| Message ID | 743fc62b2e8d15c84e234744e3f3f136c467752d.1664442592.git.leonro@nvidia.com (mailing list archive) |
|---|---|
| State | Not Applicable |
| Delegated to: | Netdev Maintainers |
| Headers | show |
| Series | Fix to latest syzkaller bugs in 9p area | expand |
| Context | Check | Description |
|---|---|---|
| netdev/tree_selection | success | Guessing tree name failed - patch did not apply |
Leon Romanovsky wrote on Thu, Sep 29, 2022 at 12:37:56PM +0300: > Make sure that all variables are initialized and released in correct > order. Haven't tried running or compiling, comments out of my head that might be wrong below > > Reported-by: syzbot+de52531662ebb8823b26@syzkaller.appspotmail.com You're adding this report tag but I don't see how you fix that failure. What you need is p9_tag_cleanup(clnt) from p9_client_destroy -- I assume this isn't possible for any fid to be allocated at this point so the fid destroying loop is -probably- optional. I would assume it is needed from p9_client_version failures. > Signed-off-by: Leon Romanovsky <leon@kernel.org> > --- > net/9p/client.c | 37 ++++++++++++------------------------- > 1 file changed, 12 insertions(+), 25 deletions(-) > > diff --git a/net/9p/client.c b/net/9p/client.c > index aaa37b07e30a..8277e33506e7 100644 > --- a/net/9p/client.c > +++ b/net/9p/client.c > @@ -179,7 +179,6 @@ static int parse_opts(char *opts, struct p9_client *clnt) > goto free_and_return; > } > > - v9fs_put_trans(clnt->trans_mod); Pretty sure you'll be "leaking transports" if someone tries to pass trans=foo multiple times; this can't be removed...(continues below)... > clnt->trans_mod = v9fs_get_trans_by_name(s); > if (!clnt->trans_mod) { > pr_info("Could not find request transport: %s\n", > @@ -187,7 +186,7 @@ static int parse_opts(char *opts, struct p9_client *clnt) > ret = -EINVAL; > } > kfree(s); > - break; > + goto free_and_return; ... unless you also break the whole parsing, with this asking for -o trans=virtio,msize=1M will just ignore the msize argument. (or anything else that follows) I appreciate that you're trying to avoid the get_default_trans below, but unless you just remember the last string and try to get it get/put trans is the most straight forward way to go. (Note you just got me to try weird parsing and my old version was double-puting these modules because of the put_trans below in this function echoes with the client destroy. That'd just require removing the put here though (or nulling after put), yet another invariant I had wrongly assumed... Anyway.) > case Opt_legacy: > clnt->proto_version = p9_proto_legacy; > break; > @@ -211,9 +210,14 @@ static int parse_opts(char *opts, struct p9_client *clnt) > } > } > > + clnt->trans_mod = v9fs_get_default_trans(); > + if (!clnt->trans_mod) { > + ret = -EPROTONOSUPPORT; > + p9_debug(P9_DEBUG_ERROR, > + "No transport defined or default transport\n"); > + } > + > free_and_return: > - if (ret) > - v9fs_put_trans(clnt->trans_mod); (oh, and if you parse options after trans= you'll need some sort of escape hatch here...) > kfree(tmp_options); > return ret; > } > @@ -956,19 +960,14 @@ static int p9_client_version(struct p9_client *c) > > struct p9_client *p9_client_create(const char *dev_name, char *options) > { > - int err; > struct p9_client *clnt; > char *client_id; > + int err = 0; > > - err = 0; > - clnt = kmalloc(sizeof(*clnt), GFP_KERNEL); > + clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); > if (!clnt) > return ERR_PTR(-ENOMEM); > > - clnt->trans_mod = NULL; > - clnt->trans = NULL; > - clnt->fcall_cache = NULL; > - > client_id = utsname()->nodename; > memcpy(clnt->name, client_id, strlen(client_id) + 1); > > @@ -980,16 +979,6 @@ struct p9_client *p9_client_create(const char *dev_name, char *options) > if (err < 0) > goto free_client; > > - if (!clnt->trans_mod) > - clnt->trans_mod = v9fs_get_default_trans(); > - > - if (!clnt->trans_mod) { > - err = -EPROTONOSUPPORT; > - p9_debug(P9_DEBUG_ERROR, > - "No transport defined or default transport\n"); > - goto free_client; > - } > - > p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n", > clnt, clnt->trans_mod, clnt->msize, clnt->proto_version); > > @@ -1044,9 +1033,8 @@ void p9_client_destroy(struct p9_client *clnt) > > p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt); > > - if (clnt->trans_mod) > - clnt->trans_mod->close(clnt); > - > + kmem_cache_destroy(clnt->fcall_cache); Pretty sure kmem_cache used to issue a warning when we did that (hence me trying to move it up on allocation) -- at this point there can still be in flight requests we need to finish freeing before we can destroy the cache. > + clnt->trans_mod->close(clnt); > v9fs_put_trans(clnt->trans_mod); > > idr_for_each_entry(&clnt->fids, fid, id) { > @@ -1056,7 +1044,6 @@ void p9_client_destroy(struct p9_client *clnt) > > p9_tag_cleanup(clnt); > > - kmem_cache_destroy(clnt->fcall_cache); > kfree(clnt); > } > EXPORT_SYMBOL(p9_client_destroy); -- Dominique
On Thu, Sep 29, 2022 at 07:29:33PM +0900, Dominique Martinet wrote: > Leon Romanovsky wrote on Thu, Sep 29, 2022 at 12:37:56PM +0300: > > Make sure that all variables are initialized and released in correct > > order. > > Haven't tried running or compiling, comments out of my head that might > be wrong below > > > > > Reported-by: syzbot+de52531662ebb8823b26@syzkaller.appspotmail.com > > You're adding this report tag but I don't see how you fix that failure. > What you need is p9_tag_cleanup(clnt) from p9_client_destroy -- I assume > this isn't possible for any fid to be allocated at this point so the fid > destroying loop is -probably- optional. > > I would assume it is needed from p9_client_version failures. > > > > Signed-off-by: Leon Romanovsky <leon@kernel.org> > > --- > > net/9p/client.c | 37 ++++++++++++------------------------- > > 1 file changed, 12 insertions(+), 25 deletions(-) > > > > diff --git a/net/9p/client.c b/net/9p/client.c > > index aaa37b07e30a..8277e33506e7 100644 > > --- a/net/9p/client.c > > +++ b/net/9p/client.c > > @@ -179,7 +179,6 @@ static int parse_opts(char *opts, struct p9_client *clnt) > > goto free_and_return; > > } > > > > - v9fs_put_trans(clnt->trans_mod); > > Pretty sure you'll be "leaking transports" if someone tries to pass > trans=foo multiple times; this can't be removed...(continues below)... It is pity, you are right. Thanks
On Donnerstag, 29. September 2022 12:53:27 CEST Leon Romanovsky wrote: > On Thu, Sep 29, 2022 at 07:29:33PM +0900, Dominique Martinet wrote: > > Leon Romanovsky wrote on Thu, Sep 29, 2022 at 12:37:56PM +0300: > > > Make sure that all variables are initialized and released in correct > > > order. > > > > Haven't tried running or compiling, comments out of my head that might > > be wrong below > > > > > Reported-by: syzbot+de52531662ebb8823b26@syzkaller.appspotmail.com > > > > You're adding this report tag but I don't see how you fix that failure. > > What you need is p9_tag_cleanup(clnt) from p9_client_destroy -- I assume > > this isn't possible for any fid to be allocated at this point so the fid > > destroying loop is -probably- optional. > > > > I would assume it is needed from p9_client_version failures. > > > > > Signed-off-by: Leon Romanovsky <leon@kernel.org> > > > --- > > > > > > net/9p/client.c | 37 ++++++++++++------------------------- > > > 1 file changed, 12 insertions(+), 25 deletions(-) > > > > > > diff --git a/net/9p/client.c b/net/9p/client.c > > > index aaa37b07e30a..8277e33506e7 100644 > > > --- a/net/9p/client.c > > > +++ b/net/9p/client.c > > > @@ -179,7 +179,6 @@ static int parse_opts(char *opts, struct p9_client > > > *clnt)> > > > > goto free_and_return; > > > > > > } > > > > > > - v9fs_put_trans(clnt->trans_mod); > > > > Pretty sure you'll be "leaking transports" if someone tries to pass > > trans=foo multiple times; this can't be removed...(continues below)... > > It is pity, you are right. > > Thanks Hi Leon, have you planned a v2 on this? Just asking, so that we know whether to go forward. Best regards, Christian Schoenebeck
diff --git a/net/9p/client.c b/net/9p/client.c index aaa37b07e30a..8277e33506e7 100644 --- a/net/9p/client.c +++ b/net/9p/client.c @@ -179,7 +179,6 @@ static int parse_opts(char *opts, struct p9_client *clnt) goto free_and_return; } - v9fs_put_trans(clnt->trans_mod); clnt->trans_mod = v9fs_get_trans_by_name(s); if (!clnt->trans_mod) { pr_info("Could not find request transport: %s\n", @@ -187,7 +186,7 @@ static int parse_opts(char *opts, struct p9_client *clnt) ret = -EINVAL; } kfree(s); - break; + goto free_and_return; case Opt_legacy: clnt->proto_version = p9_proto_legacy; break; @@ -211,9 +210,14 @@ static int parse_opts(char *opts, struct p9_client *clnt) } } + clnt->trans_mod = v9fs_get_default_trans(); + if (!clnt->trans_mod) { + ret = -EPROTONOSUPPORT; + p9_debug(P9_DEBUG_ERROR, + "No transport defined or default transport\n"); + } + free_and_return: - if (ret) - v9fs_put_trans(clnt->trans_mod); kfree(tmp_options); return ret; } @@ -956,19 +960,14 @@ static int p9_client_version(struct p9_client *c) struct p9_client *p9_client_create(const char *dev_name, char *options) { - int err; struct p9_client *clnt; char *client_id; + int err = 0; - err = 0; - clnt = kmalloc(sizeof(*clnt), GFP_KERNEL); + clnt = kzalloc(sizeof(*clnt), GFP_KERNEL); if (!clnt) return ERR_PTR(-ENOMEM); - clnt->trans_mod = NULL; - clnt->trans = NULL; - clnt->fcall_cache = NULL; - client_id = utsname()->nodename; memcpy(clnt->name, client_id, strlen(client_id) + 1); @@ -980,16 +979,6 @@ struct p9_client *p9_client_create(const char *dev_name, char *options) if (err < 0) goto free_client; - if (!clnt->trans_mod) - clnt->trans_mod = v9fs_get_default_trans(); - - if (!clnt->trans_mod) { - err = -EPROTONOSUPPORT; - p9_debug(P9_DEBUG_ERROR, - "No transport defined or default transport\n"); - goto free_client; - } - p9_debug(P9_DEBUG_MUX, "clnt %p trans %p msize %d protocol %d\n", clnt, clnt->trans_mod, clnt->msize, clnt->proto_version); @@ -1044,9 +1033,8 @@ void p9_client_destroy(struct p9_client *clnt) p9_debug(P9_DEBUG_MUX, "clnt %p\n", clnt); - if (clnt->trans_mod) - clnt->trans_mod->close(clnt); - + kmem_cache_destroy(clnt->fcall_cache); + clnt->trans_mod->close(clnt); v9fs_put_trans(clnt->trans_mod); idr_for_each_entry(&clnt->fids, fid, id) { @@ -1056,7 +1044,6 @@ void p9_client_destroy(struct p9_client *clnt) p9_tag_cleanup(clnt); - kmem_cache_destroy(clnt->fcall_cache); kfree(clnt); } EXPORT_SYMBOL(p9_client_destroy);
Make sure that all variables are initialized and released in correct order. Reported-by: syzbot+de52531662ebb8823b26@syzkaller.appspotmail.com Signed-off-by: Leon Romanovsky <leon@kernel.org> --- net/9p/client.c | 37 ++++++++++++------------------------- 1 file changed, 12 insertions(+), 25 deletions(-)