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pgsql: Don't test already-referenced pointer for nullness
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* pgsql: Don't test already-referenced pointer for nullness
@ 2024-01-16 11:30  Alvaro Herrera <alvherre@alvh.no-ip.org>
  0 siblings, 0 replies; 4+ messages in thread

From: Alvaro Herrera @ 2024-01-16 11:30 UTC (permalink / raw)
  To: pgsql-committers@lists.postgresql.org

Don't test already-referenced pointer for nullness

Commit b8ba7344e9eb added in PQgetResult a derefence to a pointer
returned by pqPrepareAsyncResult(), before some other code that was
already testing that pointer for nullness.  But since commit
618c16707a6d (in Postgres 15), pqPrepareAsyncResult() doesn't ever
return NULL (a statically-allocated result is returned if OOM).  So in
branches 15 and up, we can remove the redundant pointer check with no
harm done.

However, in branch 14, pqPrepareAsyncResult() can indeed return NULL if
it runs out of memory.  Fix things there by adding a null pointer check
before dereferencing the pointer.  This should hint Coverity that the
preexisting check is not redundant but necessary.

Backpatch to 14, like b8ba7344e9eb.

Per Coverity.

Branch
------
REL_16_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/39aab11085177e4026cec6065a78a425c44e23e3

Modified Files
--------------
src/interfaces/libpq/fe-exec.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)



^ permalink  raw  reply  [nested|flat] 4+ messages in thread

* pgsql: Don't test already-referenced pointer for nullness
@ 2024-01-16 11:30  Alvaro Herrera <alvherre@alvh.no-ip.org>
  0 siblings, 0 replies; 4+ messages in thread

From: Alvaro Herrera @ 2024-01-16 11:30 UTC (permalink / raw)
  To: pgsql-committers@lists.postgresql.org

Don't test already-referenced pointer for nullness

Commit b8ba7344e9eb added in PQgetResult a derefence to a pointer
returned by pqPrepareAsyncResult(), before some other code that was
already testing that pointer for nullness.  But since commit
618c16707a6d (in Postgres 15), pqPrepareAsyncResult() doesn't ever
return NULL (a statically-allocated result is returned if OOM).  So in
branches 15 and up, we can remove the redundant pointer check with no
harm done.

However, in branch 14, pqPrepareAsyncResult() can indeed return NULL if
it runs out of memory.  Fix things there by adding a null pointer check
before dereferencing the pointer.  This should hint Coverity that the
preexisting check is not redundant but necessary.

Backpatch to 14, like b8ba7344e9eb.

Per Coverity.

Branch
------
master

Details
-------
https://git.postgresql.org/pg/commitdiff/c6605c1bdf07e8fc026bf857d37628cbb5746bb8

Modified Files
--------------
src/interfaces/libpq/fe-exec.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)



^ permalink  raw  reply  [nested|flat] 4+ messages in thread

* pgsql: Don't test already-referenced pointer for nullness
@ 2024-01-16 11:30  Alvaro Herrera <alvherre@alvh.no-ip.org>
  0 siblings, 0 replies; 4+ messages in thread

From: Alvaro Herrera @ 2024-01-16 11:30 UTC (permalink / raw)
  To: pgsql-committers@lists.postgresql.org

Don't test already-referenced pointer for nullness

Commit b8ba7344e9eb added in PQgetResult a derefence to a pointer
returned by pqPrepareAsyncResult(), before some other code that was
already testing that pointer for nullness.  But since commit
618c16707a6d (in Postgres 15), pqPrepareAsyncResult() doesn't ever
return NULL (a statically-allocated result is returned if OOM).  So in
branches 15 and up, we can remove the redundant pointer check with no
harm done.

However, in branch 14, pqPrepareAsyncResult() can indeed return NULL if
it runs out of memory.  Fix things there by adding a null pointer check
before dereferencing the pointer.  This should hint Coverity that the
preexisting check is not redundant but necessary.

Backpatch to 14, like b8ba7344e9eb.

Per Coverity.

Branch
------
REL_15_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/2b656cbd2f24edb7e2964fa3f71ca253ee9d81d8

Modified Files
--------------
src/interfaces/libpq/fe-exec.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)



^ permalink  raw  reply  [nested|flat] 4+ messages in thread

* pgsql: Don't test already-referenced pointer for nullness
@ 2024-01-16 11:30  Alvaro Herrera <alvherre@alvh.no-ip.org>
  0 siblings, 0 replies; 4+ messages in thread

From: Alvaro Herrera @ 2024-01-16 11:30 UTC (permalink / raw)
  To: pgsql-committers@lists.postgresql.org

Don't test already-referenced pointer for nullness

Commit b8ba7344e9eb added in PQgetResult a derefence to a pointer
returned by pqPrepareAsyncResult(), before some other code that was
already testing that pointer for nullness.  But since commit
618c16707a6d (in Postgres 15), pqPrepareAsyncResult() doesn't ever
return NULL (a statically-allocated result is returned if OOM).  So in
branches 15 and up, we can remove the redundant pointer check with no
harm done.

However, in branch 14, pqPrepareAsyncResult() can indeed return NULL if
it runs out of memory.  Fix things there by adding a null pointer check
before dereferencing the pointer.  This should hint Coverity that the
preexisting check is not redundant but necessary.

Backpatch to 14, like b8ba7344e9eb.

Per Coverity.

Branch
------
REL_14_STABLE

Details
-------
https://git.postgresql.org/pg/commitdiff/7a7c8c98a610418ed0118e22a1793bf27e55783a

Modified Files
--------------
src/interfaces/libpq/fe-exec.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)



^ permalink  raw  reply  [nested|flat] 4+ messages in thread


end of thread, other threads:[~2024-01-16 11:30 UTC | newest]

Thread overview: 4+ messages (download: mbox mbox.gz follow: Atom feed)
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2024-01-16 11:30 pgsql: Don't test already-referenced pointer for nullness Alvaro Herrera <alvherre@alvh.no-ip.org>
2024-01-16 11:30 pgsql: Don't test already-referenced pointer for nullness Alvaro Herrera <alvherre@alvh.no-ip.org>
2024-01-16 11:30 pgsql: Don't test already-referenced pointer for nullness Alvaro Herrera <alvherre@alvh.no-ip.org>
2024-01-16 11:30 pgsql: Don't test already-referenced pointer for nullness Alvaro Herrera <alvherre@alvh.no-ip.org>

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