This issue is introduced by commit 0fc8909, the virBitmapIsSet() needs caller
to ensure 'b < bitmap->max_bit', but it's lost in the virBitmapParse() caller,
this will cause crash of libvirtd, with the patch, libvirtd no crash and can
get a expected error "Failed to parse nodeset".

How to reproduce?

# virsh numatune foo --nodeset 1000000000
Actual result:
error: Unable to change numa parameters
error: End of file while reading data: Input/output error
error: One or more references were leaked after disconnect from the hypervisor
error: Failed to reconnect to the hypervisor

GDB backtrace:

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 0x7f80ee533700 (LWP 4156)]
0x00007f80fb1b8906 in virBitmapIsSet (str=<value optimized out>, terminator=0 
'\000', bitmap=0x7f80ee532978, bitmapSize=<value optimized out>)
    at util/virbitmap.c:158
158         return !!(bitmap->map[VIR_BITMAP_UNIT_OFFSET(b)] & 
VIR_BITMAP_BIT(b));
(gdb) bt
#0  0x00007f80fb1b8906 in virBitmapIsSet (str=<value optimized out>, 
terminator=0 '\000', bitmap=0x7f80ee532978, bitmapSize=<value optimized out>)
    at util/virbitmap.c:158
#1  virBitmapParse (str=<value optimized out>, terminator=0 '\000', 
bitmap=0x7f80ee532978, bitmapSize=<value optimized out>) at util/virbitmap.c:351
#2  0x00007f80e5e7ef6b in qemuDomainSetNumaParameters (dom=<value optimized 
out>, params=<value optimized out>, nparams=1, flags=2) at 
qemu/qemu_driver.c:8357
#3  0x00007f80fb2ad7c6 in virDomainSetNumaParameters (domain=0x7f80d4000930, 
params=0x7f80d4000b00, nparams=1, flags=0) at libvirt.c:4163
#4  0x00007f80fbcd17ec in remoteDispatchDomainSetNumaParameters (server=<value 
optimized out>, client=<value optimized out>, msg=<value optimized out>,
    rerr=0x7f80ee532ba0, args=<value optimized out>, ret=<value optimized out>) 
at remote_dispatch.h:7771
#5  remoteDispatchDomainSetNumaParametersHelper (server=<value optimized out>, 
client=<value optimized out>, msg=<value optimized out>, rerr=0x7f80ee532ba0,
    args=<value optimized out>, ret=<value optimized out>) at 
remote_dispatch.h:7741
#6  0x00007f80fb2f6518 in virNetServerProgramDispatchCall (prog=0x7f80fd33a990, 
server=0x7f80fd32f3e0, client=0x7f80fd33fe30, msg=0x7f80fd33e550)
    at rpc/virnetserverprogram.c:435
#7  virNetServerProgramDispatch (prog=0x7f80fd33a990, server=0x7f80fd32f3e0, 
client=0x7f80fd33fe30, msg=0x7f80fd33e550) at rpc/virnetserverprogram.c:305
#8  0x00007f80fb2f9dd6 in virNetServerProcessMsg (srv=<value optimized out>, 
client=0x7f80fd33fe30, prog=<value optimized out>, msg=0x7f80fd33e550)
    at rpc/virnetserver.c:165
#9  0x00007f80fb2fa9f3 in virNetServerHandleJob (jobOpaque=<value optimized 
out>, opaque=<value optimized out>) at rpc/virnetserver.c:186
#10 0x00007f80fb20210e in virThreadPoolWorker (opaque=<value optimized out>) at 
util/virthreadpool.c:144
#11 0x00007f80fb2016f6 in virThreadHelper (data=<value optimized out>) at 
util/virthreadpthread.c:161
#12 0x00007f80f8d857f1 in start_thread (arg=0x7f80ee533700) at 
pthread_create.c:301
#13 0x00007f80f86bb70d in clone () at 
../sysdeps/unix/sysv/linux/x86_64/clone.S:115

RHBZ: https://bugzilla.redhat.com/show_bug.cgi?id=997367

Signed-off-by: Alex Jia <a...@redhat.com>
---
The caller virBitmapGetBit() can make sure 'b < bitmap->max_bit', so don't
need to worry about higher caller for the virBitmapGetBit(), but the
virBitmapParse() is called by many XML parser function, not sure which one
can crash libvirtd with read-only client then probably require a CVE, I haven't
a good way to check them now and only manually check them one by one.

 src/util/virbitmap.c |    3 +++
 1 files changed, 3 insertions(+), 0 deletions(-)

diff --git a/src/util/virbitmap.c b/src/util/virbitmap.c
index 7e1cd02..edbfb30 100644
--- a/src/util/virbitmap.c
+++ b/src/util/virbitmap.c
@@ -337,6 +337,9 @@ virBitmapParse(const char *str,
         if (start < 0)
             goto parse_error;
 
+        if ((*bitmap)->max_bit <= start)
+            goto parse_error;
+
         cur = tmp;
 
         virSkipSpaces(&cur);
-- 
1.7.1

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