diff options
Diffstat (limited to 'main/musl/1003-remove-ulimit-fiddling-from-setxid.patch')
| -rw-r--r-- | main/musl/1003-remove-ulimit-fiddling-from-setxid.patch | 72 |
1 files changed, 72 insertions, 0 deletions
diff --git a/main/musl/1003-remove-ulimit-fiddling-from-setxid.patch b/main/musl/1003-remove-ulimit-fiddling-from-setxid.patch new file mode 100644 index 0000000000..e66cdc3b7d --- /dev/null +++ b/main/musl/1003-remove-ulimit-fiddling-from-setxid.patch @@ -0,0 +1,72 @@ +From 1a2526fae0f3747ff7f60e60aa16b8148fd8ea07 Mon Sep 17 00:00:00 2001 +From: =?UTF-8?q?Timo=20Ter=C3=A4s?= <timo.teras@iki.fi> +Date: Thu, 24 Jul 2014 09:19:46 +0300 +Subject: [PATCH] remove ulimit fiddling from setxid + +It was only needed to workaround bugs in linux 3.1 and earlier. +Incidentally, the ulimit fiddling introduced another bug: it would +fail for non-root users. + +Additionally, this fixes updating c->err with atomic cas. +--- + src/unistd/setxid.c | 25 +++++++------------------ + 1 file changed, 7 insertions(+), 18 deletions(-) + +diff --git a/src/unistd/setxid.c b/src/unistd/setxid.c +index 2f651a1..6fcbc61 100644 +--- a/src/unistd/setxid.c ++++ b/src/unistd/setxid.c +@@ -1,7 +1,7 @@ + #include <unistd.h> + #include <errno.h> +-#include <sys/resource.h> + #include "syscall.h" ++#include "atomic.h" + #include "libc.h" + + struct ctx { +@@ -9,35 +9,24 @@ struct ctx { + int nr, rlim, err; + }; + +-/* We jump through hoops to eliminate the possibility of partial failures. */ ++/* This is not reliable on kernels earlier than 3.1, as set*uid can ++ * fail with EAGAIN if ulimit is exceeded. If that happens, the process ++ * is left in inconsistent state. */ + + int __setrlimit(int, const struct rlimit *); + + static void do_setxid(void *p) + { + struct ctx *c = p; ++ int r; + if (c->err) return; +- if (c->rlim && c->id >= 0 && c->id != getuid()) { +- struct rlimit inf = { RLIM_INFINITY, RLIM_INFINITY }, old; +- getrlimit(RLIMIT_NPROC, &old); +- if ((c->err = -__setrlimit(RLIMIT_NPROC, &inf)) && libc.threads_minus_1) +- return; +- c->err = -__syscall(c->nr, c->id, c->eid, c->sid); +- __setrlimit(RLIMIT_NPROC, &old); +- return; +- } +- c->err = -__syscall(c->nr, c->id, c->eid, c->sid); ++ r = __syscall(c->nr, c->id, c->eid, c->sid); ++ if (r) a_cas(&c->err, 0, -r); + } + + int __setxid(int nr, int id, int eid, int sid) + { + struct ctx c = { .nr = nr, .id = id, .eid = eid, .sid = sid }; +- switch (nr) { +- case SYS_setuid: +- case SYS_setreuid: +- case SYS_setresuid: +- c.rlim = 1; +- } + __synccall(do_setxid, &c); + if (c.err) { + errno = c.err; +-- +2.0.2 + |