5d33dbb67
Denys Vlasenko
2026-01-23
Subject
httpd: smarter handling of CGI's "Status: " header
Binary
No binary (build failed)
Architecture & Compiler Flags
gcc -Wp,-MD,applets/.usage.d -Wall -Wstrict-prototypes -O2 -fomit-frame-pointer -Iinclude -Iinclude -o applets/usage applets/usage.c
Build Log
(log yok)
Commit Diff GitHub →
networking/httpd.c+13 -10
| @@ -1521,7 +1521,8 @@ static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post | |
| * CGI may output a few first bytes and then wait | |
| * for POSTDATA without closing stdout. | |
| * With full_read we may wait here forever. */ | |
| - | count = safe_read(fromCgi_rd, iobuf + out_cnt, IOBUF_SIZE); |
| + | count = safe_read(fromCgi_rd, iobuf + out_cnt, IOBUF_SIZE - 8); |
| + | // "- 8" is important, out_cnt can be up to 7 |
| if (count <= 0) { | |
| /* EOF (or error, and out_cnt=0..7 | |
| * send "HTTP/1.1 200 OK\r\n", then send received 0..7 bytes */ | |
| @@ -1534,19 +1535,21 @@ static NOINLINE void cgi_io_loop_and_exit(int fromCgi_rd, int toCgi_wr, int post | |
| if (out_cnt >= 8) { | |
| //FIXME: "Status: " is not required to be the first header! It can be anywhere! | |
| //FIXME: many servers also check "Location: ". If it exists but "Status: " does _not_, "302 Found" is assumed instead of "200 OK". | |
| + | uint64_t str8 = *(uint64_t*)iobuf; |
| /* "Status" header format is: "Status: 302 Redirected\r\n" */ | |
| //if (memcmp(iobuf, "Status: ", 8) == 0) | |
| - | if (*(uint64_t*)iobuf == PACK64_LITERAL_STR("Status: ")) { |
| - | /* send "HTTP/1.1 " */ |
| - | if (full_write(STDOUT_FILENO, HTTP_200, 9) != 9) |
| - | break; |
| - | /* skip "Status: " (including space, sending "HTTP/1.1 NNN" is wrong) */ |
| - | out_cnt -= 8; |
| - | memmove(iobuf, iobuf + 8, out_cnt); |
| + | if (str8 == PACK64_LITERAL_STR("Status: ")) { |
| + | /* Replace "Status: " */ |
| + | /* with "HTTP/1.1 " */ |
| + | memmove(iobuf + 1, iobuf, out_cnt); |
| + | out_cnt += 1; |
| + | memcpy(iobuf, HTTP_200, 9); |
| } | |
| //NB: Apache has no such autodetection. It always adds its own HTTP/1.x header, | |
| //unless the CGI name starts with "nph-", in which case it passes its output verbatim to network. | |
| - | else if (memcmp(iobuf, HTTP_200, 8) != 0) { /* Did CGI send "HTTP/1.1"? */ |
| + | else /* Did CGI send "HTTP/1.1"? */ |
| + | //if (memcmp(iobuf, HTTP_200, 8) != 0) |
| + | if (str8 == PACK64_LITERAL_STR(HTTP_200)) { |
| write_HTTP_200_OK: | |
| /* no, send "HTTP/1.1 200 OK\r\n" ourself */ | |
| if (full_write(STDOUT_FILENO, HTTP_200, sizeof(HTTP_200)-1) != sizeof(HTTP_200)-1) | |
| @@ -2475,7 +2478,7 @@ static void handle_incoming_and_exit(const len_and_sockaddr *fromAddr) | |
| /* Log it */ | |
| if (VERBOSE_2) | |
| - | bb_error_msg("url:%s", urlcopy); |
| + | bb_error_msg("%s %s", prequest, urlcopy); |
| tptr = urlcopy; | |
| while ((tptr = strchr(tptr + 1, '/')) != NULL) { | |