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Fix GH-19311: Unexpected path truncation of files contained in a tar file by PharData::extractTo() #19322

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Fix GH-19311: Unexpected path truncation of files contained in a tar file by PharData::extractTo() #19322

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33a591f
Rename phar number parser to avoid confusion
nielsdos Jul 30, 2025
6e1ee35
Unify all phar tar bail paths
nielsdos Jul 30, 2025
98df7e9
Parse PAX header and extract path
nielsdos Jul 30, 2025
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162 changes: 104 additions & 58 deletions ext/phar/tar.c
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Original file line number Diff line number Diff line change
Expand Up @@ -20,7 +20,7 @@
#include "phar_internal.h"
#include "ext/standard/php_string.h" /* For php_stristr() */

static uint32_t phar_tar_number(const char *buf, size_t len) /* {{{ */
static uint32_t phar_tar_oct_number(const char *buf, size_t len) /* {{{ */
{
uint32_t num = 0;
size_t i = 0;
Expand Down Expand Up @@ -103,7 +103,7 @@ static uint32_t phar_tar_checksum(char *buf, size_t len) /* {{{ */
bool phar_is_tar(char *buf, char *fname) /* {{{ */
{
tar_header *header = (tar_header *) buf;
uint32_t checksum = phar_tar_number(header->checksum, sizeof(header->checksum));
uint32_t checksum = phar_tar_oct_number(header->checksum, sizeof(header->checksum));
bool is_tar;
char save[sizeof(header->checksum)], *bname;

Expand Down Expand Up @@ -213,6 +213,8 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
int last_was_longlink = 0;
size_t linkname_len;

zend_string *filename_pax_override = NULL;

if (error) {
*error = NULL;
}
Expand Down Expand Up @@ -255,7 +257,7 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch

pos = php_stream_tell(fp);
hdr = (tar_header*) buf;
sum1 = phar_tar_number(hdr->checksum, sizeof(hdr->checksum));
sum1 = phar_tar_oct_number(hdr->checksum, sizeof(hdr->checksum));
if (sum1 == 0 && phar_tar_checksum(buf, sizeof(buf)) == 0) {
break;
}
Expand All @@ -272,15 +274,81 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
}

size = entry.uncompressed_filesize = entry.compressed_filesize =
phar_tar_number(hdr->size, sizeof(hdr->size));
phar_tar_oct_number(hdr->size, sizeof(hdr->size));

/* skip global/file headers (pax) */
if (!old && (hdr->typeflag == TAR_GLOBAL_HDR || hdr->typeflag == TAR_FILE_HDR)) {
if (!old && hdr->typeflag == TAR_GLOBAL_HDR) {
size = (size+511)&~511;
goto next;
}

if (((!old && hdr->prefix[0] == 0) || old) && zend_strnlen(hdr->name, 100) == sizeof(".phar/signature.bin")-1 && !strncmp(hdr->name, ".phar/signature.bin", sizeof(".phar/signature.bin")-1)) {
/* Process file pax header */
if (!old && hdr->typeflag == TAR_FILE_HDR) {
size = (size + 511) & ~511;

char *pax_data = emalloc(size);

if (UNEXPECTED(php_stream_read(fp, pax_data, size) != size)) {
efree(pax_data);
goto truncated;
}

/* TODO: should this be usable multiple times? */
if (filename_pax_override) {
zend_string_release(filename_pax_override);
filename_pax_override = NULL;
}

char *ptr = pax_data;
const char *pax_data_end = pax_data + size;
while (ptr < pax_data_end) {
/* Format: "%d %s=%s\n" */

char *line_end = memchr(ptr, '\n', pax_data_end - ptr);
if (!line_end) {
break;
}

char *blank = memchr(ptr, ' ', line_end - ptr);
if (!blank) {
break;
}
*blank = '\0';
size_t kv_size = strtoull(ptr, NULL, 10);
if (kv_size != line_end - ptr + 1) {
break;
}

/* Check for known keys */
const char *key = blank + 1;
const char *equals = memchr(key, '=', line_end - key);
if (!equals) {
break;
}
size_t len = equals - key;
if (len == strlen("path") && memcmp(key, "path", strlen("path")) == 0) {
const char *filename_start = equals + 1;
size_t filename_pax_override_len = line_end - filename_start;
/* Ending '/' stripping */
if (filename_pax_override_len > 0 && filename_start[filename_pax_override_len - 1] == '/') {
filename_pax_override_len--;
}
filename_pax_override = zend_string_init(filename_start, filename_pax_override_len, myphar->is_persistent);
if (myphar->is_persistent) {
GC_MAKE_PERSISTENT_LOCAL(filename_pax_override);
}
}

ptr = line_end + 1;
}

efree(pax_data);

goto next_no_seek;
}

if ((filename_pax_override && zend_string_equals_literal(filename_pax_override, ".phar/signature.bin"))
|| (((!old && hdr->prefix[0] == 0) || old) && !strcmp(hdr->name, ".phar/signature.bin"))) {
zend_off_t curloc;
size_t sig_len;

Expand All @@ -289,6 +357,9 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
spprintf(error, 4096, "phar error: tar-based phar \"%s\" has signature that is larger than 511 bytes, cannot process", fname);
}
bail:
if (filename_pax_override) {
zend_string_release(filename_pax_override);
}
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
Expand Down Expand Up @@ -329,9 +400,7 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
if (error) {
spprintf(error, 4096, "phar error: \"%s\" is a corrupted tar file (truncated)", fname);
}
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}
}

Expand All @@ -341,13 +410,11 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
if (error) {
spprintf(error, 4096, "phar error: \"%s\" is a corrupted tar file (truncated)", fname);
}
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}

hdr = (tar_header*) buf;
sum1 = phar_tar_number(hdr->checksum, sizeof(hdr->checksum));
sum1 = phar_tar_oct_number(hdr->checksum, sizeof(hdr->checksum));

if (sum1 == 0 && phar_tar_checksum(buf, sizeof(buf)) == 0) {
break;
Expand All @@ -360,7 +427,10 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
goto bail;
}

if (!last_was_longlink && hdr->typeflag == 'L') {
if (filename_pax_override) {
entry.filename = filename_pax_override;
filename_pax_override = NULL;
} else if (!last_was_longlink && hdr->typeflag == 'L') {
last_was_longlink = 1;
/* support the ././@LongLink system for storing long filenames */

Expand All @@ -369,9 +439,7 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
if (error) {
spprintf(error, 4096, "phar error: \"%s\" is a corrupted tar file (invalid entry size)", fname);
}
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}
entry.filename = zend_string_alloc(entry.uncompressed_filesize, myphar->is_persistent);
if (myphar->is_persistent) {
Expand All @@ -385,9 +453,7 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
if (error) {
spprintf(error, 4096, "phar error: \"%s\" is a corrupted tar file (truncated)", fname);
}
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}

/* skip blank stuff */
Expand All @@ -400,9 +466,7 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
if (error) {
spprintf(error, 4096, "phar error: \"%s\" is a corrupted tar file (truncated)", fname);
}
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}

read = php_stream_read(fp, buf, sizeof(buf));
Expand All @@ -412,9 +476,7 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
if (error) {
spprintf(error, 4096, "phar error: \"%s\" is a corrupted tar file (truncated)", fname);
}
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}
continue;
} else if (!last_was_longlink && !old && hdr->prefix[0] != 0) {
Expand Down Expand Up @@ -474,17 +536,15 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
spprintf(error, 4096, "phar error: \"%s\" is a corrupted tar file (checksum mismatch of file \"%s\")", fname, ZSTR_VAL(entry.filename));
}
zend_string_release_ex(entry.filename, myphar->is_persistent);
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}

uint32_t entry_mode = phar_tar_number(hdr->mode, sizeof(hdr->mode));
uint32_t entry_mode = phar_tar_oct_number(hdr->mode, sizeof(hdr->mode));
entry.tar_type = ((old & (hdr->typeflag == '\0')) ? TAR_FILE : hdr->typeflag);
entry.offset = entry.offset_abs = pos; /* header_offset unused in tar */
entry.fp_type = PHAR_FP;
entry.flags = entry_mode & PHAR_ENT_PERM_MASK;
entry.timestamp = phar_tar_number(hdr->mtime, sizeof(hdr->mtime));
entry.timestamp = phar_tar_oct_number(hdr->mtime, sizeof(hdr->mtime));
entry.is_persistent = myphar->is_persistent;

if (old && entry.tar_type == TAR_FILE && S_ISDIR(entry_mode)) {
Expand All @@ -507,9 +567,7 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
spprintf(error, 4096, "phar error: \"%s\" is a corrupted tar file - hard link to non-existent file \"%.*s\"", fname, (int)linkname_len, hdr->linkname);
}
zend_string_release_ex(entry.filename, myphar->is_persistent);
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}
entry.link = estrndup(hdr->linkname, linkname_len);
} else if (entry.tar_type == TAR_SYMLINK) {
Expand All @@ -529,9 +587,7 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
if (error) {
spprintf(error, 4096, "phar error: tar-based phar \"%s\" has invalid metadata in magic file \"%s\"", fname, ZSTR_VAL(entry.filename));
}
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}
}

Expand All @@ -541,9 +597,7 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
if (error) {
spprintf(error, 4096, "phar error: tar-based phar \"%s\" has alias that is larger than 511 bytes, cannot process", fname);
}
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}

read = php_stream_read(fp, buf, size);
Expand All @@ -562,9 +616,7 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
spprintf(error, 4096, "phar error: invalid alias \"%s\" in tar-based phar \"%s\"", buf, fname);
}

php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}

actual_alias = pestrndup(buf, size, myphar->is_persistent);
Expand All @@ -576,9 +628,7 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
spprintf(error, 4096, "phar error: Unable to read alias from tar-based phar \"%s\"", fname);
}

php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}
}

Expand All @@ -588,13 +638,12 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
next:
/* this is not good enough - seek succeeds even on truncated tars */
php_stream_seek(fp, size, SEEK_CUR);
next_no_seek:
if ((uint32_t)php_stream_tell(fp) > totalsize) {
if (error) {
spprintf(error, 4096, "phar error: \"%s\" is a corrupted tar file (truncated)", fname);
}
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}
}

Expand All @@ -606,12 +655,11 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
read = php_stream_read(fp, buf, sizeof(buf));

if (read != sizeof(buf)) {
truncated:
if (error) {
spprintf(error, 4096, "phar error: \"%s\" is a corrupted tar file (truncated)", fname);
}
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}
}

Expand All @@ -623,12 +671,10 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch

/* ensure signature set */
if (!myphar->is_data && PHAR_G(require_hash) && !myphar->signature) {
php_stream_close(fp);
phar_destroy_phar_data(myphar);
if (error) {
spprintf(error, 0, "tar-based phar \"%s\" does not have a signature", fname);
}
return FAILURE;
goto bail;
}

myphar->fname = pestrndup(fname, fname_len, myphar->is_persistent);
Expand All @@ -655,9 +701,7 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
if (error) {
spprintf(error, 4096, "phar error: Unable to add tar-based phar \"%s\" to phar registry", fname);
}
php_stream_close(fp);
phar_destroy_phar_data(myphar);
return FAILURE;
goto bail;
}

myphar = actual;
Expand Down Expand Up @@ -706,6 +750,8 @@ zend_result phar_parse_tarfile(php_stream* fp, char *fname, size_t fname_len, ch
*pphar = myphar;
}

pefree(filename_pax_override, myphar->is_persistent);

return SUCCESS;
}
/* }}} */
Expand Down