xfnw/plan9fox
1
0
Fork 0
Code Issues Pull requests Projects Releases Wiki Activity

kernel: make sure fd is in range in fdclose()

Browse source 
as the Fgrp can be shared with other processes, we have to
recheck the fd index after locking the Fgrp in fdclose()
to make sure not to read beyond the bounds of the fd array.
This commit is contained in:
cinap_lenrek 2015-07-23 22:56:49 +02:00
parent 323184d775
commit 497daed116
1 changed files with 1 additions and 1 deletions
Download patch file Download diff file Expand all files Collapse all files

2
sys/src/9/port/sysfile.c
View file

@ -294,7 +294,7 @@ fdclose(int fd, int flag)
Fgrp *f = up->fgrp;
lock(f);
c = f->fd[fd];
c = fd <= f->maxfd ? f->fd[fd] : nil;
if(c == nil || (flag != 0 && (c->flag&flag) == 0)){
unlock(f);
return;