On Wed, 19 Nov 2014, Konstantin Khlebnikov wrote: > On Wed, Nov 19, 2014 at 12:41 PM, Julia Lawall <julia.lawall at lip6.fr> wrote: > >> +// Comments: There are false positives in crypto/ where they are > >> actually freed. > > > > I didn't really understand this comment. I ran the semantic patch and got > > around 10 results, but it wasn't clear to me how to see which were false > > positives. > > I mean false positives in code inside directory crypto/ where this > subsystem lives. > > ./arch/x86/crypto/fpu.c:143:1-6: WARNING: invalid free of > crypto_alloc_* allocated data > ./crypto/algapi.c:846:1-6: WARNING: invalid free of crypto_alloc_* > allocated data > ./crypto/lrw.c:378:1-6: WARNING: invalid free of crypto_alloc_* allocated data > ./crypto/ecb.c:163:1-6: WARNING: invalid free of crypto_alloc_* allocated data > ./crypto/ctr.c:242:1-6: WARNING: invalid free of crypto_alloc_* allocated data > ./crypto/ctr.c:419:1-6: WARNING: invalid free of crypto_alloc_* allocated data > ./crypto/ctr.c:428:1-6: WARNING: invalid free of crypto_alloc_* allocated data > ./crypto/pcbc.c:273:1-6: WARNING: invalid free of crypto_alloc_* allocated data > ./crypto/cts.c:329:1-6: WARNING: invalid free of crypto_alloc_* allocated data > ./crypto/cbc.c:267:1-6: WARNING: invalid free of crypto_alloc_* allocated data > ./crypto/xts.c:340:1-6: WARNING: invalid free of crypto_alloc_* allocated data > > This is kfree calls on error paths in constructors or in destructors > which actually frees memory when crypto_free_* is called. Sorry, but I am not sure to fully understand the issue. Is it actually just the case that crypto_alloc_instance and crypto_alloc_instance2 should not be in the list of allocation functions, because their results should be freed with kfree? julia > > > > > I would suggest to extend the rule a little bit to include information > > about where the allocation call is: > > Not sure if this is necessary. This part of crypto-api is simple. > > > > > /// > > /// Structures allocated by crypto_alloc_* must be freed using crypto_free_*. > > /// This finds freeing them by kfree. > > /// > > // Confidence: Moderate > > // Copyright: (C) 2014 Konstantin Khlebnikov, GPLv2. > > // Comments: There are false positives in crypto/ where they are actually freed. > > // Keywords: crypto, kfree > > // Options: --no-includes --include-headers > > > > virtual org > > virtual report > > virtual context > > > > @r depends on context || org || report@ > > expression x; > > position p1; > > @@ > > > > ( > > x = crypto_alloc_base at p1(...) > > | > > x = crypto_alloc_cipher at p1(...) > > | > > x = crypto_alloc_ablkcipher at p1(...) > > | > > x = crypto_alloc_aead at p1(...) > > | > > x = crypto_alloc_instance at p1(...) > > | > > x = crypto_alloc_instance2 at p1(...) > > | > > x = crypto_alloc_comp at p1(...) > > | > > x = crypto_alloc_pcomp at p1(...) > > | > > x = crypto_alloc_hash at p1(...) > > | > > x = crypto_alloc_ahash at p1(...) > > | > > x = crypto_alloc_shash at p1(...) > > | > > x = crypto_alloc_rng at p1(...) > > ) > > > > @pb@ > > expression r.x; > > position p; > > @@ > > > > * kfree at p(x) > > > > @script:python depends on org@ > > p << pb.p; > > p1 << r.p1; > > @@ > > > > msg="WARNING: invalid free of crypto_alloc_* allocated data" > > coccilib.org.print_todo(p[0], msg) > > coccilib.org.print_link(p1[0], "allocation") > > > > @script:python depends on report@ > > p << pb.p; > > p1 << r.p1; > > @@ > > > > msg="WARNING: invalid free of crypto_alloc_* allocated data, allocated on line %s" % (p1[0].line) > > coccilib.report.print_report(p[0], msg) > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > > the body of a message to majordomo at vger.kernel.org > > More majordomo info at http://vger.kernel.org/majordomo-info.html > > Please read the FAQ at http://www.tux.org/lkml/ >
