diff options
| author | cinap_lenrek <cinap_lenrek@felloff.net> | 2013-12-29 06:11:18 +0100 |
|---|---|---|
| committer | cinap_lenrek <cinap_lenrek@felloff.net> | 2013-12-29 06:11:18 +0100 |
| commit | afc2d547e18381ce2dd0f69f0e88860d49b7e54f (patch) | |
| tree | b39279a3e41a12701297a1b7f57561b10155bf96 | |
| parent | 8cef1794d6a092e72482bcb4927fced3b7b75d2a (diff) | |
kernel: make sure user text, data and bss wont overlap the stack segment in sysexec()
| -rw-r--r-- | sys/src/9/port/sysproc.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/sys/src/9/port/sysproc.c b/sys/src/9/port/sysproc.c index fbad6942f..ab37bb68c 100644 --- a/sys/src/9/port/sysproc.c +++ b/sys/src/9/port/sysproc.c @@ -283,7 +283,7 @@ sysexec(ulong *arg) text = l2be(exec.text); entry = l2be(exec.entry); if(n==sizeof(Exec) && (magic == AOUT_MAGIC)){ - if(text >= USTKTOP-UTZERO + if(text >= (USTKTOP-USTKSIZE)-(UTZERO+sizeof(Exec)) || entry < UTZERO+sizeof(Exec) || entry >= UTZERO+sizeof(Exec)+text) error(Ebadexec); @@ -322,7 +322,7 @@ sysexec(ulong *arg) d = (t + data + (BY2PG-1)) & ~(BY2PG-1); bssend = t + data + bss; b = (bssend + (BY2PG-1)) & ~(BY2PG-1); - if(t >= KZERO || d >= KZERO || b >= KZERO) + if(t >= (USTKTOP-USTKSIZE) || d >= (USTKTOP-USTKSIZE) || b >= (USTKTOP-USTKSIZE)) error(Ebadexec); /* |