Movatterモバイル変換

[0]ホーム
URL:

Skip to content

Navigation Menu

Sign in
Appearance settings

Search code, repositories, users, issues, pull requests...

Provide feedback

We read every piece of feedback, and take your input very seriously.

Saved searches

Use saved searches to filter your results more quickly

 Sign up
Appearance settings

Commita97dfdf

Browse files
committed
Fix Coverity warning about contrib/pgcrypto's mdc_finish().
Coverity points out that mdc_finish returns a pointer to a local buffer(which of course is gone as soon as the function returns), leaving opena risk of misbehaviors possibly as bad as a stack overwrite.In reality, the only possible call site is in process_data_packets()which does not examine the returned pointer at all. So there's nolive bug, but nonetheless the code is confusing and risky. Refactorto avoid the issue by letting process_data_packets() call mdc_finish()directly instead of going through the pullf_read() API.Although this is only cosmetic, it seems good to back-patch so thatthe logic in pgp-decrypt.c stays in sync across all branches.Marko Kreen
1 parent915290e commita97dfdf

File tree

1 file changed

+19
-30
lines changed

1 file changed

+19
-30
lines changed

‎contrib/pgcrypto/pgp-decrypt.c‎

Lines changed: 19 additions & 30 deletions
Original file line numberDiff line numberDiff line change
@@ -351,37 +351,33 @@ mdc_free(void *priv)
351351
}
352352

353353
staticint
354-
mdc_finish(PGP_Context*ctx,PullFilter*src,
355-
intlen,uint8**data_p)
354+
mdc_finish(PGP_Context*ctx,PullFilter*src,intlen)
356355
{
357356
intres;
358357
uint8hash[20];
359-
uint8tmpbuf[22];
358+
uint8tmpbuf[20];
359+
uint8*data;
360360

361-
if (len+1>sizeof(tmpbuf))
361+
/* should not happen */
362+
if (ctx->use_mdcbuf_filter)
362363
returnPXE_BUG;
363364

365+
/* It's SHA1 */
366+
if (len!=20)
367+
returnPXE_PGP_CORRUPT_DATA;
368+
369+
/* mdc_read should not call md_update */
370+
ctx->in_mdc_pkt=1;
371+
364372
/* read data */
365-
res=pullf_read_max(src,len+1,data_p,tmpbuf);
373+
res=pullf_read_max(src,len,&data,tmpbuf);
366374
if (res<0)
367375
returnres;
368376
if (res==0)
369377
{
370-
if (ctx->mdc_checked==0)
371-
{
372-
px_debug("no mdc");
373-
returnPXE_PGP_CORRUPT_DATA;
374-
}
375-
return0;
376-
}
377-
378-
/* safety check */
379-
if (ctx->in_mdc_pkt>1)
380-
{
381-
px_debug("mdc_finish: several times here?");
378+
px_debug("no mdc");
382379
returnPXE_PGP_CORRUPT_DATA;
383380
}
384-
ctx->in_mdc_pkt++;
385381

386382
/* is the packet sane? */
387383
if (res!=20)
@@ -394,7 +390,7 @@ mdc_finish(PGP_Context *ctx, PullFilter *src,
394390
* ok, we got the hash, now check
395391
*/
396392
px_md_finish(ctx->mdc_ctx,hash);
397-
res=memcmp(hash,*data_p,20);
393+
res=memcmp(hash,data,20);
398394
px_memset(hash,0,20);
399395
px_memset(tmpbuf,0,sizeof(tmpbuf));
400396
if (res!=0)
@@ -403,7 +399,7 @@ mdc_finish(PGP_Context *ctx, PullFilter *src,
403399
returnPXE_PGP_CORRUPT_DATA;
404400
}
405401
ctx->mdc_checked=1;
406-
returnlen;
402+
return0;
407403
}
408404

409405
staticint
@@ -414,12 +410,9 @@ mdc_read(void *priv, PullFilter *src, int len,
414410
PGP_Context*ctx=priv;
415411

416412
/* skip this filter? */
417-
if (ctx->use_mdcbuf_filter)
413+
if (ctx->use_mdcbuf_filter||ctx->in_mdc_pkt)
418414
returnpullf_read(src,len,data_p);
419415

420-
if (ctx->in_mdc_pkt)
421-
returnmdc_finish(ctx,src,len,data_p);
422-
423416
res=pullf_read(src,len,data_p);
424417
if (res<0)
425418
returnres;
@@ -878,7 +871,6 @@ process_data_packets(PGP_Context *ctx, MBuf *dst, PullFilter *src,
878871
intgot_data=0;
879872
intgot_mdc=0;
880873
PullFilter*pkt=NULL;
881-
uint8*tmp;
882874

883875
while (1)
884876
{
@@ -937,11 +929,8 @@ process_data_packets(PGP_Context *ctx, MBuf *dst, PullFilter *src,
937929
break;
938930
}
939931

940-
/* notify mdc_filter */
941-
ctx->in_mdc_pkt=1;
942-
943-
res=pullf_read(pkt,8192,&tmp);
944-
if (res>0)
932+
res=mdc_finish(ctx,pkt,len);
933+
if (res >=0)
945934
got_mdc=1;
946935
break;
947936
default:

0 commit comments

Comments
 (0)
[8]ページ先頭
©2009-2025 Movatter.jp