* kernel: postnote patch
@ 2020-04-05 4:48 covertusername967
0 siblings, 0 replies; 2+ messages in thread
From: covertusername967 @ 2020-04-05 4:48 UTC (permalink / raw)
To: covertusername976, 9front
Currently, if you do a zero-sized write into the /proc/$pid/note file,
it will post the empty note successfully and cause the process to exit
with no status code. This patch disables zero-sized note strings
altogether.
diff -r f3cc6939a481 sys/src/9/port/proc.c
--- a/sys/src/9/port/proc.c Wed Apr 01 22:57:15 2020 +1030
+++ b/sys/src/9/port/proc.c Sat Apr 04 23:31:39 2020 -0500
@@ -903,6 +903,9 @@
return 0;
}
+ if(strlen(n) == 0)
+ return 0;
+
if(n != nil && flag != NUser && (p->notify == nil || p->notified))
p->nnote = 0;
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: kernel: postnote patch
@ 2020-04-06 14:07 covertusername967
0 siblings, 0 replies; 2+ messages in thread
From: covertusername967 @ 2020-04-06 14:07 UTC (permalink / raw)
To: covertusername967, 9front
Here is a new version of the patch that checks the length of the note
string BEFORE aquiring the p->debug lock if dolock is set (thanks
kvik).
diff -r 8c47f4302b74 sys/src/9/port/proc.c
--- a/sys/src/9/port/proc.c Sun Apr 05 23:26:52 2020 +0930
+++ b/sys/src/9/port/proc.c Mon Apr 06 08:48:52 2020 -0500
@@ -894,6 +894,9 @@
if(p == nil)
return 0;
+ if(strlen(n) == 0)
+ return 0;
+
if(dolock)
qlock(&p->debug);
^ permalink raw reply [flat|nested] 2+ messages in thread
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