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gitstergitster
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Merge branch 'ps/attr-limits' into maint-2.30
2 parents 3305300 + 3c50032 commit 6662a83

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3 files changed

+132
-36
lines changed

3 files changed

+132
-36
lines changed

‎attr.c

Lines changed: 61 additions & 36 deletions
Original file line numberDiff line numberDiff line change
@@ -28,7 +28,7 @@ static const char git_attr__unknown[] = "(builtin)unknown";
2828
#endif
2929

3030
struct git_attr {
31-
int attr_nr; /* unique attribute number */
31+
unsigned int attr_nr; /* unique attribute number */
3232
char name[FLEX_ARRAY]; /* attribute name */
3333
};
3434

@@ -210,7 +210,7 @@ static void report_invalid_attr(const char *name, size_t len,
210210
* dictionary. If no entry is found, create a new attribute and store it in
211211
* the dictionary.
212212
*/
213-
static const struct git_attr *git_attr_internal(const char *name, int namelen)
213+
static const struct git_attr *git_attr_internal(const char *name, size_t namelen)
214214
{
215215
struct git_attr *a;
216216

@@ -226,8 +226,8 @@ static const struct git_attr *git_attr_internal(const char *name, int namelen)
226226
a->attr_nr = hashmap_get_size(&g_attr_hashmap.map);
227227

228228
attr_hashmap_add(&g_attr_hashmap, a->name, namelen, a);
229-
assert(a->attr_nr ==
230-
(hashmap_get_size(&g_attr_hashmap.map) - 1));
229+
if (a->attr_nr != hashmap_get_size(&g_attr_hashmap.map) - 1)
230+
die(_("unable to add additional attribute"));
231231
}
232232

233233
hashmap_unlock(&g_attr_hashmap);
@@ -272,7 +272,7 @@ struct match_attr {
272272
const struct git_attr *attr;
273273
} u;
274274
char is_macro;
275-
unsigned num_attr;
275+
size_t num_attr;
276276
struct attr_state state[FLEX_ARRAY];
277277
};
278278

@@ -289,7 +289,7 @@ static const char *parse_attr(const char *src, int lineno, const char *cp,
289289
struct attr_state *e)
290290
{
291291
const char *ep, *equals;
292-
int len;
292+
size_t len;
293293

294294
ep = cp + strcspn(cp, blank);
295295
equals = strchr(cp, '=');
@@ -333,8 +333,7 @@ static const char *parse_attr(const char *src, int lineno, const char *cp,
333333
static struct match_attr *parse_attr_line(const char *line, const char *src,
334334
int lineno, int macro_ok)
335335
{
336-
int namelen;
337-
int num_attr, i;
336+
size_t namelen, num_attr, i;
338337
const char *cp, *name, *states;
339338
struct match_attr *res = NULL;
340339
int is_macro;
@@ -345,6 +344,11 @@ static struct match_attr *parse_attr_line(const char *line, const char *src,
345344
return NULL;
346345
name = cp;
347346

347+
if (strlen(line) >= ATTR_MAX_LINE_LENGTH) {
348+
warning(_("ignoring overly long attributes line %d"), lineno);
349+
return NULL;
350+
}
351+
348352
if (*cp == '"' && !unquote_c_style(&pattern, name, &states)) {
349353
name = pattern.buf;
350354
namelen = pattern.len;
@@ -381,10 +385,9 @@ static struct match_attr *parse_attr_line(const char *line, const char *src,
381385
goto fail_return;
382386
}
383387

384-
res = xcalloc(1,
385-
sizeof(*res) +
386-
sizeof(struct attr_state) * num_attr +
387-
(is_macro ? 0 : namelen + 1));
388+
res = xcalloc(1, st_add3(sizeof(*res),
389+
st_mult(sizeof(struct attr_state), num_attr),
390+
is_macro ? 0 : namelen + 1));
388391
if (is_macro) {
389392
res->u.attr = git_attr_internal(name, namelen);
390393
} else {
@@ -447,11 +450,12 @@ struct attr_stack {
447450

448451
static void attr_stack_free(struct attr_stack *e)
449452
{
450-
int i;
453+
unsigned i;
451454
free(e->origin);
452455
for (i = 0; i < e->num_matches; i++) {
453456
struct match_attr *a = e->attrs[i];
454-
int j;
457+
size_t j;
458+
455459
for (j = 0; j < a->num_attr; j++) {
456460
const char *setto = a->state[j].setto;
457461
if (setto == ATTR__TRUE ||
@@ -660,8 +664,8 @@ static void handle_attr_line(struct attr_stack *res,
660664
a = parse_attr_line(line, src, lineno, macro_ok);
661665
if (!a)
662666
return;
663-
ALLOC_GROW(res->attrs, res->num_matches + 1, res->alloc);
664-
res->attrs[res->num_matches++] = a;
667+
ALLOC_GROW_BY(res->attrs, res->num_matches, 1, res->alloc);
668+
res->attrs[res->num_matches - 1] = a;
665669
}
666670

667671
static struct attr_stack *read_attr_from_array(const char **list)
@@ -700,21 +704,37 @@ void git_attr_set_direction(enum git_attr_direction new_direction)
700704

701705
static struct attr_stack *read_attr_from_file(const char *path, int macro_ok)
702706
{
707+
struct strbuf buf = STRBUF_INIT;
703708
FILE *fp = fopen_or_warn(path, "r");
704709
struct attr_stack *res;
705-
char buf[2048];
706710
int lineno = 0;
711+
int fd;
712+
struct stat st;
707713

708714
if (!fp)
709715
return NULL;
710-
res = xcalloc(1, sizeof(*res));
711-
while (fgets(buf, sizeof(buf), fp)) {
712-
char *bufp = buf;
713-
if (!lineno)
714-
skip_utf8_bom(&bufp, strlen(bufp));
715-
handle_attr_line(res, bufp, path, ++lineno, macro_ok);
716+
717+
fd = fileno(fp);
718+
if (fstat(fd, &st)) {
719+
warning_errno(_("cannot fstat gitattributes file '%s'"), path);
720+
fclose(fp);
721+
return NULL;
716722
}
723+
if (st.st_size >= ATTR_MAX_FILE_SIZE) {
724+
warning(_("ignoring overly large gitattributes file '%s'"), path);
725+
fclose(fp);
726+
return NULL;
727+
}
728+
729+
CALLOC_ARRAY(res, 1);
730+
while (strbuf_getline(&buf, fp) != EOF) {
731+
if (!lineno && starts_with(buf.buf, utf8_bom))
732+
strbuf_remove(&buf, 0, strlen(utf8_bom));
733+
handle_attr_line(res, buf.buf, path, ++lineno, macro_ok);
734+
}
735+
717736
fclose(fp);
737+
strbuf_release(&buf);
718738
return res;
719739
}
720740

@@ -725,13 +745,18 @@ static struct attr_stack *read_attr_from_index(const struct index_state *istate,
725745
struct attr_stack *res;
726746
char *buf, *sp;
727747
int lineno = 0;
748+
size_t size;
728749

729750
if (!istate)
730751
return NULL;
731752

732-
buf = read_blob_data_from_index(istate, path, NULL);
753+
buf = read_blob_data_from_index(istate, path, &size);
733754
if (!buf)
734755
return NULL;
756+
if (size >= ATTR_MAX_FILE_SIZE) {
757+
warning(_("ignoring overly large gitattributes blob '%s'"), path);
758+
return NULL;
759+
}
735760

736761
res = xcalloc(1, sizeof(*res));
737762
for (sp = buf; *sp; ) {
@@ -1001,12 +1026,12 @@ static int macroexpand_one(struct all_attrs_item *all_attrs, int nr, int rem);
10011026
static int fill_one(const char *what, struct all_attrs_item *all_attrs,
10021027
const struct match_attr *a, int rem)
10031028
{
1004-
int i;
1029+
size_t i;
10051030

1006-
for (i = a->num_attr - 1; rem > 0 && i >= 0; i--) {
1007-
const struct git_attr *attr = a->state[i].attr;
1031+
for (i = a->num_attr; rem > 0 && i > 0; i--) {
1032+
const struct git_attr *attr = a->state[i - 1].attr;
10081033
const char **n = &(all_attrs[attr->attr_nr].value);
1009-
const char *v = a->state[i].setto;
1034+
const char *v = a->state[i - 1].setto;
10101035

10111036
if (*n == ATTR__UNKNOWN) {
10121037
debug_set(what,
@@ -1025,11 +1050,11 @@ static int fill(const char *path, int pathlen, int basename_offset,
10251050
struct all_attrs_item *all_attrs, int rem)
10261051
{
10271052
for (; rem > 0 && stack; stack = stack->prev) {
1028-
int i;
1053+
unsigned i;
10291054
const char *base = stack->origin ? stack->origin : "";
10301055

1031-
for (i = stack->num_matches - 1; 0 < rem && 0 <= i; i--) {
1032-
const struct match_attr *a = stack->attrs[i];
1056+
for (i = stack->num_matches; 0 < rem && 0 < i; i--) {
1057+
const struct match_attr *a = stack->attrs[i - 1];
10331058
if (a->is_macro)
10341059
continue;
10351060
if (path_matches(path, pathlen, basename_offset,
@@ -1060,11 +1085,11 @@ static void determine_macros(struct all_attrs_item *all_attrs,
10601085
const struct attr_stack *stack)
10611086
{
10621087
for (; stack; stack = stack->prev) {
1063-
int i;
1064-
for (i = stack->num_matches - 1; i >= 0; i--) {
1065-
const struct match_attr *ma = stack->attrs[i];
1088+
unsigned i;
1089+
for (i = stack->num_matches; i > 0; i--) {
1090+
const struct match_attr *ma = stack->attrs[i - 1];
10661091
if (ma->is_macro) {
1067-
int n = ma->u.attr->attr_nr;
1092+
unsigned int n = ma->u.attr->attr_nr;
10681093
if (!all_attrs[n].macro) {
10691094
all_attrs[n].macro = ma;
10701095
}
@@ -1116,7 +1141,7 @@ void git_check_attr(const struct index_state *istate,
11161141
collect_some_attrs(istate, path, check);
11171142

11181143
for (i = 0; i < check->nr; i++) {
1119-
size_t n = check->items[i].attr->attr_nr;
1144+
unsigned int n = check->items[i].attr->attr_nr;
11201145
const char *value = check->all_attrs[n].value;
11211146
if (value == ATTR__UNKNOWN)
11221147
value = ATTR__UNSET;

‎attr.h

Lines changed: 12 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -107,6 +107,18 @@
107107
* - Free the `attr_check` struct by calling `attr_check_free()`.
108108
*/
109109

110+
/**
111+
* The maximum line length for a gitattributes file. If the line exceeds this
112+
* length we will ignore it.
113+
*/
114+
#define ATTR_MAX_LINE_LENGTH 2048
115+
116+
/**
117+
* The maximum size of the giattributes file. If the file exceeds this size we
118+
* will ignore it.
119+
*/
120+
#define ATTR_MAX_FILE_SIZE (100 * 1024 * 1024)
121+
110122
struct index_state;
111123

112124
/**

‎t/t0003-attributes.sh

Lines changed: 59 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -339,4 +339,63 @@ test_expect_success 'query binary macro directly' '
339339
test_cmp expect actual
340340
'
341341

342+
test_expect_success 'large attributes line ignored in tree' '
343+
test_when_finished "rm .gitattributes" &&
344+
printf "path %02043d" 1 >.gitattributes &&
345+
git check-attr --all path >actual 2>err &&
346+
echo "warning: ignoring overly long attributes line 1" >expect &&
347+
test_cmp expect err &&
348+
test_must_be_empty actual
349+
'
350+
351+
test_expect_success 'large attributes line ignores trailing content in tree' '
352+
test_when_finished "rm .gitattributes" &&
353+
# older versions of Git broke lines at 2048 bytes; the 2045 bytes
354+
# of 0-padding here is accounting for the three bytes of "a 1", which
355+
# would knock "trailing" to the "next" line, where it would be
356+
# erroneously parsed.
357+
printf "a %02045dtrailing attribute\n" 1 >.gitattributes &&
358+
git check-attr --all trailing >actual 2>err &&
359+
echo "warning: ignoring overly long attributes line 1" >expect &&
360+
test_cmp expect err &&
361+
test_must_be_empty actual
362+
'
363+
364+
test_expect_success EXPENSIVE 'large attributes file ignored in tree' '
365+
test_when_finished "rm .gitattributes" &&
366+
dd if=/dev/zero of=.gitattributes bs=101M count=1 2>/dev/null &&
367+
git check-attr --all path >/dev/null 2>err &&
368+
echo "warning: ignoring overly large gitattributes file ${SQ}.gitattributes${SQ}" >expect &&
369+
test_cmp expect err
370+
'
371+
372+
test_expect_success 'large attributes line ignored in index' '
373+
test_when_finished "git update-index --remove .gitattributes" &&
374+
blob=$(printf "path %02043d" 1 | git hash-object -w --stdin) &&
375+
git update-index --add --cacheinfo 100644,$blob,.gitattributes &&
376+
git check-attr --cached --all path >actual 2>err &&
377+
echo "warning: ignoring overly long attributes line 1" >expect &&
378+
test_cmp expect err &&
379+
test_must_be_empty actual
380+
'
381+
382+
test_expect_success 'large attributes line ignores trailing content in index' '
383+
test_when_finished "git update-index --remove .gitattributes" &&
384+
blob=$(printf "a %02045dtrailing attribute\n" 1 | git hash-object -w --stdin) &&
385+
git update-index --add --cacheinfo 100644,$blob,.gitattributes &&
386+
git check-attr --cached --all trailing >actual 2>err &&
387+
echo "warning: ignoring overly long attributes line 1" >expect &&
388+
test_cmp expect err &&
389+
test_must_be_empty actual
390+
'
391+
392+
test_expect_success EXPENSIVE 'large attributes file ignored in index' '
393+
test_when_finished "git update-index --remove .gitattributes" &&
394+
blob=$(dd if=/dev/zero bs=101M count=1 2>/dev/null | git hash-object -w --stdin) &&
395+
git update-index --add --cacheinfo 100644,$blob,.gitattributes &&
396+
git check-attr --cached --all path >/dev/null 2>err &&
397+
echo "warning: ignoring overly large gitattributes blob ${SQ}.gitattributes${SQ}" >expect &&
398+
test_cmp expect err
399+
'
400+
342401
test_done

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