Mercurial > vim
changeset 34309:d7cfd8fb1d75 v9.1.0089
patch 9.1.0089: qsort() comparison functions should be transitive
Commit: https://github.com/vim/vim/commit/e06e43766500ecb4cd1031fa16cf9cbebdb222c1
Author: Christian Brabandt <cb@256bit.org>
Date: Fri Feb 9 19:39:14 2024 +0100
patch 9.1.0089: qsort() comparison functions should be transitive
Problem: qsort() comparison functions should be transitive
Solution: Do not subtract values, but rather use explicit comparisons
Improve qsort() comparison functions
There has been a recent report on qsort() causing out-of-bounds read &
write in glibc for non transitive comparison functions
https://www.qualys.com/2024/01/30/qsort.txt
Even so the bug is in glibc's implementation of the qsort() algorithm,
it's bad style to just use substraction for the comparison functions,
which may cause overflow issues and as hinted at in OpenBSD's manual
page for qsort(): "It is almost always an error to use subtraction to
compute the return value of the comparison function."
So check the qsort() comparison functions and change them to be safe.
closes: #13980
Signed-off-by: Christian Brabandt <cb@256bit.org>
| author | Christian Brabandt <cb@256bit.org> |
|---|---|
| date | Fri, 09 Feb 2024 19:45:06 +0100 |
| parents | 781c39b50ce9 |
| children | d6a6049a0965 |
| files | src/ex_cmds.c src/mbyte.c src/profiler.c src/search.c src/spellsuggest.c src/version.c src/window.c |
| diffstat | 7 files changed, 38 insertions(+), 14 deletions(-) [+] |
line wrap: on
line diff
--- a/src/ex_cmds.c +++ b/src/ex_cmds.c @@ -323,7 +323,7 @@ sort_compare(const void *s1, const void if (sort_nr) { if (l1.st_u.num.is_number != l2.st_u.num.is_number) - result = l1.st_u.num.is_number - l2.st_u.num.is_number; + result = l1.st_u.num.is_number > l2.st_u.num.is_number ? 1 : -1; else result = l1.st_u.num.value == l2.st_u.num.value ? 0 : l1.st_u.num.value > l2.st_u.num.value ? 1 : -1;
--- a/src/mbyte.c +++ b/src/mbyte.c @@ -5613,7 +5613,8 @@ tv_nr_compare(const void *a1, const void listitem_T *li1 = *(listitem_T **)a1; listitem_T *li2 = *(listitem_T **)a2; - return li1->li_tv.vval.v_number - li2->li_tv.vval.v_number; + return li1->li_tv.vval.v_number == li2->li_tv.vval.v_number ? 0 : + li1->li_tv.vval.v_number > li2->li_tv.vval.v_number ? 1 : -1; } void
--- a/src/profiler.c +++ b/src/profiler.c @@ -287,11 +287,13 @@ profile_equal(proftime_T *tm1, proftime_ profile_cmp(const proftime_T *tm1, const proftime_T *tm2) { # ifdef MSWIN - return (int)(tm2->QuadPart - tm1->QuadPart); + return tm2->QuadPart == tm1->QuadPart ? 0 : + tm2->QuadPart > tm1->QuadPart ? 1 : -1; # else if (tm1->tv_sec == tm2->tv_sec) - return tm2->tv_fsec - tm1->tv_fsec; - return tm2->tv_sec - tm1->tv_sec; + return tm2->tv_fsec == tm1->tv_fsec ? 0 : + tm2->tv_fsec > tm1->tv_fsec ? 1 : -1; + return tm2->tv_sec > tm1->tv_sec ? 1 : -1; # endif }
--- a/src/search.c +++ b/src/search.c @@ -4908,7 +4908,10 @@ fuzzy_match_str_compare(const void *s1, int idx1 = ((fuzmatch_str_T *)s1)->idx; int idx2 = ((fuzmatch_str_T *)s2)->idx; - return v1 == v2 ? (idx1 - idx2) : v1 > v2 ? -1 : 1; + if (v1 == v2) + return idx1 == idx2 ? 0 : idx1 > idx2 ? 1 : -1; + else + return v1 > v2 ? -1 : 1; } /* @@ -4936,9 +4939,14 @@ fuzzy_match_func_compare(const void *s1, char_u *str1 = ((fuzmatch_str_T *)s1)->str; char_u *str2 = ((fuzmatch_str_T *)s2)->str; - if (*str1 != '<' && *str2 == '<') return -1; - if (*str1 == '<' && *str2 != '<') return 1; - return v1 == v2 ? (idx1 - idx2) : v1 > v2 ? -1 : 1; + if (*str1 != '<' && *str2 == '<') + return -1; + if (*str1 == '<' && *str2 != '<') + return 1; + if (v1 == v2) + return idx1 == idx2 ? 0 : idx1 > idx2 ? 1 : -1; + else + return v1 > v2 ? -1 : 1; } /*
--- a/src/spellsuggest.c +++ b/src/spellsuggest.c @@ -3763,11 +3763,16 @@ sug_compare(const void *s1, const void * { suggest_T *p1 = (suggest_T *)s1; suggest_T *p2 = (suggest_T *)s2; - int n = p1->st_score - p2->st_score; + int n; + + n = p1->st_score == p2->st_score ? 0 : + p1->st_score > p2->st_score ? 1 : -1; if (n == 0) { - n = p1->st_altscore - p2->st_altscore; + n = p1->st_altscore == p2->st_altscore ? 0 : + p1->st_altscore > p2->st_altscore ? 1 : -1; + if (n == 0) n = STRICMP(p1->st_word, p2->st_word); }
--- a/src/version.c +++ b/src/version.c @@ -705,6 +705,8 @@ static char *(features[]) = static int included_patches[] = { /* Add new patch number below this line */ /**/ + 89, +/**/ 88, /**/ 87,
--- a/src/window.c +++ b/src/window.c @@ -7753,9 +7753,15 @@ frame_check_width(frame_T *topfrp, int w * Simple int comparison function for use with qsort() */ static int -int_cmp(const void *a, const void *b) -{ - return *(const int *)a - *(const int *)b; +int_cmp(const void *pa, const void *pb) +{ + const int a = *(const int *)pa; + const int b = *(const int *)pb; + if (a > b) + return 1; + if (a < b) + return -1; + return 0; } /*