Re: [HACKERS] Suspicious place in heap_prepare_freeze_tuple()
Masahiko Sawada wrote: > On Thu, Jul 6, 2017 at 1:36 AM, Alvaro Herrera > wrote: > > Teodor Sigaev wrote: > > > >> Playing around freezing tuple I found suspicious piece of code: > >> > >> heap_prepare_freeze_tuple(): > >> ... > >> frz->t_infomask = tuple->t_infomask; > >> ... > >> frz->t_infomask &= ~HEAP_XMAX_BITS; > >> frz->xmax = newxmax; > >> if (flags & FRM_MARK_COMMITTED) > >> frz->t_infomask &= HEAP_XMAX_COMMITTED; > >> > >> Seems, in last line it should be a bitwise OR instead of AND. Now this line > >> cleans all bits in t_infomask which later will be copied directly in tuple. > > > > I think you're right. > > I also think that's right. Should we back-patch it down to 9.3? Of course. I think this could cause data corruption. -- Álvaro Herrerahttps://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] Suspicious place in heap_prepare_freeze_tuple()
On Thu, Jul 6, 2017 at 1:36 AM, Alvaro Herrera wrote: > Teodor Sigaev wrote: > >> Playing around freezing tuple I found suspicious piece of code: >> >> heap_prepare_freeze_tuple(): >> ... >> frz->t_infomask = tuple->t_infomask; >> ... >> frz->t_infomask &= ~HEAP_XMAX_BITS; >> frz->xmax = newxmax; >> if (flags & FRM_MARK_COMMITTED) >> frz->t_infomask &= HEAP_XMAX_COMMITTED; >> >> Seems, in last line it should be a bitwise OR instead of AND. Now this line >> cleans all bits in t_infomask which later will be copied directly in tuple. > > I think you're right. > I also think that's right. Should we back-patch it down to 9.3? Regards, -- Masahiko Sawada NIPPON TELEGRAPH AND TELEPHONE CORPORATION NTT Open Source Software Center -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
Re: [HACKERS] Suspicious place in heap_prepare_freeze_tuple()
Teodor Sigaev wrote: > Playing around freezing tuple I found suspicious piece of code: > > heap_prepare_freeze_tuple(): > ... > frz->t_infomask = tuple->t_infomask; > ... > frz->t_infomask &= ~HEAP_XMAX_BITS; > frz->xmax = newxmax; > if (flags & FRM_MARK_COMMITTED) > frz->t_infomask &= HEAP_XMAX_COMMITTED; > > Seems, in last line it should be a bitwise OR instead of AND. Now this line > cleans all bits in t_infomask which later will be copied directly in tuple. I think you're right. -- Álvaro Herrerahttps://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
