.c b/security/keys/keyring.c
> > > > index 41bcf57e96f21..99a55145ddcd2 100644
> > > > --- a/security/keys/keyring.c
> > > > +++ b/security/keys/keyring.c
> > > > @@ -661,9 +661,6 @@ static bool search_nested_keyrings(struct key 
> > > > *keyring,
> > > > BUG_ON((ctx->flags & STATE_CHECKS) == 0 ||
> > > >(ctx->flags & STATE_CHECKS) == STATE_CHECKS);
> > > >  
> > > > -   if (ctx->index_key.description)
> > > > -   ctx->index_key.desc_len = 
> > > > strlen(ctx->index_key.description);
> > > > -
> > > > /* Check to see if this top-level keyring is what we are 
> > > > looking for
> > > >  * and whether it is valid or not.
> > > >  */
> > > > @@ -914,6 +911,7 @@ key_ref_t keyring_search(key_ref_t keyring,
> > > > struct keyring_search_context ctx = {
> > > > .index_key.type = type,
> > > > .index_key.description  = description,
> > > > +   .index_key.desc_len = strlen(description),
> > > > .cred   = current_cred(),
> > > > .match_data.cmp = key_default_cmp,
> > > > .match_data.raw_data= description,
> > > > diff --git a/security/keys/proc.c b/security/keys/proc.c
> > > > index 5af2934965d80..d38be9db2cc07 100644
> > > > --- a/security/keys/proc.c
> > > > +++ b/security/keys/proc.c
> > > > @@ -166,8 +166,7 @@ static int proc_keys_show(struct seq_file *m, void 
> > > > *v)
> > > > int rc;
> > > >  
> > > > struct keyring_search_context ctx = {
> > > > -   .index_key.type = key->type,
> > > > -   .index_key.description  = key->description,
> > > > +   .index_key  = key->index_key,
> > > > .cred   = m->file->f_cred,
> > > > .match_data.cmp = lookup_user_key_possessed,
> > > > .match_data.raw_data= key,
> > > > diff --git a/security/keys/request_key.c b/security/keys/request_key.c
> > > > index 114f7408feee6..7385536986497 100644
> > > > --- a/security/keys/request_key.c
> > > > +++ b/security/keys/request_key.c
> > > > @@ -545,6 +545,7 @@ struct key *request_key_and_link(struct key_type 
> > > > *type,
> > > > struct keyring_search_context ctx = {
> > > > .index_key.type = type,
> > > > .index_key.description  = description,
> > > > +   .index_key.desc_len = strlen(description),
> > > > .cred   = current_cred(),
> > > > .match_data.cmp = key_default_cmp,
> > > > .match_data.raw_data= description,
> > > > diff --git a/security/keys/request_key_auth.c 
> > > > b/security/keys/request_key_auth.c
> > > > index 

Re: [PATCH v2] KEYS: always initialize keyring_index_key::desc_len

2019-02-07 Thread Eric Biggers
On Thu, Jan 10, 2019 at 12:27:46PM -0800, Eric Biggers wrote:
> On Wed, Nov 28, 2018 at 03:19:41PM -0800, Eric Biggers wrote:
> > On Fri, Nov 02, 2018 at 06:58:54PM -0700, Eric Biggers wrote:
> > > From: Eric Biggers 
> > > 
> > > syzbot hit the 'BUG_ON(index_key->desc_len == 0);' in __key_link_begin()
> > > called from construct_alloc_key() during sys_request_key(), because the
> > > length of the key description was never calculated.
> > > 
> > > The problem is that we rely on ->desc_len being initialized by
> > > search_process_keyrings(), specifically by search_nested_keyrings().
> > > But, if the process isn't subscribed to any keyrings that never happens.
> > > 
> > > Fix it by always initializing keyring_index_key::desc_len as soon as the
> > > description is set, like we already do in some places.
> > > 
> > > The following program reproduces the BUG_ON() when it's run as root and
> > > no session keyring has been installed.  If it doesn't work, try removing
> > > pam_keyinit.so from /etc/pam.d/login and rebooting.
> > > 
> > > #include 
> > > #include 
> > > #include 
> > > 
> > > int main(void)
> > > {
> > > int id = add_key("keyring", "syz", NULL, 0, 
> > > KEY_SPEC_USER_KEYRING);
> > > 
> > > keyctl_setperm(id, KEY_OTH_WRITE);
> > > setreuid(5000, 5000);
> > > request_key("user", "desc", "", id);
> > > }
> > > 
> > > Reported-by: syzbot+ec24e95ea483de0a2...@syzkaller.appspotmail.com
> > > Fixes: b2a4df200d57 ("KEYS: Expand the capacity of a keyring")
> > > Cc:  # v3.13+
> > > Signed-off-by: Eric Biggers 
> > > ---
> > > 
> > > v2: In proc_keys_show(), assign index_key directly
> > > 
> > >  security/keys/keyring.c  | 4 +---
> > >  security/keys/proc.c | 3 +--
> > >  security/keys/request_key.c  | 1 +
> > >  security/keys/request_key_auth.c | 2 +-
> > >  4 files changed, 4 insertions(+), 6 deletions(-)
> > > 
> > > diff --git a/security/keys/keyring.c b/security/keys/keyring.c
> > > index 41bcf57e96f21..99a55145ddcd2 100644
> > > --- a/security/keys/keyring.c
> > > +++ b/security/keys/keyring.c
> > > @@ -661,9 +661,6 @@ static bool search_nested_keyrings(struct key 
> > > *keyring,
> > >   BUG_ON((ctx->flags & STATE_CHECKS) == 0 ||
> > >  (ctx->flags & STATE_CHECKS) == STATE_CHECKS);
> > >  
> > > - if (ctx->index_key.description)
> > > - ctx->index_key.desc_len = strlen(ctx->index_key.description);
> > > -
> > >   /* Check to see if this top-level keyring is what we are looking for
> > >* and whether it is valid or not.
> > >*/
> > > @@ -914,6 +911,7 @@ key_ref_t keyring_search(key_ref_t keyring,
> > >   struct keyring_search_context ctx = {
> > >   .index_key.type = type,
> > >   .index_key.description  = description,
> > > + .index_key.desc_len = strlen(description),
> > >   .cred   = current_cred(),
> > >   .match_data.cmp = key_default_cmp,
> > >   .match_data.raw_data= description,
> > > diff --git a/security/keys/proc.c b/security/keys/proc.c
> > > index 5af2934965d80..d38be9db2cc07 100644
> > > --- a/security/keys/proc.c
> > > +++ b/security/keys/proc.c
> > > @@ -166,8 +166,7 @@ static int proc_keys_show(struct seq_file *m, void *v)
> > >   int rc;
> > >  
> > >   struct keyring_search_context ctx = {
> > > - .index_key.type = key->type,
> > > - .index_key.description  = key->description,
> > > + .index_key  = key->index_key,
> > >   .cred   = m->file->f_cred,
> > >   .match_data.cmp = lookup_user_key_possessed,
> > >   .match_data.raw_data= key,
> > > diff --git a/security/keys/request_key.c b/security/keys/request_key.c
> > > index 114f7408feee6..7385536986497 100644
> > > --- a/security/keys/request_key.c
> > > +++ b/security/keys/request_key.c
> > > @@ -545,6 +545,7 @@ struct key *request_key_and_link(struct key_type 
> > > *type,
> > >   struct keyring_search_context ctx = {
> > >   .index_key.type = type,
> > >   .index_key.description  = description,
> > > + .index_key.desc_len = strlen(description),
> > >   .cred   = current_cred(),
> > >   .match_data.cmp = key_default_cmp,
> > >   .match_data.raw_data= description,
> > > diff --git a/security/keys/request_key_auth.c 
> > > b/security/keys/request_key_auth.c
> > > index 424e1d90412ea..6797843154f03 100644
> > > --- a/security/keys/request_key_auth.c
> > > +++ b/security/keys/request_key_auth.c
> > > @@ -246,7 +246,7 @@ struct key 
> > > *key_get_instantiation_authkey(key_serial_t target_id)
> > >   struct key *authkey;
> > >   key_ref_t authkey_ref;
> > >  
> > > - sprintf(description, "%x", target_id);
> > > + ctx.index_key.desc_len = sprintf(description, "%x", target_id);
> > >  
> > >   authkey_ref = search_process_keyrings();
> > >  
> > > 

Re: [PATCH v2] KEYS: always initialize keyring_index_key::desc_len

2019-01-10 Thread Eric Biggers
On Wed, Nov 28, 2018 at 03:19:41PM -0800, Eric Biggers wrote:
> On Fri, Nov 02, 2018 at 06:58:54PM -0700, Eric Biggers wrote:
> > From: Eric Biggers 
> > 
> > syzbot hit the 'BUG_ON(index_key->desc_len == 0);' in __key_link_begin()
> > called from construct_alloc_key() during sys_request_key(), because the
> > length of the key description was never calculated.
> > 
> > The problem is that we rely on ->desc_len being initialized by
> > search_process_keyrings(), specifically by search_nested_keyrings().
> > But, if the process isn't subscribed to any keyrings that never happens.
> > 
> > Fix it by always initializing keyring_index_key::desc_len as soon as the
> > description is set, like we already do in some places.
> > 
> > The following program reproduces the BUG_ON() when it's run as root and
> > no session keyring has been installed.  If it doesn't work, try removing
> > pam_keyinit.so from /etc/pam.d/login and rebooting.
> > 
> > #include 
> > #include 
> > #include 
> > 
> > int main(void)
> > {
> > int id = add_key("keyring", "syz", NULL, 0, 
> > KEY_SPEC_USER_KEYRING);
> > 
> > keyctl_setperm(id, KEY_OTH_WRITE);
> > setreuid(5000, 5000);
> > request_key("user", "desc", "", id);
> > }
> > 
> > Reported-by: syzbot+ec24e95ea483de0a2...@syzkaller.appspotmail.com
> > Fixes: b2a4df200d57 ("KEYS: Expand the capacity of a keyring")
> > Cc:  # v3.13+
> > Signed-off-by: Eric Biggers 
> > ---
> > 
> > v2: In proc_keys_show(), assign index_key directly
> > 
> >  security/keys/keyring.c  | 4 +---
> >  security/keys/proc.c | 3 +--
> >  security/keys/request_key.c  | 1 +
> >  security/keys/request_key_auth.c | 2 +-
> >  4 files changed, 4 insertions(+), 6 deletions(-)
> > 
> > diff --git a/security/keys/keyring.c b/security/keys/keyring.c
> > index 41bcf57e96f21..99a55145ddcd2 100644
> > --- a/security/keys/keyring.c
> > +++ b/security/keys/keyring.c
> > @@ -661,9 +661,6 @@ static bool search_nested_keyrings(struct key *keyring,
> > BUG_ON((ctx->flags & STATE_CHECKS) == 0 ||
> >(ctx->flags & STATE_CHECKS) == STATE_CHECKS);
> >  
> > -   if (ctx->index_key.description)
> > -   ctx->index_key.desc_len = strlen(ctx->index_key.description);
> > -
> > /* Check to see if this top-level keyring is what we are looking for
> >  * and whether it is valid or not.
> >  */
> > @@ -914,6 +911,7 @@ key_ref_t keyring_search(key_ref_t keyring,
> > struct keyring_search_context ctx = {
> > .index_key.type = type,
> > .index_key.description  = description,
> > +   .index_key.desc_len = strlen(description),
> > .cred   = current_cred(),
> > .match_data.cmp = key_default_cmp,
> > .match_data.raw_data= description,
> > diff --git a/security/keys/proc.c b/security/keys/proc.c
> > index 5af2934965d80..d38be9db2cc07 100644
> > --- a/security/keys/proc.c
> > +++ b/security/keys/proc.c
> > @@ -166,8 +166,7 @@ static int proc_keys_show(struct seq_file *m, void *v)
> > int rc;
> >  
> > struct keyring_search_context ctx = {
> > -   .index_key.type = key->type,
> > -   .index_key.description  = key->description,
> > +   .index_key  = key->index_key,
> > .cred   = m->file->f_cred,
> > .match_data.cmp = lookup_user_key_possessed,
> > .match_data.raw_data= key,
> > diff --git a/security/keys/request_key.c b/security/keys/request_key.c
> > index 114f7408feee6..7385536986497 100644
> > --- a/security/keys/request_key.c
> > +++ b/security/keys/request_key.c
> > @@ -545,6 +545,7 @@ struct key *request_key_and_link(struct key_type *type,
> > struct keyring_search_context ctx = {
> > .index_key.type = type,
> > .index_key.description  = description,
> > +   .index_key.desc_len = strlen(description),
> > .cred   = current_cred(),
> > .match_data.cmp = key_default_cmp,
> > .match_data.raw_data= description,
> > diff --git a/security/keys/request_key_auth.c 
> > b/security/keys/request_key_auth.c
> > index 424e1d90412ea..6797843154f03 100644
> > --- a/security/keys/request_key_auth.c
> > +++ b/security/keys/request_key_auth.c
> > @@ -246,7 +246,7 @@ struct key *key_get_instantiation_authkey(key_serial_t 
> > target_id)
> > struct key *authkey;
> > key_ref_t authkey_ref;
> >  
> > -   sprintf(description, "%x", target_id);
> > +   ctx.index_key.desc_len = sprintf(description, "%x", target_id);
> >  
> > authkey_ref = search_process_keyrings();
> >  
> > -- 
> > 2.19.1
> > 
> 
> Ping.  David, are you planning to apply this?
> 
> - Eric
> 
> -- 
> You received this message because you are subscribed to the Google Groups 
> "syzkaller-bugs" group.
> To unsubscribe from this group 

Re: [PATCH v2] KEYS: always initialize keyring_index_key::desc_len

2018-12-06 Thread Eric Biggers
On Wed, Nov 28, 2018 at 03:19:41PM -0800, Eric Biggers wrote:
> On Fri, Nov 02, 2018 at 06:58:54PM -0700, Eric Biggers wrote:
> > From: Eric Biggers 
> > 
> > syzbot hit the 'BUG_ON(index_key->desc_len == 0);' in __key_link_begin()
> > called from construct_alloc_key() during sys_request_key(), because the
> > length of the key description was never calculated.
> > 
> > The problem is that we rely on ->desc_len being initialized by
> > search_process_keyrings(), specifically by search_nested_keyrings().
> > But, if the process isn't subscribed to any keyrings that never happens.
> > 
> > Fix it by always initializing keyring_index_key::desc_len as soon as the
> > description is set, like we already do in some places.
> > 
> > The following program reproduces the BUG_ON() when it's run as root and
> > no session keyring has been installed.  If it doesn't work, try removing
> > pam_keyinit.so from /etc/pam.d/login and rebooting.
> > 
> > #include 
> > #include 
> > #include 
> > 
> > int main(void)
> > {
> > int id = add_key("keyring", "syz", NULL, 0, 
> > KEY_SPEC_USER_KEYRING);
> > 
> > keyctl_setperm(id, KEY_OTH_WRITE);
> > setreuid(5000, 5000);
> > request_key("user", "desc", "", id);
> > }
> > 
> > Reported-by: syzbot+ec24e95ea483de0a2...@syzkaller.appspotmail.com
> > Fixes: b2a4df200d57 ("KEYS: Expand the capacity of a keyring")
> > Cc:  # v3.13+
> > Signed-off-by: Eric Biggers 
> > ---
> > 
> > v2: In proc_keys_show(), assign index_key directly
> > 
> >  security/keys/keyring.c  | 4 +---
> >  security/keys/proc.c | 3 +--
> >  security/keys/request_key.c  | 1 +
> >  security/keys/request_key_auth.c | 2 +-
> >  4 files changed, 4 insertions(+), 6 deletions(-)
> > 
> > diff --git a/security/keys/keyring.c b/security/keys/keyring.c
> > index 41bcf57e96f21..99a55145ddcd2 100644
> > --- a/security/keys/keyring.c
> > +++ b/security/keys/keyring.c
> > @@ -661,9 +661,6 @@ static bool search_nested_keyrings(struct key *keyring,
> > BUG_ON((ctx->flags & STATE_CHECKS) == 0 ||
> >(ctx->flags & STATE_CHECKS) == STATE_CHECKS);
> >  
> > -   if (ctx->index_key.description)
> > -   ctx->index_key.desc_len = strlen(ctx->index_key.description);
> > -
> > /* Check to see if this top-level keyring is what we are looking for
> >  * and whether it is valid or not.
> >  */
> > @@ -914,6 +911,7 @@ key_ref_t keyring_search(key_ref_t keyring,
> > struct keyring_search_context ctx = {
> > .index_key.type = type,
> > .index_key.description  = description,
> > +   .index_key.desc_len = strlen(description),
> > .cred   = current_cred(),
> > .match_data.cmp = key_default_cmp,
> > .match_data.raw_data= description,
> > diff --git a/security/keys/proc.c b/security/keys/proc.c
> > index 5af2934965d80..d38be9db2cc07 100644
> > --- a/security/keys/proc.c
> > +++ b/security/keys/proc.c
> > @@ -166,8 +166,7 @@ static int proc_keys_show(struct seq_file *m, void *v)
> > int rc;
> >  
> > struct keyring_search_context ctx = {
> > -   .index_key.type = key->type,
> > -   .index_key.description  = key->description,
> > +   .index_key  = key->index_key,
> > .cred   = m->file->f_cred,
> > .match_data.cmp = lookup_user_key_possessed,
> > .match_data.raw_data= key,
> > diff --git a/security/keys/request_key.c b/security/keys/request_key.c
> > index 114f7408feee6..7385536986497 100644
> > --- a/security/keys/request_key.c
> > +++ b/security/keys/request_key.c
> > @@ -545,6 +545,7 @@ struct key *request_key_and_link(struct key_type *type,
> > struct keyring_search_context ctx = {
> > .index_key.type = type,
> > .index_key.description  = description,
> > +   .index_key.desc_len = strlen(description),
> > .cred   = current_cred(),
> > .match_data.cmp = key_default_cmp,
> > .match_data.raw_data= description,
> > diff --git a/security/keys/request_key_auth.c 
> > b/security/keys/request_key_auth.c
> > index 424e1d90412ea..6797843154f03 100644
> > --- a/security/keys/request_key_auth.c
> > +++ b/security/keys/request_key_auth.c
> > @@ -246,7 +246,7 @@ struct key *key_get_instantiation_authkey(key_serial_t 
> > target_id)
> > struct key *authkey;
> > key_ref_t authkey_ref;
> >  
> > -   sprintf(description, "%x", target_id);
> > +   ctx.index_key.desc_len = sprintf(description, "%x", target_id);
> >  
> > authkey_ref = search_process_keyrings();
> >  
> > -- 
> > 2.19.1
> > 
> 
> Ping.  David, are you planning to apply this?
> 
> - Eric
> 

Ping.


Re: [PATCH v2] KEYS: always initialize keyring_index_key::desc_len

2018-12-06 Thread Eric Biggers
On Wed, Nov 28, 2018 at 03:19:41PM -0800, Eric Biggers wrote:
> On Fri, Nov 02, 2018 at 06:58:54PM -0700, Eric Biggers wrote:
> > From: Eric Biggers 
> > 
> > syzbot hit the 'BUG_ON(index_key->desc_len == 0);' in __key_link_begin()
> > called from construct_alloc_key() during sys_request_key(), because the
> > length of the key description was never calculated.
> > 
> > The problem is that we rely on ->desc_len being initialized by
> > search_process_keyrings(), specifically by search_nested_keyrings().
> > But, if the process isn't subscribed to any keyrings that never happens.
> > 
> > Fix it by always initializing keyring_index_key::desc_len as soon as the
> > description is set, like we already do in some places.
> > 
> > The following program reproduces the BUG_ON() when it's run as root and
> > no session keyring has been installed.  If it doesn't work, try removing
> > pam_keyinit.so from /etc/pam.d/login and rebooting.
> > 
> > #include 
> > #include 
> > #include 
> > 
> > int main(void)
> > {
> > int id = add_key("keyring", "syz", NULL, 0, 
> > KEY_SPEC_USER_KEYRING);
> > 
> > keyctl_setperm(id, KEY_OTH_WRITE);
> > setreuid(5000, 5000);
> > request_key("user", "desc", "", id);
> > }
> > 
> > Reported-by: syzbot+ec24e95ea483de0a2...@syzkaller.appspotmail.com
> > Fixes: b2a4df200d57 ("KEYS: Expand the capacity of a keyring")
> > Cc:  # v3.13+
> > Signed-off-by: Eric Biggers 
> > ---
> > 
> > v2: In proc_keys_show(), assign index_key directly
> > 
> >  security/keys/keyring.c  | 4 +---
> >  security/keys/proc.c | 3 +--
> >  security/keys/request_key.c  | 1 +
> >  security/keys/request_key_auth.c | 2 +-
> >  4 files changed, 4 insertions(+), 6 deletions(-)
> > 
> > diff --git a/security/keys/keyring.c b/security/keys/keyring.c
> > index 41bcf57e96f21..99a55145ddcd2 100644
> > --- a/security/keys/keyring.c
> > +++ b/security/keys/keyring.c
> > @@ -661,9 +661,6 @@ static bool search_nested_keyrings(struct key *keyring,
> > BUG_ON((ctx->flags & STATE_CHECKS) == 0 ||
> >(ctx->flags & STATE_CHECKS) == STATE_CHECKS);
> >  
> > -   if (ctx->index_key.description)
> > -   ctx->index_key.desc_len = strlen(ctx->index_key.description);
> > -
> > /* Check to see if this top-level keyring is what we are looking for
> >  * and whether it is valid or not.
> >  */
> > @@ -914,6 +911,7 @@ key_ref_t keyring_search(key_ref_t keyring,
> > struct keyring_search_context ctx = {
> > .index_key.type = type,
> > .index_key.description  = description,
> > +   .index_key.desc_len = strlen(description),
> > .cred   = current_cred(),
> > .match_data.cmp = key_default_cmp,
> > .match_data.raw_data= description,
> > diff --git a/security/keys/proc.c b/security/keys/proc.c
> > index 5af2934965d80..d38be9db2cc07 100644
> > --- a/security/keys/proc.c
> > +++ b/security/keys/proc.c
> > @@ -166,8 +166,7 @@ static int proc_keys_show(struct seq_file *m, void *v)
> > int rc;
> >  
> > struct keyring_search_context ctx = {
> > -   .index_key.type = key->type,
> > -   .index_key.description  = key->description,
> > +   .index_key  = key->index_key,
> > .cred   = m->file->f_cred,
> > .match_data.cmp = lookup_user_key_possessed,
> > .match_data.raw_data= key,
> > diff --git a/security/keys/request_key.c b/security/keys/request_key.c
> > index 114f7408feee6..7385536986497 100644
> > --- a/security/keys/request_key.c
> > +++ b/security/keys/request_key.c
> > @@ -545,6 +545,7 @@ struct key *request_key_and_link(struct key_type *type,
> > struct keyring_search_context ctx = {
> > .index_key.type = type,
> > .index_key.description  = description,
> > +   .index_key.desc_len = strlen(description),
> > .cred   = current_cred(),
> > .match_data.cmp = key_default_cmp,
> > .match_data.raw_data= description,
> > diff --git a/security/keys/request_key_auth.c 
> > b/security/keys/request_key_auth.c
> > index 424e1d90412ea..6797843154f03 100644
> > --- a/security/keys/request_key_auth.c
> > +++ b/security/keys/request_key_auth.c
> > @@ -246,7 +246,7 @@ struct key *key_get_instantiation_authkey(key_serial_t 
> > target_id)
> > struct key *authkey;
> > key_ref_t authkey_ref;
> >  
> > -   sprintf(description, "%x", target_id);
> > +   ctx.index_key.desc_len = sprintf(description, "%x", target_id);
> >  
> > authkey_ref = search_process_keyrings();
> >  
> > -- 
> > 2.19.1
> > 
> 
> Ping.  David, are you planning to apply this?
> 
> - Eric
> 

Ping.


Re: [PATCH v2] KEYS: always initialize keyring_index_key::desc_len

2018-11-28 Thread Eric Biggers
On Fri, Nov 02, 2018 at 06:58:54PM -0700, Eric Biggers wrote:
> From: Eric Biggers 
> 
> syzbot hit the 'BUG_ON(index_key->desc_len == 0);' in __key_link_begin()
> called from construct_alloc_key() during sys_request_key(), because the
> length of the key description was never calculated.
> 
> The problem is that we rely on ->desc_len being initialized by
> search_process_keyrings(), specifically by search_nested_keyrings().
> But, if the process isn't subscribed to any keyrings that never happens.
> 
> Fix it by always initializing keyring_index_key::desc_len as soon as the
> description is set, like we already do in some places.
> 
> The following program reproduces the BUG_ON() when it's run as root and
> no session keyring has been installed.  If it doesn't work, try removing
> pam_keyinit.so from /etc/pam.d/login and rebooting.
> 
> #include 
> #include 
> #include 
> 
> int main(void)
> {
> int id = add_key("keyring", "syz", NULL, 0, 
> KEY_SPEC_USER_KEYRING);
> 
> keyctl_setperm(id, KEY_OTH_WRITE);
> setreuid(5000, 5000);
> request_key("user", "desc", "", id);
> }
> 
> Reported-by: syzbot+ec24e95ea483de0a2...@syzkaller.appspotmail.com
> Fixes: b2a4df200d57 ("KEYS: Expand the capacity of a keyring")
> Cc:  # v3.13+
> Signed-off-by: Eric Biggers 
> ---
> 
> v2: In proc_keys_show(), assign index_key directly
> 
>  security/keys/keyring.c  | 4 +---
>  security/keys/proc.c | 3 +--
>  security/keys/request_key.c  | 1 +
>  security/keys/request_key_auth.c | 2 +-
>  4 files changed, 4 insertions(+), 6 deletions(-)
> 
> diff --git a/security/keys/keyring.c b/security/keys/keyring.c
> index 41bcf57e96f21..99a55145ddcd2 100644
> --- a/security/keys/keyring.c
> +++ b/security/keys/keyring.c
> @@ -661,9 +661,6 @@ static bool search_nested_keyrings(struct key *keyring,
>   BUG_ON((ctx->flags & STATE_CHECKS) == 0 ||
>  (ctx->flags & STATE_CHECKS) == STATE_CHECKS);
>  
> - if (ctx->index_key.description)
> - ctx->index_key.desc_len = strlen(ctx->index_key.description);
> -
>   /* Check to see if this top-level keyring is what we are looking for
>* and whether it is valid or not.
>*/
> @@ -914,6 +911,7 @@ key_ref_t keyring_search(key_ref_t keyring,
>   struct keyring_search_context ctx = {
>   .index_key.type = type,
>   .index_key.description  = description,
> + .index_key.desc_len = strlen(description),
>   .cred   = current_cred(),
>   .match_data.cmp = key_default_cmp,
>   .match_data.raw_data= description,
> diff --git a/security/keys/proc.c b/security/keys/proc.c
> index 5af2934965d80..d38be9db2cc07 100644
> --- a/security/keys/proc.c
> +++ b/security/keys/proc.c
> @@ -166,8 +166,7 @@ static int proc_keys_show(struct seq_file *m, void *v)
>   int rc;
>  
>   struct keyring_search_context ctx = {
> - .index_key.type = key->type,
> - .index_key.description  = key->description,
> + .index_key  = key->index_key,
>   .cred   = m->file->f_cred,
>   .match_data.cmp = lookup_user_key_possessed,
>   .match_data.raw_data= key,
> diff --git a/security/keys/request_key.c b/security/keys/request_key.c
> index 114f7408feee6..7385536986497 100644
> --- a/security/keys/request_key.c
> +++ b/security/keys/request_key.c
> @@ -545,6 +545,7 @@ struct key *request_key_and_link(struct key_type *type,
>   struct keyring_search_context ctx = {
>   .index_key.type = type,
>   .index_key.description  = description,
> + .index_key.desc_len = strlen(description),
>   .cred   = current_cred(),
>   .match_data.cmp = key_default_cmp,
>   .match_data.raw_data= description,
> diff --git a/security/keys/request_key_auth.c 
> b/security/keys/request_key_auth.c
> index 424e1d90412ea..6797843154f03 100644
> --- a/security/keys/request_key_auth.c
> +++ b/security/keys/request_key_auth.c
> @@ -246,7 +246,7 @@ struct key *key_get_instantiation_authkey(key_serial_t 
> target_id)
>   struct key *authkey;
>   key_ref_t authkey_ref;
>  
> - sprintf(description, "%x", target_id);
> + ctx.index_key.desc_len = sprintf(description, "%x", target_id);
>  
>   authkey_ref = search_process_keyrings();
>  
> -- 
> 2.19.1
> 

Ping.  David, are you planning to apply this?

- Eric


Re: [PATCH v2] KEYS: always initialize keyring_index_key::desc_len

2018-11-28 Thread Eric Biggers
On Fri, Nov 02, 2018 at 06:58:54PM -0700, Eric Biggers wrote:
> From: Eric Biggers 
> 
> syzbot hit the 'BUG_ON(index_key->desc_len == 0);' in __key_link_begin()
> called from construct_alloc_key() during sys_request_key(), because the
> length of the key description was never calculated.
> 
> The problem is that we rely on ->desc_len being initialized by
> search_process_keyrings(), specifically by search_nested_keyrings().
> But, if the process isn't subscribed to any keyrings that never happens.
> 
> Fix it by always initializing keyring_index_key::desc_len as soon as the
> description is set, like we already do in some places.
> 
> The following program reproduces the BUG_ON() when it's run as root and
> no session keyring has been installed.  If it doesn't work, try removing
> pam_keyinit.so from /etc/pam.d/login and rebooting.
> 
> #include 
> #include 
> #include 
> 
> int main(void)
> {
> int id = add_key("keyring", "syz", NULL, 0, 
> KEY_SPEC_USER_KEYRING);
> 
> keyctl_setperm(id, KEY_OTH_WRITE);
> setreuid(5000, 5000);
> request_key("user", "desc", "", id);
> }
> 
> Reported-by: syzbot+ec24e95ea483de0a2...@syzkaller.appspotmail.com
> Fixes: b2a4df200d57 ("KEYS: Expand the capacity of a keyring")
> Cc:  # v3.13+
> Signed-off-by: Eric Biggers 
> ---
> 
> v2: In proc_keys_show(), assign index_key directly
> 
>  security/keys/keyring.c  | 4 +---
>  security/keys/proc.c | 3 +--
>  security/keys/request_key.c  | 1 +
>  security/keys/request_key_auth.c | 2 +-
>  4 files changed, 4 insertions(+), 6 deletions(-)
> 
> diff --git a/security/keys/keyring.c b/security/keys/keyring.c
> index 41bcf57e96f21..99a55145ddcd2 100644
> --- a/security/keys/keyring.c
> +++ b/security/keys/keyring.c
> @@ -661,9 +661,6 @@ static bool search_nested_keyrings(struct key *keyring,
>   BUG_ON((ctx->flags & STATE_CHECKS) == 0 ||
>  (ctx->flags & STATE_CHECKS) == STATE_CHECKS);
>  
> - if (ctx->index_key.description)
> - ctx->index_key.desc_len = strlen(ctx->index_key.description);
> -
>   /* Check to see if this top-level keyring is what we are looking for
>* and whether it is valid or not.
>*/
> @@ -914,6 +911,7 @@ key_ref_t keyring_search(key_ref_t keyring,
>   struct keyring_search_context ctx = {
>   .index_key.type = type,
>   .index_key.description  = description,
> + .index_key.desc_len = strlen(description),
>   .cred   = current_cred(),
>   .match_data.cmp = key_default_cmp,
>   .match_data.raw_data= description,
> diff --git a/security/keys/proc.c b/security/keys/proc.c
> index 5af2934965d80..d38be9db2cc07 100644
> --- a/security/keys/proc.c
> +++ b/security/keys/proc.c
> @@ -166,8 +166,7 @@ static int proc_keys_show(struct seq_file *m, void *v)
>   int rc;
>  
>   struct keyring_search_context ctx = {
> - .index_key.type = key->type,
> - .index_key.description  = key->description,
> + .index_key  = key->index_key,
>   .cred   = m->file->f_cred,
>   .match_data.cmp = lookup_user_key_possessed,
>   .match_data.raw_data= key,
> diff --git a/security/keys/request_key.c b/security/keys/request_key.c
> index 114f7408feee6..7385536986497 100644
> --- a/security/keys/request_key.c
> +++ b/security/keys/request_key.c
> @@ -545,6 +545,7 @@ struct key *request_key_and_link(struct key_type *type,
>   struct keyring_search_context ctx = {
>   .index_key.type = type,
>   .index_key.description  = description,
> + .index_key.desc_len = strlen(description),
>   .cred   = current_cred(),
>   .match_data.cmp = key_default_cmp,
>   .match_data.raw_data= description,
> diff --git a/security/keys/request_key_auth.c 
> b/security/keys/request_key_auth.c
> index 424e1d90412ea..6797843154f03 100644
> --- a/security/keys/request_key_auth.c
> +++ b/security/keys/request_key_auth.c
> @@ -246,7 +246,7 @@ struct key *key_get_instantiation_authkey(key_serial_t 
> target_id)
>   struct key *authkey;
>   key_ref_t authkey_ref;
>  
> - sprintf(description, "%x", target_id);
> + ctx.index_key.desc_len = sprintf(description, "%x", target_id);
>  
>   authkey_ref = search_process_keyrings();
>  
> -- 
> 2.19.1
> 

Ping.  David, are you planning to apply this?

- Eric