Message ID | 20200502055945.1008194-1-ebiggers@kernel.org (mailing list archive) |
---|---|
State | Not Applicable |
Delegated to: | Herbert Xu |
Headers | show |
Series | ubifs: fix wrong use of crypto_shash_descsize() | expand |
On Fri, May 01, 2020 at 10:59:45PM -0700, Eric Biggers wrote: > From: Eric Biggers <ebiggers@google.com> > > crypto_shash_descsize() returns the size of the shash_desc context > needed to compute the hash, not the size of the hash itself. > > crypto_shash_digestsize() would be correct, or alternatively using > c->hash_len and c->hmac_desc_len which already store the correct values. > But actually it's simpler to just use stack arrays, so do that instead. > > Fixes: 49525e5eecca ("ubifs: Add helper functions for authentication support") > Fixes: da8ef65f9573 ("ubifs: Authenticate replayed journal") > Cc: <stable@vger.kernel.org> # v4.20+ > Cc: Sascha Hauer <s.hauer@pengutronix.de> > Signed-off-by: Eric Biggers <ebiggers@google.com> Looks better that way, thanks. Acked-by: Sascha Hauer <s.hauer@pengutronix.de> Sascha
On Mon, May 04, 2020 at 09:16:44AM +0200, Sascha Hauer wrote: > On Fri, May 01, 2020 at 10:59:45PM -0700, Eric Biggers wrote: > > From: Eric Biggers <ebiggers@google.com> > > > > crypto_shash_descsize() returns the size of the shash_desc context > > needed to compute the hash, not the size of the hash itself. > > > > crypto_shash_digestsize() would be correct, or alternatively using > > c->hash_len and c->hmac_desc_len which already store the correct values. > > But actually it's simpler to just use stack arrays, so do that instead. > > > > Fixes: 49525e5eecca ("ubifs: Add helper functions for authentication support") > > Fixes: da8ef65f9573 ("ubifs: Authenticate replayed journal") > > Cc: <stable@vger.kernel.org> # v4.20+ > > Cc: Sascha Hauer <s.hauer@pengutronix.de> > > Signed-off-by: Eric Biggers <ebiggers@google.com> > > Looks better that way, thanks. > > Acked-by: Sascha Hauer <s.hauer@pengutronix.de> > Richard, could you take this through the ubifs tree for 5.8? - Eric
----- Ursprüngliche Mail ----- > Von: "Eric Biggers" <ebiggers@kernel.org> > An: "Sascha Hauer" <s.hauer@pengutronix.de>, "richard" <richard@nod.at> > CC: "linux-mtd" <linux-mtd@lists.infradead.org>, "Linux Crypto Mailing List" <linux-crypto@vger.kernel.org>, "stable" > <stable@vger.kernel.org> > Gesendet: Freitag, 15. Mai 2020 21:17:04 > Betreff: Re: [PATCH] ubifs: fix wrong use of crypto_shash_descsize() > On Mon, May 04, 2020 at 09:16:44AM +0200, Sascha Hauer wrote: >> On Fri, May 01, 2020 at 10:59:45PM -0700, Eric Biggers wrote: >> > From: Eric Biggers <ebiggers@google.com> >> > >> > crypto_shash_descsize() returns the size of the shash_desc context >> > needed to compute the hash, not the size of the hash itself. >> > >> > crypto_shash_digestsize() would be correct, or alternatively using >> > c->hash_len and c->hmac_desc_len which already store the correct values. >> > But actually it's simpler to just use stack arrays, so do that instead. >> > >> > Fixes: 49525e5eecca ("ubifs: Add helper functions for authentication support") >> > Fixes: da8ef65f9573 ("ubifs: Authenticate replayed journal") >> > Cc: <stable@vger.kernel.org> # v4.20+ >> > Cc: Sascha Hauer <s.hauer@pengutronix.de> >> > Signed-off-by: Eric Biggers <ebiggers@google.com> >> >> Looks better that way, thanks. >> >> Acked-by: Sascha Hauer <s.hauer@pengutronix.de> >> > > Richard, could you take this through the ubifs tree for 5.8? Sure. I actually will send a PR with various MTD related fixes for 5.7. Thanks, //richard
On Fri, May 15, 2020 at 10:50 PM Richard Weinberger <richard@nod.at> wrote: > > ----- Ursprüngliche Mail ----- > > Von: "Eric Biggers" <ebiggers@kernel.org> > > An: "Sascha Hauer" <s.hauer@pengutronix.de>, "richard" <richard@nod.at> > > CC: "linux-mtd" <linux-mtd@lists.infradead.org>, "Linux Crypto Mailing List" <linux-crypto@vger.kernel.org>, "stable" > > <stable@vger.kernel.org> > > Gesendet: Freitag, 15. Mai 2020 21:17:04 > > Betreff: Re: [PATCH] ubifs: fix wrong use of crypto_shash_descsize() > > > On Mon, May 04, 2020 at 09:16:44AM +0200, Sascha Hauer wrote: > >> On Fri, May 01, 2020 at 10:59:45PM -0700, Eric Biggers wrote: > >> > From: Eric Biggers <ebiggers@google.com> > >> > > >> > crypto_shash_descsize() returns the size of the shash_desc context > >> > needed to compute the hash, not the size of the hash itself. > >> > > >> > crypto_shash_digestsize() would be correct, or alternatively using > >> > c->hash_len and c->hmac_desc_len which already store the correct values. > >> > But actually it's simpler to just use stack arrays, so do that instead. > >> > > >> > Fixes: 49525e5eecca ("ubifs: Add helper functions for authentication support") > >> > Fixes: da8ef65f9573 ("ubifs: Authenticate replayed journal") > >> > Cc: <stable@vger.kernel.org> # v4.20+ > >> > Cc: Sascha Hauer <s.hauer@pengutronix.de> > >> > Signed-off-by: Eric Biggers <ebiggers@google.com> > >> > >> Looks better that way, thanks. > >> > >> Acked-by: Sascha Hauer <s.hauer@pengutronix.de> > >> > > > > Richard, could you take this through the ubifs tree for 5.8? > > Sure. I actually will send a PR with various MTD related fixes > for 5.7. Applied. Thanks for fixing!
diff --git a/fs/ubifs/auth.c b/fs/ubifs/auth.c index 8cdbd53d780ca7..f985a3fbbb36a1 100644 --- a/fs/ubifs/auth.c +++ b/fs/ubifs/auth.c @@ -79,13 +79,9 @@ int ubifs_prepare_auth_node(struct ubifs_info *c, void *node, struct shash_desc *inhash) { struct ubifs_auth_node *auth = node; - u8 *hash; + u8 hash[UBIFS_HASH_ARR_SZ]; int err; - hash = kmalloc(crypto_shash_descsize(c->hash_tfm), GFP_NOFS); - if (!hash) - return -ENOMEM; - { SHASH_DESC_ON_STACK(hash_desc, c->hash_tfm); @@ -94,21 +90,16 @@ int ubifs_prepare_auth_node(struct ubifs_info *c, void *node, err = crypto_shash_final(hash_desc, hash); if (err) - goto out; + return err; } err = ubifs_hash_calc_hmac(c, hash, auth->hmac); if (err) - goto out; + return err; auth->ch.node_type = UBIFS_AUTH_NODE; ubifs_prepare_node(c, auth, ubifs_auth_node_sz(c), 0); - - err = 0; -out: - kfree(hash); - - return err; + return 0; } static struct shash_desc *ubifs_get_desc(const struct ubifs_info *c, diff --git a/fs/ubifs/replay.c b/fs/ubifs/replay.c index b28ac4dfb4070a..01fcf79750472b 100644 --- a/fs/ubifs/replay.c +++ b/fs/ubifs/replay.c @@ -601,18 +601,12 @@ static int authenticate_sleb(struct ubifs_info *c, struct ubifs_scan_leb *sleb, struct ubifs_scan_node *snod; int n_nodes = 0; int err; - u8 *hash, *hmac; + u8 hash[UBIFS_HASH_ARR_SZ]; + u8 hmac[UBIFS_HMAC_ARR_SZ]; if (!ubifs_authenticated(c)) return sleb->nodes_cnt; - hash = kmalloc(crypto_shash_descsize(c->hash_tfm), GFP_NOFS); - hmac = kmalloc(c->hmac_desc_len, GFP_NOFS); - if (!hash || !hmac) { - err = -ENOMEM; - goto out; - } - list_for_each_entry(snod, &sleb->nodes, list) { n_nodes++; @@ -662,9 +656,6 @@ static int authenticate_sleb(struct ubifs_info *c, struct ubifs_scan_leb *sleb, err = 0; } out: - kfree(hash); - kfree(hmac); - return err ? err : n_nodes - n_not_auth; }