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From: Liam Merwick <Liam.Merwick@oracle.com>
To: qemu-devel@nongnu.org
Subject: [Qemu-devel] [PATCH v2 7/8] io: potential unnecessary check in qio_channel_command_new_spawn()
Date: Fri, 31 Aug 2018 17:36:53 +0100	[thread overview]
Message-ID: <1535733414-6812-8-git-send-email-Liam.Merwick@oracle.com> (raw)
In-Reply-To: <1535733414-6812-1-git-send-email-Liam.Merwick@oracle.com>

In qio_channel_command_new_spawn() the 'flags' variable is checked
to see if /dev/null should be used for stdin or stdout; first with
O_RDONLY and then O_WRONLY.  However the second check for O_WRONLY
is only needed if flags != O_RDONLY and therefore should be an
else if statement.

This minor optimization has the added benefit of suppressing a warning
from a static analysis tool (Parfait) which incorrectly reported an
incorrect checking of flags in qio_channel_command_new_spawn() could
result in an uninitialized file descriptor being used. Removing this
noise will help us better find real issues.

Signed-off-by: Liam Merwick <Liam.Merwick@oracle.com>
---
 io/channel-command.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/io/channel-command.c b/io/channel-command.c
index 3e7eb17eff54..82acd3234915 100644
--- a/io/channel-command.c
+++ b/io/channel-command.c
@@ -61,8 +61,7 @@ qio_channel_command_new_spawn(const char *const argv[],
 
     if (flags == O_RDONLY) {
         stdinnull = true;
-    }
-    if (flags == O_WRONLY) {
+    } else if (flags == O_WRONLY) {
         stdoutnull = true;
     }
 
-- 
1.8.3.1

  parent reply	other threads:[~2018-08-31 16:35 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-08-31 16:36 [Qemu-devel] [PATCH v2 0/8] off-by-one and NULL pointer accesses detected by static analysis Liam Merwick
2018-08-31 16:36 ` [Qemu-devel] [PATCH v2 1/8] configure: Provide option to explicitly disable AVX2 Liam Merwick
2018-08-31 16:36 ` [Qemu-devel] [PATCH v2 2/8] job: Fix off-by-one assert checks for JobSTT and JobVerbTable Liam Merwick
2018-08-31 16:36 ` [Qemu-devel] [PATCH v2 3/8] block: Null pointer dereference in blk_root_get_parent_desc() Liam Merwick
2018-08-31 16:36 ` [Qemu-devel] [PATCH v2 4/8] qemu-img: potential Null pointer deref in img_commit() Liam Merwick
2018-08-31 16:36 ` [Qemu-devel] [PATCH v2 5/8] block: Fix potential Null pointer dereferences in vvfat.c Liam Merwick
2018-08-31 16:36 ` [Qemu-devel] [PATCH v2 6/8] block: dump_qlist() may dereference a Null pointer Liam Merwick
2018-08-31 16:47   ` Eric Blake
2018-08-31 16:36 ` Liam Merwick [this message]
2018-08-31 16:48   ` [Qemu-devel] [PATCH v2 7/8] io: potential unnecessary check in qio_channel_command_new_spawn() Eric Blake
2018-08-31 16:36 ` [Qemu-devel] [PATCH v2 8/8] qcow2: Read outside array bounds in qcow2_pre_write_overlap_check() Liam Merwick
2018-08-31 16:53   ` Eric Blake
2018-08-31 18:16     ` Liam Merwick

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