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| author | Svenning Soerensen <sss@secomea.dk> | 2013-08-28 16:35:17 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2013-09-07 22:09:58 -0700 |
| commit | 07245f175c74d7d50663dc6758094c683c07f510 (patch) | |
| tree | 3a9aa74d17e8a5a534d5dee9dc11108335699a3a /ipc | |
| parent | b3772c81e3490f1ddc0547ee479598f3f4221699 (diff) | |
| download | linux-3.10-07245f175c74d7d50663dc6758094c683c07f510.tar.gz linux-3.10-07245f175c74d7d50663dc6758094c683c07f510.tar.bz2 linux-3.10-07245f175c74d7d50663dc6758094c683c07f510.zip | |
IPC: bugfix for msgrcv with msgtyp < 0
commit 368ae537e056acd3f751fa276f48423f06803922 upstream.
According to 'man msgrcv': "If msgtyp is less than 0, the first message of
the lowest type that is less than or equal to the absolute value of msgtyp
shall be received."
Bug: The kernel only returns a message if its type is 1; other messages
with type < abs(msgtype) will never get returned.
Fix: After having traversed the list to find the first message with the
lowest type, we need to actually return that message.
This regression was introduced by commit daaf74cf0867 ("ipc: refactor
msg list search into separate function")
Signed-off-by: Svenning Soerensen <sss@secomea.dk>
Reviewed-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'ipc')
| -rw-r--r-- | ipc/msg.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/ipc/msg.c b/ipc/msg.c index d0c6d967b39..f8fbe2c095c 100644 --- a/ipc/msg.c +++ b/ipc/msg.c @@ -795,7 +795,7 @@ static inline void free_copy(struct msg_msg *copy) static struct msg_msg *find_msg(struct msg_queue *msq, long *msgtyp, int mode) { - struct msg_msg *msg; + struct msg_msg *msg, *found = NULL; long count = 0; list_for_each_entry(msg, &msq->q_messages, m_list) { @@ -804,6 +804,7 @@ static struct msg_msg *find_msg(struct msg_queue *msq, long *msgtyp, int mode) *msgtyp, mode)) { if (mode == SEARCH_LESSEQUAL && msg->m_type != 1) { *msgtyp = msg->m_type - 1; + found = msg; } else if (mode == SEARCH_NUMBER) { if (*msgtyp == count) return msg; @@ -813,7 +814,7 @@ static struct msg_msg *find_msg(struct msg_queue *msq, long *msgtyp, int mode) } } - return ERR_PTR(-EAGAIN); + return found ?: ERR_PTR(-EAGAIN); } |