From 08a5dab181fa4c28b7636c35021308e1e12e7b59 Mon Sep 17 00:00:00 2001
From: Denys Vlasenko <vda.linux@googlemail.com>
Date: Mon, 17 Nov 2014 20:27:18 +0100
Subject: ash: fix handling of negative start value in ${v:start:len}
function old new delta
subevalvar 1140 1168 +28
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
---
shell/ash.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
(limited to 'shell')
diff --git a/shell/ash.c b/shell/ash.c
index 705fe9fa4..90fb00fbd 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -6411,7 +6411,15 @@ subevalvar(char *p, char *varname, int strloc, int subtype,
len = number(loc);
}
}
- if (pos >= orig_len) {
+ if (pos < 0) {
+ /* ${VAR:$((-n)):l} starts n chars from the end */
+ pos = orig_len + pos;
+ }
+ if ((unsigned)pos >= orig_len) {
+ /* apart from obvious ${VAR:999999:l},
+ * covers ${VAR:$((-9999999)):l} - result is ""
+ * (bash-compat)
+ */
pos = 0;
len = 0;
}
--
cgit v1.2.3-55-g6feb
From 8a475def9e3e21f780ebcf07dd607b26ceb00ea8 Mon Sep 17 00:00:00 2001
From: Denys Vlasenko <vda.linux@googlemail.com>
Date: Tue, 18 Nov 2014 14:32:58 +0100
Subject: ash,hush: do not segfault on $((2**63 / -1))
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
---
shell/math.c | 27 +++++++++++++++++++++++----
1 file changed, 23 insertions(+), 4 deletions(-)
(limited to 'shell')
diff --git a/shell/math.c b/shell/math.c
index 3da151137..e7565ebf2 100644
--- a/shell/math.c
+++ b/shell/math.c
@@ -415,10 +415,29 @@ arith_apply(arith_state_t *math_state, operator op, var_or_num_t *numstack, var_
}
else if (right_side_val == 0)
return "divide by zero";
- else if (op == TOK_DIV || op == TOK_DIV_ASSIGN)
- rez /= right_side_val;
- else if (op == TOK_REM || op == TOK_REM_ASSIGN)
- rez %= right_side_val;
+ else if (op == TOK_DIV || op == TOK_DIV_ASSIGN
+ || op == TOK_REM || op == TOK_REM_ASSIGN) {
+ /*
+ * bash 4.2.45 x86 64bit: SEGV on 'echo $((2**63 / -1))'
+ *
+ * MAX_NEGATIVE_INT / -1 = MAX_POSITIVE_INT+1
+ * and thus is not representable.
+ * Some CPUs segfault trying such op.
+ * Others overfolw MAX_POSITIVE_INT+1 to
+ * MAX_NEGATIVE_INT (0x7fff+1 = 0x8000).
+ * Make sure to at least not SEGV here:
+ */
+ if (right_side_val == -1
+ && rez << 1 == 0 /* MAX_NEGATIVE_INT or 0 */
+ ) {
+ right_side_val = 1;
+ }
+ if (op == TOK_DIV || op == TOK_DIV_ASSIGN)
+ rez /= right_side_val;
+ else {
+ rez %= right_side_val;
+ }
+ }
}
if (is_assign_op(op)) {
--
cgit v1.2.3-55-g6feb
From f5add44981b43490376ea0dfed1420dba09a3a75 Mon Sep 17 00:00:00 2001
From: Denys Vlasenko <vda.linux@googlemail.com>
Date: Thu, 20 Nov 2014 01:43:30 +0100
Subject: typo fix in comment
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
---
shell/math.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
(limited to 'shell')
diff --git a/shell/math.c b/shell/math.c
index e7565ebf2..006221b6a 100644
--- a/shell/math.c
+++ b/shell/math.c
@@ -423,7 +423,7 @@ arith_apply(arith_state_t *math_state, operator op, var_or_num_t *numstack, var_
* MAX_NEGATIVE_INT / -1 = MAX_POSITIVE_INT+1
* and thus is not representable.
* Some CPUs segfault trying such op.
- * Others overfolw MAX_POSITIVE_INT+1 to
+ * Others overflow MAX_POSITIVE_INT+1 to
* MAX_NEGATIVE_INT (0x7fff+1 = 0x8000).
* Make sure to at least not SEGV here:
*/
--
cgit v1.2.3-55-g6feb