From: Christoph Hellwig Date: Mon, 23 Mar 2026 07:01:44 +0000 (+0100) Subject: fs: fix archiecture-specific compat_ftruncate64 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=e43dce8a0bc09083ea1145a1a0c61d83cbe72d97;p=thirdparty%2Fkernel%2Flinux.git fs: fix archiecture-specific compat_ftruncate64 The "small" argument to do_sys_ftruncate indicates if > 32-bit size should be reject, but all the arch-specific compat ftruncate64 implementations get this wrong. Merge do_sys_ftruncate and ksys_ftruncate, replace the integer as boolean small flag with a descriptive one about LFS semantics, and use it correctly in the architecture-specific ftruncate64 implementations. Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Fixes: 3dd681d944f6 ("arm64: 32-bit (compat) applications support") Signed-off-by: Christoph Hellwig Link: https://patch.msgid.link/20260323070205.2939118-2-hch@lst.de Reviewed-by: Jan Kara Signed-off-by: Christian Brauner --- diff --git a/arch/arm64/kernel/sys32.c b/arch/arm64/kernel/sys32.c index 96bcfb9074430..12a948f3a5043 100644 --- a/arch/arm64/kernel/sys32.c +++ b/arch/arm64/kernel/sys32.c @@ -89,7 +89,7 @@ COMPAT_SYSCALL_DEFINE4(aarch32_truncate64, const char __user *, pathname, COMPAT_SYSCALL_DEFINE4(aarch32_ftruncate64, unsigned int, fd, u32, __pad, arg_u32p(length)) { - return ksys_ftruncate(fd, arg_u64(length)); + return ksys_ftruncate(fd, arg_u64(length), FTRUNCATE_LFS); } COMPAT_SYSCALL_DEFINE5(aarch32_readahead, int, fd, u32, __pad, diff --git a/arch/mips/kernel/linux32.c b/arch/mips/kernel/linux32.c index a0c0a7a654e94..fe9a787db5694 100644 --- a/arch/mips/kernel/linux32.c +++ b/arch/mips/kernel/linux32.c @@ -60,7 +60,7 @@ SYSCALL_DEFINE4(32_truncate64, const char __user *, path, SYSCALL_DEFINE4(32_ftruncate64, unsigned long, fd, unsigned long, __dummy, unsigned long, a2, unsigned long, a3) { - return ksys_ftruncate(fd, merge_64(a2, a3)); + return ksys_ftruncate(fd, merge_64(a2, a3), FTRUNCATE_LFS); } SYSCALL_DEFINE5(32_llseek, unsigned int, fd, unsigned int, offset_high, diff --git a/arch/parisc/kernel/sys_parisc.c b/arch/parisc/kernel/sys_parisc.c index b2cdbb8a12b16..fcb0d80691392 100644 --- a/arch/parisc/kernel/sys_parisc.c +++ b/arch/parisc/kernel/sys_parisc.c @@ -216,7 +216,7 @@ asmlinkage long parisc_truncate64(const char __user * path, asmlinkage long parisc_ftruncate64(unsigned int fd, unsigned int high, unsigned int low) { - return ksys_ftruncate(fd, (long)high << 32 | low); + return ksys_ftruncate(fd, (long)high << 32 | low, FTRUNCATE_LFS); } /* stubs for the benefit of the syscall_table since truncate64 and truncate @@ -227,7 +227,7 @@ asmlinkage long sys_truncate64(const char __user * path, unsigned long length) } asmlinkage long sys_ftruncate64(unsigned int fd, unsigned long length) { - return ksys_ftruncate(fd, length); + return ksys_ftruncate(fd, length, FTRUNCATE_LFS); } asmlinkage long sys_fcntl64(unsigned int fd, unsigned int cmd, unsigned long arg) { diff --git a/arch/powerpc/kernel/sys_ppc32.c b/arch/powerpc/kernel/sys_ppc32.c index d451a8229223a..03fa487f26147 100644 --- a/arch/powerpc/kernel/sys_ppc32.c +++ b/arch/powerpc/kernel/sys_ppc32.c @@ -101,7 +101,7 @@ PPC32_SYSCALL_DEFINE4(ppc_ftruncate64, unsigned int, fd, u32, reg4, unsigned long, len1, unsigned long, len2) { - return ksys_ftruncate(fd, merge_64(len1, len2)); + return ksys_ftruncate(fd, merge_64(len1, len2), FTRUNCATE_LFS); } PPC32_SYSCALL_DEFINE6(ppc32_fadvise64, diff --git a/arch/sparc/kernel/sys_sparc32.c b/arch/sparc/kernel/sys_sparc32.c index f84a02ab6bf90..04432b82b9e3e 100644 --- a/arch/sparc/kernel/sys_sparc32.c +++ b/arch/sparc/kernel/sys_sparc32.c @@ -58,7 +58,7 @@ COMPAT_SYSCALL_DEFINE3(truncate64, const char __user *, path, u32, high, u32, lo COMPAT_SYSCALL_DEFINE3(ftruncate64, unsigned int, fd, u32, high, u32, low) { - return ksys_ftruncate(fd, ((u64)high << 32) | low); + return ksys_ftruncate(fd, ((u64)high << 32) | low, FTRUNCATE_LFS); } static int cp_compat_stat64(struct kstat *stat, diff --git a/arch/x86/kernel/sys_ia32.c b/arch/x86/kernel/sys_ia32.c index 6cf65397d2257..610a1c2f45191 100644 --- a/arch/x86/kernel/sys_ia32.c +++ b/arch/x86/kernel/sys_ia32.c @@ -61,7 +61,8 @@ SYSCALL_DEFINE3(ia32_truncate64, const char __user *, filename, SYSCALL_DEFINE3(ia32_ftruncate64, unsigned int, fd, unsigned long, offset_low, unsigned long, offset_high) { - return ksys_ftruncate(fd, ((loff_t) offset_high << 32) | offset_low); + return ksys_ftruncate(fd, ((loff_t) offset_high << 32) | offset_low, + FTRUNCATE_LFS); } /* warning: next two assume little endian */ diff --git a/fs/internal.h b/fs/internal.h index cbc384a1aa096..2663823e273a1 100644 --- a/fs/internal.h +++ b/fs/internal.h @@ -199,7 +199,6 @@ extern int build_open_flags(const struct open_how *how, struct open_flags *op); struct file *file_close_fd_locked(struct files_struct *files, unsigned fd); int do_ftruncate(struct file *file, loff_t length, int small); -int do_sys_ftruncate(unsigned int fd, loff_t length, int small); int chmod_common(const struct path *path, umode_t mode); int do_fchownat(int dfd, const char __user *filename, uid_t user, gid_t group, int flag); diff --git a/fs/open.c b/fs/open.c index 91f1139591abe..412d0d6fbaa75 100644 --- a/fs/open.c +++ b/fs/open.c @@ -197,7 +197,7 @@ int do_ftruncate(struct file *file, loff_t length, int small) ATTR_MTIME | ATTR_CTIME, file); } -int do_sys_ftruncate(unsigned int fd, loff_t length, int small) +int ksys_ftruncate(unsigned int fd, loff_t length, unsigned int flags) { if (length < 0) return -EINVAL; @@ -205,18 +205,18 @@ int do_sys_ftruncate(unsigned int fd, loff_t length, int small) if (fd_empty(f)) return -EBADF; - return do_ftruncate(fd_file(f), length, small); + return do_ftruncate(fd_file(f), length, !(flags & FTRUNCATE_LFS)); } SYSCALL_DEFINE2(ftruncate, unsigned int, fd, off_t, length) { - return do_sys_ftruncate(fd, length, 1); + return ksys_ftruncate(fd, length, 0); } #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE2(ftruncate, unsigned int, fd, compat_off_t, length) { - return do_sys_ftruncate(fd, length, 1); + return ksys_ftruncate(fd, length, 0); } #endif @@ -229,7 +229,7 @@ SYSCALL_DEFINE2(truncate64, const char __user *, path, loff_t, length) SYSCALL_DEFINE2(ftruncate64, unsigned int, fd, loff_t, length) { - return do_sys_ftruncate(fd, length, 0); + return ksys_ftruncate(fd, length, FTRUNCATE_LFS); } #endif /* BITS_PER_LONG == 32 */ @@ -245,7 +245,7 @@ COMPAT_SYSCALL_DEFINE3(truncate64, const char __user *, pathname, COMPAT_SYSCALL_DEFINE3(ftruncate64, unsigned int, fd, compat_arg_u64_dual(length)) { - return ksys_ftruncate(fd, compat_arg_u64_glue(length)); + return ksys_ftruncate(fd, compat_arg_u64_glue(length), FTRUNCATE_LFS); } #endif diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 02bd6ddb62782..8787b3511c86c 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -1283,12 +1283,8 @@ static inline long ksys_lchown(const char __user *filename, uid_t user, AT_SYMLINK_NOFOLLOW); } -int do_sys_ftruncate(unsigned int fd, loff_t length, int small); - -static inline long ksys_ftruncate(unsigned int fd, loff_t length) -{ - return do_sys_ftruncate(fd, length, 1); -} +#define FTRUNCATE_LFS (1u << 0) /* allow truncating > 32-bit */ +int ksys_ftruncate(unsigned int fd, loff_t length, unsigned int flags); int do_sys_truncate(const char __user *pathname, loff_t length);