diff options
author | Stefano Brivio <sbrivio@redhat.com> | 2024-08-20 00:24:13 +0200 |
---|---|---|
committer | Stefano Brivio <sbrivio@redhat.com> | 2024-08-21 12:03:48 +0200 |
commit | 6e9ecf57410bd27cc48785125767f65e0455c76a (patch) | |
tree | b4dd396f5108247a65222c4bd31d26e738b9cf1b | |
parent | 7291b70ba7fb2c5ba11e00381d645a6c771881d9 (diff) | |
download | passt-6e9ecf57410bd27cc48785125767f65e0455c76a.tar passt-6e9ecf57410bd27cc48785125767f65e0455c76a.tar.gz passt-6e9ecf57410bd27cc48785125767f65e0455c76a.tar.bz2 passt-6e9ecf57410bd27cc48785125767f65e0455c76a.tar.lz passt-6e9ecf57410bd27cc48785125767f65e0455c76a.tar.xz passt-6e9ecf57410bd27cc48785125767f65e0455c76a.tar.zst passt-6e9ecf57410bd27cc48785125767f65e0455c76a.zip |
util: Provide own version of close_range(), and no-op fallback
musl, as of 1.2.5, and glibc < 2.34 don't ship a (trivial)
close_range() implementation. This will probably be added to musl
soon, by the way:
https://www.openwall.com/lists/musl/2024/08/01/9
Add a weakly-aliased implementation, if it's supported by the kernel.
If it's not supported (< 5.9), use a no-op fallback. Looping over 2^31
file descriptors calling close() on them is probably not a good idea.
Reported-by: lemmi <lemmi@nerd2nerd.org>
Signed-off-by: Stefano Brivio <sbrivio@redhat.com>
Reviewed-by: David Gibson <david@gibson.dropbear.id.au>
-rw-r--r-- | util.h | 22 |
1 files changed, 22 insertions, 0 deletions
@@ -14,6 +14,9 @@ #include <string.h> #include <signal.h> #include <arpa/inet.h> +#include <unistd.h> +#include <sys/syscall.h> +#include <linux/close_range.h> #include "log.h" @@ -159,6 +162,25 @@ struct ctx; /* cppcheck-suppress funcArgNamesDifferent */ __attribute__ ((weak)) int ffsl(long int i) { return __builtin_ffsl(i); } + +#ifdef CLOSE_RANGE_UNSHARE /* Linux kernel >= 5.9 */ +/* glibc < 2.34 and musl as of 1.2.5 need these */ +#ifndef SYS_close_range +#define SYS_close_range 436 +#endif +__attribute__ ((weak)) +/* cppcheck-suppress funcArgNamesDifferent */ +int close_range(unsigned int first, unsigned int last, int flags) { + return syscall(SYS_close_range, first, last, flags); +} +#else +/* No reasonable fallback option */ +/* cppcheck-suppress funcArgNamesDifferent */ +int close_range(unsigned int first, unsigned int last, int flags) { + return 0; +} +#endif + int sock_l4_sa(const struct ctx *c, enum epoll_type type, const void *sa, socklen_t sl, const char *ifname, bool v6only, uint32_t data); |