Am Sonntag, 8. April 2018, 17:41:17 CEST schrieb Dmitry Vyukov: Hi Dmitry, > > Hi, > > Here is config and kernel commit: > https://groups.google.com/d/msg/syzkaller-bugs/PINYyzoaG1s/ntZPOZdcCAAJ > You can also find compiler and image here if necessary: > https://github.com/google/syzkaller/blob/master/docs/syzbot.md > > And note that the program needs to be compiled with -m32. The bugs is > probably not-compat specific, but the program injects fault into a > particular malloc invocation and maybe malloc numbering is affected by > compat path.
I am unable to reproduce the issue. But since you mention that you induce errors, I could see that the unlocking of the DRBG context is too soon. Can you please check whether the attached patch fixes the issue? Thanks ---8<--- In the error code path, the uninstantiation must be guarded by a lock to ensure that the modification of the context is fully atomic. Signed-off-by: Stephan Mueller <smuel...@chronox.de> Reported-by: syzkaller --- crypto/drbg.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/crypto/drbg.c b/crypto/drbg.c index 4faa2781c964..68c1949a253f 100644 --- a/crypto/drbg.c +++ b/crypto/drbg.c @@ -1510,8 +1510,8 @@ static int drbg_instantiate(struct drbg_state *drbg, struct drbg_string *pers, return ret; free_everything: - mutex_unlock(&drbg->drbg_mutex); drbg_uninstantiate(drbg); + mutex_unlock(&drbg->drbg_mutex); return ret; } -- 2.14.3