Happened today to @Addshore while SWATting. Looks like some directories under objects for /srv/mediawiki-staging/php-1.31.0-wmf.20 git repo don't have group write permissions, thus failing a deploy.
I manually fixed tin with chmod -R g+w /srv/mediawiki-staging/php-1.31.0-wmf.20/.git though it would be nice to know what caused this.
Looking at the list of directories with wrong perms there seem to be a pattern:
naos:/srv/mediawiki-staging/php-1.31.0-wmf.20/.git$ find . ! -perm -g+w -type d -ls 2884346 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/08 2884391 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/3d 2884374 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/2a 2884483 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/a3 2884506 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/c0 2884470 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/90 2884401 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/45 2884523 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:00 ./objects/ec 2884492 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/ab 2884422 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/5b 2884458 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/7f 2884505 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/bc 2884376 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/2c 2884466 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/88 2884369 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./objects/26 2884513 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/d5 2884488 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/a8 2884526 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/f1 2884451 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./objects/79 2884487 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/a6 2884354 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/14 2884494 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/ac 2884393 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/3e 2884426 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/5e 2884468 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./objects/8a 2884474 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/97 2884479 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/9e 2884521 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/e8 2884460 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/80 2884522 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/eb 2884433 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:00 ./objects/60 2884472 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/95 2884372 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/28 2884519 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/e3 2884412 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/4f 2884414 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/53 2884464 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/86 2884342 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/01 2884348 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/0c 2884396 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/3f 2884383 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./objects/34 2884442 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/70 2884362 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/1b 2884477 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./objects/9c 2884420 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./objects/59 2884500 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/b5 2884345 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/07 2884424 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/5c 2884446 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/74 2884462 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/82 2884518 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/df 2884435 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/63 2884431 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/5f 2884508 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/c7 2884528 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/fc 2884380 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/32 2884516 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/dc 2884525 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/f0 2884398 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/44 2884350 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/0e 2884358 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/18 2884360 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/1a 2884403 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/47 2884490 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/a9 2884509 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/c9 2884481 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./objects/a2 2884517 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/dd 2884502 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/ba 2884378 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/30 2884507 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/c5 2884496 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/af 2884385 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./objects/38 2884453 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/7a 2884512 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/d1 2884529 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/ff 2884524 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/ef 2884387 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/3a 2884449 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/78 2884514 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/d7 2884352 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./objects/10 2884498 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/b1 2884520 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/e4 2884504 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/bb 2884410 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/4d 2884527 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/f2 2884418 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./objects/58 2884510 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/ca 2884455 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/7b 2884365 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/20 2884437 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/64 2884389 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/3b 2884511 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/cc 2884408 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/4c 2884344 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/04 2884485 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/a5 2884367 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/25 2884356 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/17 2884444 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/71 2884515 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/db 2884416 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:00 ./objects/54 2884439 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/6f 2884343 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 21:44 ./objects/02 2884406 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:00 ./objects/4a 6160396 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./modules/extensions/TextExtracts/refs/remotes/origin/wmf 2884284 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./modules/extensions/TextExtracts/objects/2c 2884340 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./modules/extensions/TextExtracts/objects/be 2884298 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./modules/extensions/TextExtracts/objects/58 2884341 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./modules/extensions/TextExtracts/objects/fe 2884292 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./modules/extensions/TextExtracts/objects/4a 6160395 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./modules/extensions/TextExtracts/logs/refs/remotes/origin/wmf 6160394 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./modules/extensions/MobileFrontend/refs/remotes/origin/wmf 6160392 4 drwxr-sr-x 2 tgr wikidev 4096 Feb 9 22:37 ./modules/extensions/MobileFrontend/logs/refs/remotes/origin/wmf naos:/srv/mediawiki-staging/php-1.31.0-wmf.20/.git$
Perhaps an umask too restrictive.