From 45dd87aac05ddf8bbfb110fde85ef875f3adfb65 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Fri, 21 Feb 2020 16:30:44 +0100 Subject: [PATCH] ash: expand: Ensure result is escaped in cvtnum Upstream commit: Date: Fri, 1 Jun 2018 18:25:29 +0800 expand: Ensure result is escaped in cvtnum The minus sign generated from arithmetic expansion is currently unquoted which causes anomalies when the result is used in where the quoting matters. This patch fixes it by explicitly calling memtodest on the result in cvtnum. Signed-off-by: Herbert Xu Signed-off-by: Denys Vlasenko --- shell/ash.c | 49 +++++++++---------- .../ash_test/ash-quoting/negative_arith.right | 2 + .../ash_test/ash-quoting/negative_arith.tests | 8 +++ .../hush-quoting/negative_arith.right | 2 + .../hush-quoting/negative_arith.tests | 8 +++ 5 files changed, 44 insertions(+), 25 deletions(-) create mode 100644 shell/ash_test/ash-quoting/negative_arith.right create mode 100755 shell/ash_test/ash-quoting/negative_arith.tests create mode 100644 shell/hush_test/hush-quoting/negative_arith.right create mode 100755 shell/hush_test/hush-quoting/negative_arith.tests diff --git a/shell/ash.c b/shell/ash.c index 8d1822847..005d87ecf 100644 --- a/shell/ash.c +++ b/shell/ash.c @@ -6070,26 +6070,6 @@ static struct ifsregion *ifslastp; /* holds expanded arg list */ static struct arglist exparg; -/* - * Our own itoa(). - * cvtnum() is used even if math support is off (to prepare $? values and such). - */ -static int -cvtnum(arith_t num) -{ - int len; - - /* 32-bit and wider ints require buffer size of bytes*3 (or less) */ - len = sizeof(arith_t) * 3; - /* If narrower: worst case, 1-byte ints: need 5 bytes: "-127" */ - if (sizeof(arith_t) < 4) len += 2; - - expdest = makestrspace(len, expdest); - len = fmtstr(expdest, len, ARITH_FMT, num); - STADJUST(len, expdest); - return len; -} - /* * Break the argument string into pieces based upon IFS and add the * strings to the argument list. The regions of the string to be @@ -6347,16 +6327,18 @@ preglob(const char *pattern, int flag) /* * Put a string on the stack. */ -static void +static size_t memtodest(const char *p, size_t len, int flags) { int syntax = flags & EXP_QUOTED ? DQSYNTAX : BASESYNTAX; char *q; + char *s; if (!len) - return; + return 0; q = makestrspace(len * 2, expdest); + s = q; do { unsigned char c = *p++; @@ -6375,6 +6357,7 @@ memtodest(const char *p, size_t len, int flags) } while (--len); expdest = q; + return q - s; } static size_t @@ -6385,6 +6368,22 @@ strtodest(const char *p, int flags) return len; } +/* + * Our own itoa(). + * cvtnum() is used even if math support is off (to prepare $? values and such). + */ +static int +cvtnum(arith_t num, int flags) +{ + /* 32-bit and wider ints require buffer size of bytes*3 (or less) */ + /* If narrower: worst case, 1-byte ints: need 5 bytes: "-127" */ + int len = (sizeof(arith_t) >= 4) ? sizeof(arith_t) * 3 : sizeof(arith_t) * 3 + 2; + char buf[len]; + + len = fmtstr(buf, len, ARITH_FMT, num); + return memtodest(buf, len, flags); +} + /* * Record the fact that we have to scan this region of the * string for IFS characters. @@ -6683,7 +6682,7 @@ expari(int flag) if (flag & QUOTES_ESC) rmescapes(p + 1, 0, NULL); - len = cvtnum(ash_arith(p + 1)); + len = cvtnum(ash_arith(p + 1), flag); if (!(flag & EXP_QUOTED)) recordregion(begoff, begoff + len, 0); @@ -7328,7 +7327,7 @@ varvalue(char *name, int varflags, int flags, int quoted) if (num == 0) return -1; numvar: - len = cvtnum(num); + len = cvtnum(num, flags); goto check_1char_name; case '-': expdest = makestrspace(NOPTS, expdest); @@ -7494,7 +7493,7 @@ evalvar(char *p, int flag) varunset(p, var, 0, 0); if (subtype == VSLENGTH) { - cvtnum(varlen > 0 ? varlen : 0); + cvtnum(varlen > 0 ? varlen : 0, flag); goto record; } diff --git a/shell/ash_test/ash-quoting/negative_arith.right b/shell/ash_test/ash-quoting/negative_arith.right new file mode 100644 index 000000000..e7e51eee7 --- /dev/null +++ b/shell/ash_test/ash-quoting/negative_arith.right @@ -0,0 +1,2 @@ +tempfile0.tmp tempfile9.tmp +tempfile0.tmp tempfile1.tmp tempfile9.tmp diff --git a/shell/ash_test/ash-quoting/negative_arith.tests b/shell/ash_test/ash-quoting/negative_arith.tests new file mode 100755 index 000000000..8e47ca111 --- /dev/null +++ b/shell/ash_test/ash-quoting/negative_arith.tests @@ -0,0 +1,8 @@ +>tempfile0.tmp +>tempfile1.tmp +>tempfile9.tmp +# The [...] is interpreted as: "any of the chars 0, -, and 9" +echo tempfile[0"$((-9))"].tmp +# The [...] is [0-9], interpreted as: "any digit" +echo tempfile[0$((-9))].tmp +rm tempfile?.tmp diff --git a/shell/hush_test/hush-quoting/negative_arith.right b/shell/hush_test/hush-quoting/negative_arith.right new file mode 100644 index 000000000..e7e51eee7 --- /dev/null +++ b/shell/hush_test/hush-quoting/negative_arith.right @@ -0,0 +1,2 @@ +tempfile0.tmp tempfile9.tmp +tempfile0.tmp tempfile1.tmp tempfile9.tmp diff --git a/shell/hush_test/hush-quoting/negative_arith.tests b/shell/hush_test/hush-quoting/negative_arith.tests new file mode 100755 index 000000000..8e47ca111 --- /dev/null +++ b/shell/hush_test/hush-quoting/negative_arith.tests @@ -0,0 +1,8 @@ +>tempfile0.tmp +>tempfile1.tmp +>tempfile9.tmp +# The [...] is interpreted as: "any of the chars 0, -, and 9" +echo tempfile[0"$((-9))"].tmp +# The [...] is [0-9], interpreted as: "any digit" +echo tempfile[0$((-9))].tmp +rm tempfile?.tmp