From patchwork Fri Apr 26 16:20:14 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: =?utf-8?q?Christian_G=C3=B6ttsche?= X-Patchwork-Id: 13645070 Received: from server02.seltendoof.de (server02.seltendoof.de [168.119.48.163]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 553A244377; Fri, 26 Apr 2024 16:32:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=168.119.48.163 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714149131; cv=none; b=cUuzck/VTg0rfEeoLZB3TkspI5t0ive9+o9d/ScsswgusBcNSfE5tyHylHDsMcWaaOi88L7TEHPEUomeWDQyyYrscNjWFdvjXLZhcWqiUtIJ7YtTV/p5WC24uo/7oCNWjpdtgQcg4xrP7a4cirP6xxCuyDVEDX7aqf3S9SydYJQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1714149131; c=relaxed/simple; bh=pwUbf0CJzfzTif6FLawW1Ntu8PXv55PrXwYHbALlKBY=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version:Content-Type; b=oeekLRsEUuMb7WoZOZc+LdaaDF4xHIhDw0wxggYmqL98wmLioVmSIa8rr6MnA49kU2RzyDZhHpDGJZUyZ3vqBJiOu1XWnyBMnKpFYKrkvtwcrybmlAWaVV00iavaDR344T7oDlYv3KbQTQZ0ul+di5wHW82j6BMhw5OeKGiQI3o= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=seltendoof.de; spf=pass smtp.mailfrom=seltendoof.de; dkim=pass (2048-bit key) header.d=seltendoof.de header.i=@seltendoof.de header.b=NNLzwoGz; arc=none smtp.client-ip=168.119.48.163 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=seltendoof.de Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=seltendoof.de Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=seltendoof.de header.i=@seltendoof.de header.b="NNLzwoGz" From: =?utf-8?q?Christian_G=C3=B6ttsche?= DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=seltendoof.de; s=2023072701; t=1714148461; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=z5JmHtkLiQ57ZBKXVrmaKQ/XqCOuY5zjpycUDX8wsGM=; b=NNLzwoGzbnLH2jZw966e6jSsnimzqSiNByTgO/pFKf0ZK61KJa0cuDMUYUEuU8US4QgmN1 ybO2yMl69Hwe51SIfxWCrbXu60CN2cfiBzGtAva23gNgdHEi2vRz00QY3rtH5c3VzczrL6 lG8hFYIHVmeYNCtTQKvguCpepTLU/cS8krVayViHJao1raPqNEXp6e4WUtWi+SS2oq9fL/ +kgF2MbSrJahOa0C+8gmy0je2nALPVdg1tKH4kx0Ud44+qG32mdg2p3nEd6QaiOxcBeYNJ 4GYAHh4NZbzeGImOZL0DWJJTIuVlGAuN+utdWTECAZwe/yvoTgA49SXphmXdcg== To: cgzones@googlemail.com Cc: x86@kernel.org, linux-alpha@vger.kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-mips@vger.kernel.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-fsdevel@vger.kernel.org, audit@vger.kernel.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, linux-security-module@vger.kernel.org, selinux@vger.kernel.org, Richard Henderson , Ivan Kokshaysky , Matt Turner , Russell King , Catalin Marinas , Will Deacon , Geert Uytterhoeven , Michal Simek , Thomas Bogendoerfer , "James E.J. Bottomley" , Helge Deller , Michael Ellerman , Nicholas Piggin , Christophe Leroy , "Aneesh Kumar K.V" , "Naveen N. Rao" , Heiko Carstens , Vasily Gorbik , Alexander Gordeev , Christian Borntraeger , Sven Schnelle , Yoshinori Sato , Rich Felker , John Paul Adrian Glaubitz , "David S. Miller" , Andreas Larsson , Andy Lutomirski , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Chris Zankel , Max Filippov , Alexander Viro , Christian Brauner , Jan Kara , Paul Moore , Eric Paris , Arnd Bergmann , Jens Axboe , Pavel Begunkov , Peter Zijlstra , Sohil Mehta , Palmer Dabbelt , Miklos Szeredi , Nhat Pham , Casey Schaufler , Florian Fainelli , Kees Cook , Rick Edgecombe , Mark Rutland , io-uring@vger.kernel.org Subject: [PATCH v3 2/2] fs/xattr: add *at family syscalls Date: Fri, 26 Apr 2024 18:20:14 +0200 Message-ID: <20240426162042.191916-1-cgoettsche@seltendoof.de> Reply-To: cgzones@googlemail.com Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 From: Christian Göttsche Add the four syscalls setxattrat(), getxattrat(), listxattrat() and removexattrat(). Those can be used to operate on extended attributes, especially security related ones, either relative to a pinned directory or on a file descriptor without read access, avoiding a /proc//fd/ detour, requiring a mounted procfs. One use case will be setfiles(8) setting SELinux file contexts ("security.selinux") without race conditions and without a file descriptor opened with read access requiring SELinux read permission. Use the do_{name}at() pattern from fs/open.c. Pass the value of the extended attribute, its length, and for setxattrat(2) the command (XATTR_CREATE or XATTR_REPLACE) via an added struct xattr_args to not exceed six syscall arguments and not merging the AT_* and XATTR_* flags. Signed-off-by: Christian Göttsche CC: x86@kernel.org CC: linux-alpha@vger.kernel.org CC: linux-kernel@vger.kernel.org CC: linux-arm-kernel@lists.infradead.org CC: linux-ia64@vger.kernel.org CC: linux-m68k@lists.linux-m68k.org CC: linux-mips@vger.kernel.org CC: linux-parisc@vger.kernel.org CC: linuxppc-dev@lists.ozlabs.org CC: linux-s390@vger.kernel.org CC: linux-sh@vger.kernel.org CC: sparclinux@vger.kernel.org CC: linux-fsdevel@vger.kernel.org CC: audit@vger.kernel.org CC: linux-arch@vger.kernel.org CC: linux-api@vger.kernel.org CC: linux-security-module@vger.kernel.org CC: selinux@vger.kernel.org Reviewed-by: Arnd Bergmann --- v3: - pass value, size and xattr_flags via new struct xattr_args to split AT_* and XATTR_* flags v2: https://lore.kernel.org/lkml/20230511150802.737477-1-cgzones@googlemail.com/ - squash syscall introduction and wire up commits - add AT_XATTR_CREATE and AT_XATTR_REPLACE constants v1 discussion: https://lore.kernel.org/all/20220830152858.14866-2-cgzones@googlemail.com/ Previous approach ("f*xattr: allow O_PATH descriptors"): https://lore.kernel.org/all/20220607153139.35588-1-cgzones@googlemail.com/ --- arch/alpha/kernel/syscalls/syscall.tbl | 4 + arch/arm/tools/syscall.tbl | 4 + arch/arm64/include/asm/unistd.h | 2 +- arch/arm64/include/asm/unistd32.h | 8 ++ arch/m68k/kernel/syscalls/syscall.tbl | 4 + arch/microblaze/kernel/syscalls/syscall.tbl | 4 + arch/mips/kernel/syscalls/syscall_n32.tbl | 4 + arch/mips/kernel/syscalls/syscall_n64.tbl | 4 + arch/mips/kernel/syscalls/syscall_o32.tbl | 4 + arch/parisc/kernel/syscalls/syscall.tbl | 4 + arch/powerpc/kernel/syscalls/syscall.tbl | 4 + arch/s390/kernel/syscalls/syscall.tbl | 4 + arch/sh/kernel/syscalls/syscall.tbl | 4 + arch/sparc/kernel/syscalls/syscall.tbl | 4 + arch/x86/entry/syscalls/syscall_32.tbl | 4 + arch/x86/entry/syscalls/syscall_64.tbl | 4 + arch/xtensa/kernel/syscalls/syscall.tbl | 4 + fs/xattr.c | 128 ++++++++++++++++---- include/asm-generic/audit_change_attr.h | 6 + include/linux/syscalls.h | 10 ++ include/uapi/asm-generic/unistd.h | 12 +- include/uapi/linux/xattr.h | 6 + 22 files changed, 208 insertions(+), 24 deletions(-) diff --git a/arch/alpha/kernel/syscalls/syscall.tbl b/arch/alpha/kernel/syscalls/syscall.tbl index 8ff110826ce2..fdc11249f1b8 100644 --- a/arch/alpha/kernel/syscalls/syscall.tbl +++ b/arch/alpha/kernel/syscalls/syscall.tbl @@ -501,3 +501,7 @@ 569 common lsm_get_self_attr sys_lsm_get_self_attr 570 common lsm_set_self_attr sys_lsm_set_self_attr 571 common lsm_list_modules sys_lsm_list_modules +572 common setxattrat sys_setxattrat +573 common getxattrat sys_getxattrat +574 common listxattrat sys_listxattrat +575 common removexattrat sys_removexattrat diff --git a/arch/arm/tools/syscall.tbl b/arch/arm/tools/syscall.tbl index b6c9e01e14f5..22fbbcd8e2b5 100644 --- a/arch/arm/tools/syscall.tbl +++ b/arch/arm/tools/syscall.tbl @@ -475,3 +475,7 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules +462 common setxattrat sys_setxattrat +463 common getxattrat sys_getxattrat +464 common listxattrat sys_listxattrat +465 common removexattrat sys_removexattrat diff --git a/arch/arm64/include/asm/unistd.h b/arch/arm64/include/asm/unistd.h index 491b2b9bd553..f3a77719eb05 100644 --- a/arch/arm64/include/asm/unistd.h +++ b/arch/arm64/include/asm/unistd.h @@ -39,7 +39,7 @@ #define __ARM_NR_compat_set_tls (__ARM_NR_COMPAT_BASE + 5) #define __ARM_NR_COMPAT_END (__ARM_NR_COMPAT_BASE + 0x800) -#define __NR_compat_syscalls 462 +#define __NR_compat_syscalls 466 #endif #define __ARCH_WANT_SYS_CLONE diff --git a/arch/arm64/include/asm/unistd32.h b/arch/arm64/include/asm/unistd32.h index 7118282d1c79..963c999b8d2e 100644 --- a/arch/arm64/include/asm/unistd32.h +++ b/arch/arm64/include/asm/unistd32.h @@ -929,6 +929,14 @@ __SYSCALL(__NR_lsm_get_self_attr, sys_lsm_get_self_attr) __SYSCALL(__NR_lsm_set_self_attr, sys_lsm_set_self_attr) #define __NR_lsm_list_modules 461 __SYSCALL(__NR_lsm_list_modules, sys_lsm_list_modules) +#define __NR_setxattrat 462 +__SYSCALL(__NR_setxattrat, sys_setxattrat) +#define __NR_getxattrat 463 +__SYSCALL(__NR_getxattrat, sys_getxattrat) +#define __NR_listxattrat 464 +__SYSCALL(__NR_listxattrat, sys_listxattrat) +#define __NR_removexattrat 465 +__SYSCALL(__NR_removexattrat, sys_removexattrat) /* * Please add new compat syscalls above this comment and update diff --git a/arch/m68k/kernel/syscalls/syscall.tbl b/arch/m68k/kernel/syscalls/syscall.tbl index 7fd43fd4c9f2..7e8e2d9c3b81 100644 --- a/arch/m68k/kernel/syscalls/syscall.tbl +++ b/arch/m68k/kernel/syscalls/syscall.tbl @@ -461,3 +461,7 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules +462 common setxattrat sys_setxattrat +463 common getxattrat sys_getxattrat +464 common listxattrat sys_listxattrat +465 common removexattrat sys_removexattrat diff --git a/arch/microblaze/kernel/syscalls/syscall.tbl b/arch/microblaze/kernel/syscalls/syscall.tbl index b00ab2cabab9..7df7fc7c0528 100644 --- a/arch/microblaze/kernel/syscalls/syscall.tbl +++ b/arch/microblaze/kernel/syscalls/syscall.tbl @@ -467,3 +467,7 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules +462 common setxattrat sys_setxattrat +463 common getxattrat sys_getxattrat +464 common listxattrat sys_listxattrat +465 common removexattrat sys_removexattrat diff --git a/arch/mips/kernel/syscalls/syscall_n32.tbl b/arch/mips/kernel/syscalls/syscall_n32.tbl index 83cfc9eb6b88..07141274f9ff 100644 --- a/arch/mips/kernel/syscalls/syscall_n32.tbl +++ b/arch/mips/kernel/syscalls/syscall_n32.tbl @@ -400,3 +400,7 @@ 459 n32 lsm_get_self_attr sys_lsm_get_self_attr 460 n32 lsm_set_self_attr sys_lsm_set_self_attr 461 n32 lsm_list_modules sys_lsm_list_modules +462 n32 setxattrat sys_setxattrat +463 n32 getxattrat sys_getxattrat +464 n32 listxattrat sys_listxattrat +465 n32 removexattrat sys_removexattrat diff --git a/arch/mips/kernel/syscalls/syscall_n64.tbl b/arch/mips/kernel/syscalls/syscall_n64.tbl index 532b855df589..9773412f2812 100644 --- a/arch/mips/kernel/syscalls/syscall_n64.tbl +++ b/arch/mips/kernel/syscalls/syscall_n64.tbl @@ -376,3 +376,7 @@ 459 n64 lsm_get_self_attr sys_lsm_get_self_attr 460 n64 lsm_set_self_attr sys_lsm_set_self_attr 461 n64 lsm_list_modules sys_lsm_list_modules +462 n64 setxattrat sys_setxattrat +463 n64 getxattrat sys_getxattrat +464 n64 listxattrat sys_listxattrat +465 n64 removexattrat sys_removexattrat diff --git a/arch/mips/kernel/syscalls/syscall_o32.tbl b/arch/mips/kernel/syscalls/syscall_o32.tbl index f45c9530ea93..8b5fec66ec18 100644 --- a/arch/mips/kernel/syscalls/syscall_o32.tbl +++ b/arch/mips/kernel/syscalls/syscall_o32.tbl @@ -449,3 +449,7 @@ 459 o32 lsm_get_self_attr sys_lsm_get_self_attr 460 o32 lsm_set_self_attr sys_lsm_set_self_attr 461 o32 lsm_list_modules sys_lsm_list_modules +462 o32 setxattrat sys_setxattrat +463 o32 getxattrat sys_getxattrat +464 o32 listxattrat sys_listxattrat +465 o32 removexattrat sys_removexattrat diff --git a/arch/parisc/kernel/syscalls/syscall.tbl b/arch/parisc/kernel/syscalls/syscall.tbl index b236a84c4e12..b6ebcaadd460 100644 --- a/arch/parisc/kernel/syscalls/syscall.tbl +++ b/arch/parisc/kernel/syscalls/syscall.tbl @@ -460,3 +460,7 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules +462 common setxattrat sys_setxattrat +463 common getxattrat sys_getxattrat +464 common listxattrat sys_listxattrat +465 common removexattrat sys_removexattrat diff --git a/arch/powerpc/kernel/syscalls/syscall.tbl b/arch/powerpc/kernel/syscalls/syscall.tbl index 17173b82ca21..7e522a720e1a 100644 --- a/arch/powerpc/kernel/syscalls/syscall.tbl +++ b/arch/powerpc/kernel/syscalls/syscall.tbl @@ -548,3 +548,7 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules +462 common setxattrat sys_setxattrat +463 common getxattrat sys_getxattrat +464 common listxattrat sys_listxattrat +465 common removexattrat sys_removexattrat diff --git a/arch/s390/kernel/syscalls/syscall.tbl b/arch/s390/kernel/syscalls/syscall.tbl index 095bb86339a7..71afa1eb35fb 100644 --- a/arch/s390/kernel/syscalls/syscall.tbl +++ b/arch/s390/kernel/syscalls/syscall.tbl @@ -464,3 +464,7 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules sys_lsm_list_modules +462 common setxattrat sys_setxattrat sys_setxattrat +463 common getxattrat sys_getxattrat sys_getxattrat +464 common listxattrat sys_listxattrat sys_listxattrat +465 common removexattrat sys_removexattrat sys_removexattrat diff --git a/arch/sh/kernel/syscalls/syscall.tbl b/arch/sh/kernel/syscalls/syscall.tbl index 86fe269f0220..1fb0ac9f6c58 100644 --- a/arch/sh/kernel/syscalls/syscall.tbl +++ b/arch/sh/kernel/syscalls/syscall.tbl @@ -464,3 +464,7 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules +462 common setxattrat sys_setxattrat +463 common getxattrat sys_getxattrat +464 common listxattrat sys_listxattrat +465 common removexattrat sys_removexattrat diff --git a/arch/sparc/kernel/syscalls/syscall.tbl b/arch/sparc/kernel/syscalls/syscall.tbl index b23d59313589..bdd90010c8d1 100644 --- a/arch/sparc/kernel/syscalls/syscall.tbl +++ b/arch/sparc/kernel/syscalls/syscall.tbl @@ -507,3 +507,7 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules +462 common setxattrat sys_setxattrat +463 common getxattrat sys_getxattrat +464 common listxattrat sys_listxattrat +465 common removexattrat sys_removexattrat diff --git a/arch/x86/entry/syscalls/syscall_32.tbl b/arch/x86/entry/syscalls/syscall_32.tbl index 5f8591ce7f25..779dd1a9835d 100644 --- a/arch/x86/entry/syscalls/syscall_32.tbl +++ b/arch/x86/entry/syscalls/syscall_32.tbl @@ -466,3 +466,7 @@ 459 i386 lsm_get_self_attr sys_lsm_get_self_attr 460 i386 lsm_set_self_attr sys_lsm_set_self_attr 461 i386 lsm_list_modules sys_lsm_list_modules +462 i386 setxattrat sys_setxattrat +463 i386 getxattrat sys_getxattrat +464 i386 listxattrat sys_listxattrat +465 i386 removexattrat sys_removexattrat diff --git a/arch/x86/entry/syscalls/syscall_64.tbl b/arch/x86/entry/syscalls/syscall_64.tbl index 7e8d46f4147f..819c90564f82 100644 --- a/arch/x86/entry/syscalls/syscall_64.tbl +++ b/arch/x86/entry/syscalls/syscall_64.tbl @@ -383,6 +383,10 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules +462 common setxattrat sys_setxattrat +463 common getxattrat sys_getxattrat +464 common listxattrat sys_listxattrat +465 common removexattrat sys_removexattrat # # Due to a historical design error, certain syscalls are numbered differently diff --git a/arch/xtensa/kernel/syscalls/syscall.tbl b/arch/xtensa/kernel/syscalls/syscall.tbl index dd116598fb25..36bdfe759878 100644 --- a/arch/xtensa/kernel/syscalls/syscall.tbl +++ b/arch/xtensa/kernel/syscalls/syscall.tbl @@ -432,3 +432,7 @@ 459 common lsm_get_self_attr sys_lsm_get_self_attr 460 common lsm_set_self_attr sys_lsm_set_self_attr 461 common lsm_list_modules sys_lsm_list_modules +462 common setxattrat sys_setxattrat +463 common getxattrat sys_getxattrat +464 common listxattrat sys_listxattrat +465 common removexattrat sys_removexattrat diff --git a/fs/xattr.c b/fs/xattr.c index 941aab719da0..d45e83224a7c 100644 --- a/fs/xattr.c +++ b/fs/xattr.c @@ -655,21 +655,28 @@ setxattr(struct mnt_idmap *idmap, struct dentry *d, return error; } -static int path_setxattr(const char __user *pathname, +static int do_setxattrat(int dfd, const char __user *pathname, unsigned int at_flags, const char __user *name, const void __user *value, - size_t size, int flags, unsigned int lookup_flags) + size_t size, int xattr_flags) { struct path path; int error; + int lookup_flags; + if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0) + return -EINVAL; + + lookup_flags = (at_flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; + if (at_flags & AT_EMPTY_PATH) + lookup_flags |= LOOKUP_EMPTY; retry: - error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); + error = user_path_at(dfd, pathname, lookup_flags, &path); if (error) return error; error = mnt_want_write(path.mnt); if (!error) { error = setxattr(mnt_idmap(path.mnt), path.dentry, name, - value, size, flags); + value, size, xattr_flags); mnt_drop_write(path.mnt); } path_put(&path); @@ -680,18 +687,38 @@ static int path_setxattr(const char __user *pathname, return error; } +SYSCALL_DEFINE6(setxattrat, int, dfd, const char __user *, pathname, unsigned int, at_flags, + const char __user *, name, const struct xattr_args __user *, uargs, + size_t, usize) +{ + struct xattr_args args = {}; + int error; + + if (usize > PAGE_SIZE) + return -E2BIG; + if (usize < sizeof(args)) + return -EINVAL; + + error = copy_struct_from_user(&args, sizeof(args), uargs, usize); + if (error) + return error; + + return do_setxattrat(dfd, pathname, at_flags, name, (const void __user *)args.value, + args.size, args.flags); +} + SYSCALL_DEFINE5(setxattr, const char __user *, pathname, const char __user *, name, const void __user *, value, size_t, size, int, flags) { - return path_setxattr(pathname, name, value, size, flags, LOOKUP_FOLLOW); + return do_setxattrat(AT_FDCWD, pathname, 0, name, value, size, flags); } SYSCALL_DEFINE5(lsetxattr, const char __user *, pathname, const char __user *, name, const void __user *, value, size_t, size, int, flags) { - return path_setxattr(pathname, name, value, size, flags, 0); + return do_setxattrat(AT_FDCWD, pathname, AT_SYMLINK_NOFOLLOW, name, value, size, flags); } SYSCALL_DEFINE5(fsetxattr, int, fd, const char __user *, name, @@ -774,14 +801,22 @@ getxattr(struct mnt_idmap *idmap, struct dentry *d, return error; } -static ssize_t path_getxattr(const char __user *pathname, +static ssize_t do_getxattrat(int dfd, const char __user *pathname, unsigned int at_flags, const char __user *name, void __user *value, - size_t size, unsigned int lookup_flags) + size_t size) { struct path path; ssize_t error; + int lookup_flags; + + if ((at_flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0) + return -EINVAL; + + lookup_flags = (at_flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; + if (at_flags & AT_EMPTY_PATH) + lookup_flags |= LOOKUP_EMPTY; retry: - error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); + error = user_path_at(dfd, pathname, lookup_flags, &path); if (error) return error; error = getxattr(mnt_idmap(path.mnt), path.dentry, name, value, size); @@ -793,16 +828,37 @@ static ssize_t path_getxattr(const char __user *pathname, return error; } +SYSCALL_DEFINE6(getxattrat, int, dfd, const char __user *, pathname, unsigned int, at_flags, + const char __user *, name, struct xattr_args __user *, uargs, size_t, usize) +{ + struct xattr_args args = {}; + int error; + + if (usize > PAGE_SIZE) + return -E2BIG; + if (usize < sizeof(args)) + return -EINVAL; + + error = copy_struct_from_user(&args, sizeof(args), uargs, usize); + if (error) + return error; + + if (args.flags != 0) + return -EINVAL; + + return do_getxattrat(dfd, pathname, at_flags, name, (void __user *)args.value, args.size); +} + SYSCALL_DEFINE4(getxattr, const char __user *, pathname, const char __user *, name, void __user *, value, size_t, size) { - return path_getxattr(pathname, name, value, size, LOOKUP_FOLLOW); + return do_getxattrat(AT_FDCWD, pathname, 0, name, value, size); } SYSCALL_DEFINE4(lgetxattr, const char __user *, pathname, const char __user *, name, void __user *, value, size_t, size) { - return path_getxattr(pathname, name, value, size, 0); + return do_getxattrat(AT_FDCWD, pathname, AT_SYMLINK_NOFOLLOW, name, value, size); } SYSCALL_DEFINE4(fgetxattr, int, fd, const char __user *, name, @@ -852,13 +908,21 @@ listxattr(struct dentry *d, char __user *list, size_t size) return error; } -static ssize_t path_listxattr(const char __user *pathname, char __user *list, - size_t size, unsigned int lookup_flags) +static ssize_t do_listxattrat(int dfd, const char __user *pathname, char __user *list, + size_t size, int flags) { struct path path; ssize_t error; + int lookup_flags; + + if ((flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0) + return -EINVAL; + + lookup_flags = (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; + if (flags & AT_EMPTY_PATH) + lookup_flags |= LOOKUP_EMPTY; retry: - error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); + error = user_path_at(dfd, pathname, lookup_flags, &path); if (error) return error; error = listxattr(path.dentry, list, size); @@ -870,16 +934,22 @@ static ssize_t path_listxattr(const char __user *pathname, char __user *list, return error; } +SYSCALL_DEFINE5(listxattrat, int, dfd, const char __user *, pathname, char __user *, list, + size_t, size, int, flags) +{ + return do_listxattrat(dfd, pathname, list, size, flags); +} + SYSCALL_DEFINE3(listxattr, const char __user *, pathname, char __user *, list, size_t, size) { - return path_listxattr(pathname, list, size, LOOKUP_FOLLOW); + return do_listxattrat(AT_FDCWD, pathname, list, size, 0); } SYSCALL_DEFINE3(llistxattr, const char __user *, pathname, char __user *, list, size_t, size) { - return path_listxattr(pathname, list, size, 0); + return do_listxattrat(AT_FDCWD, pathname, list, size, AT_SYMLINK_NOFOLLOW); } SYSCALL_DEFINE3(flistxattr, int, fd, char __user *, list, size_t, size) @@ -898,7 +968,7 @@ SYSCALL_DEFINE3(flistxattr, int, fd, char __user *, list, size_t, size) /* * Extended attribute REMOVE operations */ -static long +static int removexattr(struct mnt_idmap *idmap, struct dentry *d, const char __user *name) { @@ -917,13 +987,21 @@ removexattr(struct mnt_idmap *idmap, struct dentry *d, return vfs_removexattr(idmap, d, kname); } -static int path_removexattr(const char __user *pathname, - const char __user *name, unsigned int lookup_flags) +static int do_removexattrat(int dfd, const char __user *pathname, + const char __user *name, int flags) { struct path path; int error; + int lookup_flags; + + if ((flags & ~(AT_SYMLINK_NOFOLLOW | AT_EMPTY_PATH)) != 0) + return -EINVAL; + + lookup_flags = (flags & AT_SYMLINK_NOFOLLOW) ? 0 : LOOKUP_FOLLOW; + if (flags & AT_EMPTY_PATH) + lookup_flags |= LOOKUP_EMPTY; retry: - error = user_path_at(AT_FDCWD, pathname, lookup_flags, &path); + error = user_path_at(dfd, pathname, lookup_flags, &path); if (error) return error; error = mnt_want_write(path.mnt); @@ -939,16 +1017,22 @@ static int path_removexattr(const char __user *pathname, return error; } +SYSCALL_DEFINE4(removexattrat, int, dfd, const char __user *, pathname, + const char __user *, name, int, flags) +{ + return do_removexattrat(dfd, pathname, name, flags); +} + SYSCALL_DEFINE2(removexattr, const char __user *, pathname, const char __user *, name) { - return path_removexattr(pathname, name, LOOKUP_FOLLOW); + return do_removexattrat(AT_FDCWD, pathname, name, 0); } SYSCALL_DEFINE2(lremovexattr, const char __user *, pathname, const char __user *, name) { - return path_removexattr(pathname, name, 0); + return do_removexattrat(AT_FDCWD, pathname, name, AT_SYMLINK_NOFOLLOW); } SYSCALL_DEFINE2(fremovexattr, int, fd, const char __user *, name) diff --git a/include/asm-generic/audit_change_attr.h b/include/asm-generic/audit_change_attr.h index 331670807cf0..cc840537885f 100644 --- a/include/asm-generic/audit_change_attr.h +++ b/include/asm-generic/audit_change_attr.h @@ -11,9 +11,15 @@ __NR_lchown, __NR_fchown, #endif __NR_setxattr, +#ifdef __NR_setxattrat +__NR_setxattrat, +#endif __NR_lsetxattr, __NR_fsetxattr, __NR_removexattr, +#ifdef __NR_removexattrat +__NR_removexattrat, +#endif __NR_lremovexattr, __NR_fremovexattr, #ifdef __NR_fchownat diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index e619ac10cd23..e06fffc48535 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -338,23 +338,33 @@ asmlinkage long sys_io_uring_register(unsigned int fd, unsigned int op, void __user *arg, unsigned int nr_args); asmlinkage long sys_setxattr(const char __user *path, const char __user *name, const void __user *value, size_t size, int flags); +asmlinkage long sys_setxattrat(int dfd, const char __user *path, unsigned int at_flags, + const char __user *name, + const struct xattr_args __user *args, size_t size); asmlinkage long sys_lsetxattr(const char __user *path, const char __user *name, const void __user *value, size_t size, int flags); asmlinkage long sys_fsetxattr(int fd, const char __user *name, const void __user *value, size_t size, int flags); asmlinkage long sys_getxattr(const char __user *path, const char __user *name, void __user *value, size_t size); +asmlinkage long sys_getxattrat(int dfd, const char __user *path, unsigned int at_flags, + const char __user *name, + struct xattr_args __user *args, size_t size); asmlinkage long sys_lgetxattr(const char __user *path, const char __user *name, void __user *value, size_t size); asmlinkage long sys_fgetxattr(int fd, const char __user *name, void __user *value, size_t size); asmlinkage long sys_listxattr(const char __user *path, char __user *list, size_t size); +asmlinkage long sys_listxattrat(int dfd, const char __user *path, char __user *list, + size_t size, int flags); asmlinkage long sys_llistxattr(const char __user *path, char __user *list, size_t size); asmlinkage long sys_flistxattr(int fd, char __user *list, size_t size); asmlinkage long sys_removexattr(const char __user *path, const char __user *name); +asmlinkage long sys_removexattrat(int dfd, const char __user *path, + const char __user *name, int flags); asmlinkage long sys_lremovexattr(const char __user *path, const char __user *name); asmlinkage long sys_fremovexattr(int fd, const char __user *name); diff --git a/include/uapi/asm-generic/unistd.h b/include/uapi/asm-generic/unistd.h index 75f00965ab15..21b275a8dcd6 100644 --- a/include/uapi/asm-generic/unistd.h +++ b/include/uapi/asm-generic/unistd.h @@ -842,8 +842,18 @@ __SYSCALL(__NR_lsm_set_self_attr, sys_lsm_set_self_attr) #define __NR_lsm_list_modules 461 __SYSCALL(__NR_lsm_list_modules, sys_lsm_list_modules) +/* fs/xattr.c */ +#define __NR_setxattrat 462 +__SYSCALL(__NR_setxattrat, sys_setxattrat) +#define __NR_getxattrat 463 +__SYSCALL(__NR_getxattrat, sys_getxattrat) +#define __NR_listxattrat 464 +__SYSCALL(__NR_listxattrat, sys_listxattrat) +#define __NR_removexattrat 465 +__SYSCALL(__NR_removexattrat, sys_removexattrat) + #undef __NR_syscalls -#define __NR_syscalls 462 +#define __NR_syscalls 466 /* * 32 bit systems traditionally used different diff --git a/include/uapi/linux/xattr.h b/include/uapi/linux/xattr.h index 9463db2dfa9d..e9ac2acc40c3 100644 --- a/include/uapi/linux/xattr.h +++ b/include/uapi/linux/xattr.h @@ -20,6 +20,12 @@ #define XATTR_CREATE 0x1 /* set value, fail if attr already exists */ #define XATTR_REPLACE 0x2 /* set value, fail if attr does not exist */ + +struct xattr_args { + __aligned_u64 __user value; + __u32 size; + __u32 flags; +}; #endif /* Namespaces */