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authorEnji Cooper <ngie@FreeBSD.org>2017-05-23 07:26:45 +0000
committerEnji Cooper <ngie@FreeBSD.org>2017-05-23 07:26:45 +0000
commitbb09af5f5828ecdcaa5656f05493e31479483f86 (patch)
treed1375460564065284e7c6c43a964a25bba63c274 /lib/libc/sys/_umtx_op.2
parent114e38325ea2ede41db998499e7f961545258e9b (diff)
downloadsrc-bb09af5f5828ecdcaa5656f05493e31479483f86.tar.gz
src-bb09af5f5828ecdcaa5656f05493e31479483f86.zip
_umtx_op(2): fix minor manlint issues
- Sort .Xr entries in SEE ALSO section. - Sort SEE ALSO and STANDARDS sections properly, in terms of the entire document. Reported by: make manlint MFC after: 2 weeks Sponsored by: Dell EMC Isilon
Notes
Notes: svn path=/head/; revision=318715
Diffstat (limited to 'lib/libc/sys/_umtx_op.2')
-rw-r--r--lib/libc/sys/_umtx_op.246
1 files changed, 23 insertions, 23 deletions
diff --git a/lib/libc/sys/_umtx_op.2 b/lib/libc/sys/_umtx_op.2
index 63509991ad24..4682b3426cf8 100644
--- a/lib/libc/sys/_umtx_op.2
+++ b/lib/libc/sys/_umtx_op.2
@@ -28,7 +28,7 @@
.\"
.\" $FreeBSD$
.\"
-.Dd May 29, 2016
+.Dd May 23, 2017
.Dt _UMTX_OP 2
.Os
.Sh NAME
@@ -1382,32 +1382,11 @@ Mutex lock requests without timeout specified are restartable.
The error is not returned to userspace code since restart
is handled by usual adjustment of the instruction counter.
.El
-.Sh BUGS
-A window between a unlocking robust mutex and resetting the pointer in the
-.Dv robust_inact_offset
-member of the registered
-.Vt struct umtx_robust_lists_params
-allows another thread to destroy the mutex, thus making the kernel inspect
-freed or reused memory.
-The
-.Li libthr
-implementation is only vulnerable to this race when operating on
-a shared mutex.
-A possible fix for the current implementation is to strengthen the checks
-for shared mutexes before terminating them, in particular, verifying
-that the mutex memory is mapped from a shared memory object allocated
-by the
-.Dv UMTX_OP_SHM
-request.
-This is not done because it is believed that the race is adequately
-covered by other consistency checks, while adding the check would
-prevent alternative implementations of
-.Li libpthread .
.Sh SEE ALSO
.Xr clock_gettime 2 ,
.Xr mmap 2 ,
-.Xr shm_open 2 ,
.Xr setrlimit 2 ,
+.Xr shm_open 2 ,
.Xr sigaction 2 ,
.Xr thr_exit 2 ,
.Xr thr_kill 2 ,
@@ -1425,3 +1404,24 @@ to implement
.St -p1003.1-2001
.Xr pthread 3
functionality.
+.Sh BUGS
+A window between a unlocking robust mutex and resetting the pointer in the
+.Dv robust_inact_offset
+member of the registered
+.Vt struct umtx_robust_lists_params
+allows another thread to destroy the mutex, thus making the kernel inspect
+freed or reused memory.
+The
+.Li libthr
+implementation is only vulnerable to this race when operating on
+a shared mutex.
+A possible fix for the current implementation is to strengthen the checks
+for shared mutexes before terminating them, in particular, verifying
+that the mutex memory is mapped from a shared memory object allocated
+by the
+.Dv UMTX_OP_SHM
+request.
+This is not done because it is believed that the race is adequately
+covered by other consistency checks, while adding the check would
+prevent alternative implementations of
+.Li libpthread .