154 lines
5.5 KiB
Diff
154 lines
5.5 KiB
Diff
From 4604df9ada906e0a6537157a63b6ce7c0509f34d Mon Sep 17 00:00:00 2001
|
|
From: Martijn Dekker <martijn@inlv.org>
|
|
Date: Thu, 28 Jan 2021 06:08:38 +0000
|
|
Subject: [PATCH] Stack robustness fixes from OpenSUSE
|
|
|
|
Three OpenSUSE patches from:
|
|
https://build.opensuse.org/package/show/shells/ksh
|
|
|
|
As usual, the relevant bug is not currently public:
|
|
https://bugzilla.opensuse.org/show_bug.cgi?id=844071
|
|
|
|
src/cmd/ksh93/sh/xec.c: sh_debug()/sh_exec():
|
|
- Fix stk restoration. [bnc#844071]
|
|
|
|
src/lib/libast/misc/stk.c:
|
|
- Fix stk aliasing code. [bnc#844071]
|
|
(ksh93-stkalias.dif)
|
|
- Make a unknown location fatal in stkset() so that we get a core
|
|
dump right away instead of later in an unrelated part of code.
|
|
(ksh93-stkset-abort.dif)
|
|
|
|
src/lib/libast/man/stk.3,
|
|
src/lib/libast/man/stak.3:
|
|
- Update manual with new stkset() behaviour. (93u+m addition)
|
|
(Note that stak is implemented as macros that translate to stk)
|
|
---
|
|
src/cmd/ksh93/sh/xec.c | 6 +++---
|
|
src/lib/libast/man/stak.3 | 5 +++--
|
|
src/lib/libast/man/stk.3 | 5 +++--
|
|
src/lib/libast/misc/stk.c | 16 ++++++++++------
|
|
4 files changed, 19 insertions(+), 13 deletions(-)
|
|
|
|
diff --git a/src/cmd/ksh93/sh/xec.c b/src/cmd/ksh93/sh/xec.c
|
|
index 23526098ec20..ca3876394d63 100644
|
|
--- a/src/cmd/ksh93/sh/xec.c
|
|
+++ b/src/cmd/ksh93/sh/xec.c
|
|
@@ -646,8 +646,8 @@ int sh_debug(Shell_t *shp, const char *trap, const char *name, const char *subsc
|
|
Stk_t *stkp=shp->stk;
|
|
struct sh_scoped savst;
|
|
Namval_t *np = SH_COMMANDNOD;
|
|
- char *sav = stkptr(stkp,0);
|
|
int n=4, offset=stktell(stkp);
|
|
+ char *sav = stkfreeze(stkp,0);
|
|
const char *cp = "+=( ";
|
|
Sfio_t *iop = stkstd;
|
|
short level;
|
|
@@ -702,7 +702,7 @@ int sh_debug(Shell_t *shp, const char *trap, const char *name, const char *subsc
|
|
nv_putval(SH_FUNNAMENOD,shp->st.funname,NV_NOFREE);
|
|
shp->st = savst;
|
|
if(sav != stkptr(stkp,0))
|
|
- stkset(stkp,sav,0);
|
|
+ stkset(stkp,sav,offset);
|
|
else
|
|
stkseek(stkp,offset);
|
|
return(n);
|
|
@@ -962,7 +962,7 @@ int sh_exec(register const Shnode_t *t, int flags)
|
|
int ntflag = 0;
|
|
#endif
|
|
int topfd = shp->topfd;
|
|
- char *sav=stkptr(stkp,0);
|
|
+ char *sav=stkfreeze(stkp,0);
|
|
char *cp=0, **com=0, *comn;
|
|
int argn;
|
|
int skipexitset = 0;
|
|
diff --git a/src/lib/libast/man/stak.3 b/src/lib/libast/man/stak.3
|
|
index 5feac69..89e0f54 100644
|
|
--- a/src/lib/libast/man/stak.3
|
|
+++ b/src/lib/libast/man/stak.3
|
|
@@ -109,8 +109,9 @@ the given \fIaddress\fP, and sets the current object to the given
|
|
\fIaddress\fP.
|
|
The top of the current object is set to \fIoffset\fP bytes from
|
|
current object.
|
|
-If \fIaddress\fP is not the address of an object on the
|
|
-stack the result is undefined.
|
|
+If \fIaddress\fP is null, the stack is reset to the beginning.
|
|
+If it is non-null, but is not the address of an object on the
|
|
+stack, the program aborts and dumps core.
|
|
.PP
|
|
The remaining functions are used to build the current object incrementally.
|
|
An object that is built incrementally on the stack will
|
|
diff --git a/src/lib/libast/man/stk.3 b/src/lib/libast/man/stk.3
|
|
index 20dfdbefa44c..dd5705cf1188 100644
|
|
--- a/src/lib/libast/man/stk.3
|
|
+++ b/src/lib/libast/man/stk.3
|
|
@@ -110,8 +110,9 @@ the given \fIaddress\fP, and sets the current object to the given
|
|
\fIaddress\fP.
|
|
The top of the current object is set to \fIoffset\fP bytes from
|
|
current object.
|
|
-If \fIaddress\fP is not the address of an object on the
|
|
-stack the result is undefined.
|
|
+If \fIaddress\fP is null, the stack is reset to the beginning.
|
|
+If it is non-null, but is not the address of an object on the
|
|
+stack, the program aborts and dumps core.
|
|
.PP
|
|
The \f5sfio\fP(3) output functions can be used to build
|
|
current object incrementally.
|
|
diff --git a/src/lib/libast/misc/stk.c b/src/lib/libast/misc/stk.c
|
|
index 31cd0911dd29..f147ae4fec8c 100644
|
|
--- a/src/lib/libast/misc/stk.c
|
|
+++ b/src/lib/libast/misc/stk.c
|
|
@@ -331,9 +331,9 @@ int stkon(register Sfio_t * stream, register char* loc)
|
|
}
|
|
/*
|
|
* reset the bottom of the current stack back to <loc>
|
|
- * if <loc> is not in this stack, then the stack is reset to the beginning
|
|
+ * if <loc> is null, then the stack is reset to the beginning
|
|
+ * if <loc> is not in this stack, the program dumps core
|
|
* otherwise, the top of the stack is set to stkbot+<offset>
|
|
- *
|
|
*/
|
|
char *stkset(register Sfio_t * stream, register char* loc, size_t offset)
|
|
{
|
|
@@ -377,6 +377,9 @@ char *stkset(register Sfio_t * stream, register char* loc, size_t offset)
|
|
break;
|
|
frames++;
|
|
}
|
|
+ /* not found: produce a useful stack trace now instead of a useless one later */
|
|
+ if(loc)
|
|
+ abort();
|
|
/* set stack back to the beginning */
|
|
cp = (char*)(fp+1);
|
|
if(frames)
|
|
@@ -503,7 +506,7 @@ static char *stkgrow(register Sfio_t *stream, size_t size)
|
|
register char *cp, *dp=0;
|
|
register size_t m = stktell(stream);
|
|
size_t endoff;
|
|
- char *end=0;
|
|
+ char *end=0, *oldbase=0;
|
|
int nn=0,add=1;
|
|
n += (m + sizeof(struct frame)+1);
|
|
if(sp->stkflags&STK_SMALL)
|
|
@@ -519,6 +522,7 @@ static char *stkgrow(register Sfio_t *stream, size_t size)
|
|
dp=sp->stkbase;
|
|
sp->stkbase = ((struct frame*)dp)->prev;
|
|
end = fp->end;
|
|
+ oldbase = dp;
|
|
}
|
|
endoff = end - dp;
|
|
cp = newof(dp, char, n, nn*sizeof(char*));
|
|
@@ -545,10 +549,10 @@ static char *stkgrow(register Sfio_t *stream, size_t size)
|
|
if(fp->nalias=nn)
|
|
{
|
|
fp->aliases = (char**)fp->end;
|
|
- if(end && nn>1)
|
|
- memmove(fp->aliases,end,(nn-1)*sizeof(char*));
|
|
+ if(end && nn>add)
|
|
+ memmove(fp->aliases,end,(nn-add)*sizeof(char*));
|
|
if(add)
|
|
- fp->aliases[nn-1] = dp + roundof(sizeof(struct frame),STK_ALIGN);
|
|
+ fp->aliases[nn-1] = oldbase + roundof(sizeof(struct frame),STK_ALIGN);
|
|
}
|
|
if(m && !dp)
|
|
{
|