From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on inbox.vuxu.org X-Spam-Level: X-Spam-Status: No, score=-1.2 required=5.0 tests=DKIM_INVALID,DKIM_SIGNED, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,RCVD_IN_DNSWL_MED, RCVD_IN_MSPIKE_H3,RCVD_IN_MSPIKE_WL,T_SCC_BODY_TEXT_LINE,URIBL_BLACK autolearn=ham autolearn_force=no version=3.4.4 Received: from second.openwall.net (second.openwall.net [193.110.157.125]) by inbox.vuxu.org (Postfix) with SMTP id 4F61321F9F for ; Thu, 18 Jan 2024 01:06:08 +0100 (CET) Received: (qmail 7761 invoked by uid 550); 18 Jan 2024 00:04:15 -0000 Mailing-List: contact musl-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Reply-To: musl@lists.openwall.com Received: (qmail 7723 invoked from network); 18 Jan 2024 00:04:15 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=rtone.fr; s=google; t=1705536355; x=1706141155; darn=lists.openwall.com; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:from:to:cc:subject:date:message-id:reply-to; bh=hRLCnFPOVX8/1Y9MwY3LrCIRIM98FEgC+GeyZtvF0GI=; b=WSTIE0/tpt7IZ5C08rMBaQ47J688Gd3icw/cxm1NuRNoR1teEjtCpwicS6GGm3bH7Q 9m5EIW8/ukcH4RZElUbt6p1ESlhiKvbf4lMG63fDRnPacFPc21CFYWxrYc75nxJojQC+ 7ipEcPWlupwjkBqOsQlFPNyZhNrgLhIcWVMNI= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1705536355; x=1706141155; h=content-transfer-encoding:mime-version:message-id:date:subject:cc :to:from:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=hRLCnFPOVX8/1Y9MwY3LrCIRIM98FEgC+GeyZtvF0GI=; b=ELwwiXAv3P37umJcFU2gmgpzhiJ3N6SaQIQXQOUEDgx9P3IbRQskO0KHzChVgTbFx1 BbG5wn73QmRrtG+biXv5tbRgqCDPW1I7FwYo1Rk743FlWYmAKZtC3EPwy9tRzx7Fyv4D LkZS3PdNGAgfYuYzcjcGprp6nWJxUIDF9cISTnED0anT2LnP7YtiQ3MlWsvWKEi1O0KY tvVsTAYH7w+pOl3SKPBL2ycpNWZHE5gzmuaLARbNaEIfEQryCnHKY9jxxXyZj9ZX2agu fslo1eGPv9VqwZBOo558fgZNhatOswO0JDIqVkOABsV7EwKuHjveulGVIPab0rdQYnu7 z9Ow== X-Gm-Message-State: AOJu0Yyw3WmXQfbK80qR4FfX3zB08s1EaOSn1J0BpEHibazCu2BszMwR Kmdrpekjew3rAPdvCfXO7aU6kMReAv/zfmLDh4wmbKgUI9M= X-Google-Smtp-Source: AGHT+IFwIidjdpD6EBngVOKBPqEyV00SGsmSVw4OzEsLHgdS2Y69FrFspoW4i9UQZXT5yGkT8Iip4Q== X-Received: by 2002:a1c:7c0a:0:b0:40e:9002:a777 with SMTP id x10-20020a1c7c0a000000b0040e9002a777mr51699wmc.183.1705536355172; Wed, 17 Jan 2024 16:05:55 -0800 (PST) From: =?UTF-8?q?Ga=C3=ABl=20PORTAY?= To: musl@lists.openwall.com Cc: gael.portay@rtone.fr Date: Thu, 18 Jan 2024 01:05:37 +0100 Message-ID: <20240118000540.369070-1-gael.portay@rtone.fr> X-Mailer: git-send-email 2.43.0 MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Subject: [musl] [PATCH 0/3] use new SYS_fchmodat2 syscall to implement fchmodat with flags hello, this patch serie adds the syscall SYS_fchmodat2 to implement fchmodat(). it has landed in linux v6.6. the first patch remove the spurious flag argument from the syscall SYS_fchmodat (linux lacks for that argument actually). the second patch defines the syscall itself in headers. the third patch uses the syscall SYS_fchmodat2 to implement fchmodat() if flags are passed. the same way the syscall SYS_faccessat2 was used to implement faccessat() with flags. it wat tested locally on x86_64 (only), with a dummy test-fchmodat.c. here is what strace says if no flags are passed: gportay@archlinux ~/src/musl $ strace ./lib/libc.so ./test-fchmodat . file 0664 0 execve("./lib/libc.so", ["./lib/libc.so", "./test-fchmodat", ".", "file", "0664", "0"], 0x7ffc172ccc68 /* 34 vars */) = 0 arch_prctl(ARCH_SET_FS, 0x765732cf7ba8) = 0 set_tid_address(0x765732cf8018) = 367709 open("./test-fchmodat", O_RDONLY|O_LARGEFILE) = 3 read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\260\20\0\0\0\0\0\0"..., 960) = 960 mmap(NULL, 20480, PROT_READ, MAP_PRIVATE, 3, 0) = 0x765732c58000 mmap(0x765732c59000, 4096, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED, 3, 0x1000) = 0x765732c59000 mmap(0x765732c5a000, 4096, PROT_READ, MAP_PRIVATE|MAP_FIXED, 3, 0x2000) = 0x765732c5a000 mmap(0x765732c5b000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED, 3, 0x2000) = 0x765732c5b000 close(3) = 0 brk(NULL) = 0x5555568a6000 brk(0x5555568a8000) = 0x5555568a8000 mmap(0x5555568a6000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x5555568a6000 mprotect(0x765732cf4000, 4096, PROT_READ) = 0 mprotect(0x765732c5b000, 4096, PROT_READ) = 0 fchmodat(AT_FDCWD, "file", 0664) = 0 exit_group(0) = ? +++ exited with 0 +++ it uses the syscall fchmodat. and what strace says if AT_SYMLINK_NOFOLLOW is passed: gportay@archlinux ~/src/musl $ strace ./lib/libc.so ./test-fchmodat . file 0664 0x100 execve("./lib/libc.so", ["./lib/libc.so", "./test-fchmodat", ".", "file", "0664", "0x100"], 0x7ffcd7228278 /* 34 vars */) = 0 arch_prctl(ARCH_SET_FS, 0x7318d8907ba8) = 0 set_tid_address(0x7318d8908018) = 367715 open("./test-fchmodat", O_RDONLY|O_LARGEFILE) = 3 read(3, "\177ELF\2\1\1\0\0\0\0\0\0\0\0\0\3\0>\0\1\0\0\0\260\20\0\0\0\0\0\0"..., 960) = 960 mmap(NULL, 20480, PROT_READ, MAP_PRIVATE, 3, 0) = 0x7318d8868000 mmap(0x7318d8869000, 4096, PROT_READ|PROT_EXEC, MAP_PRIVATE|MAP_FIXED, 3, 0x1000) = 0x7318d8869000 mmap(0x7318d886a000, 4096, PROT_READ, MAP_PRIVATE|MAP_FIXED, 3, 0x2000) = 0x7318d886a000 mmap(0x7318d886b000, 8192, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_FIXED, 3, 0x2000) = 0x7318d886b000 close(3) = 0 brk(NULL) = 0x55555563d000 brk(0x55555563f000) = 0x55555563f000 mmap(0x55555563d000, 4096, PROT_NONE, MAP_PRIVATE|MAP_FIXED|MAP_ANONYMOUS, -1, 0) = 0x55555563d000 mprotect(0x7318d8904000, 4096, PROT_READ) = 0 mprotect(0x7318d886b000, 4096, PROT_READ) = 0 fchmodat2(AT_FDCWD, "file", 0664, AT_SYMLINK_NOFOLLOW) = 0 exit_group(0) = ? +++ exited with 0 +++ it uses the syscall fchmodat2! note: I fails to subscribe to mailing list; please make sure I receive a copy of any response, I am in cc; sorry for the inconvenience. I hope I did everything correctly. regards, Gaël PORTAY (3): remove flag argument from fchmodat syscall bits/syscall.h: add __NR_fchmodat2 from linux v6.6 use new SYS_fchmodat2 syscall to implement fchmodat with flags arch/arm/bits/syscall.h.in | 1 + arch/i386/bits/syscall.h.in | 1 + arch/m68k/bits/syscall.h.in | 1 + arch/microblaze/bits/syscall.h.in | 1 + arch/mips/bits/syscall.h.in | 1 + arch/mips64/bits/syscall.h.in | 1 + arch/mipsn32/bits/syscall.h.in | 1 + arch/or1k/bits/syscall.h.in | 1 + arch/powerpc/bits/syscall.h.in | 1 + arch/powerpc64/bits/syscall.h.in | 1 + arch/riscv64/bits/syscall.h.in | 1 + arch/s390x/bits/syscall.h.in | 1 + arch/sh/bits/syscall.h.in | 1 + arch/x32/bits/syscall.h.in | 1 + arch/x86_64/bits/syscall.h.in | 1 + src/stat/fchmodat.c | 7 ++++++- 16 files changed, 21 insertions(+), 1 deletion(-) -- 2.43.0