From: Brian Gerst brgerst@gmail.com
commit 2ca408d9c749c32288bc28725f9f12ba30299e8f upstream.
Commit
121b32a58a3a ("x86/entry/32: Use IA32-specific wrappers for syscalls taking 64-bit arguments")
converted native x86-32 which take 64-bit arguments to use the compat handlers to allow conversion to passing args via pt_regs. sys_fanotify_mark() was however missed, as it has a general compat handler. Add a config option that will use the syscall wrapper that takes the split args for native 32-bit.
[ bp: Fix typo in Kconfig help text. ]
Fixes: 121b32a58a3a ("x86/entry/32: Use IA32-specific wrappers for syscalls taking 64-bit arguments") Reported-by: Paweł Jasiak pawel@jasiak.xyz Signed-off-by: Brian Gerst brgerst@gmail.com Signed-off-by: Borislav Petkov bp@suse.de Acked-by: Jan Kara jack@suse.cz Acked-by: Andy Lutomirski luto@kernel.org Link: https://lkml.kernel.org/r/20201130223059.101286-1-brgerst@gmail.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- arch/Kconfig | 6 ++++++ arch/x86/Kconfig | 1 + fs/notify/fanotify/fanotify_user.c | 17 +++++++---------- include/linux/syscalls.h | 24 ++++++++++++++++++++++++ 4 files changed, 38 insertions(+), 10 deletions(-)
--- a/arch/Kconfig +++ b/arch/Kconfig @@ -1053,6 +1053,12 @@ config ARCH_WANT_LD_ORPHAN_WARN by the linker, since the locations of such sections can change between linker versions.
+config ARCH_SPLIT_ARG64 + bool + help + If a 32-bit architecture requires 64-bit arguments to be split into + pairs of 32-bit arguments, select this option. + source "kernel/gcov/Kconfig"
source "scripts/gcc-plugins/Kconfig" --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -18,6 +18,7 @@ config X86_32 select MODULES_USE_ELF_REL select OLD_SIGACTION select GENERIC_VDSO_32 + select ARCH_SPLIT_ARG64
config X86_64 def_bool y --- a/fs/notify/fanotify/fanotify_user.c +++ b/fs/notify/fanotify/fanotify_user.c @@ -1285,26 +1285,23 @@ fput_and_out: return ret; }
+#ifndef CONFIG_ARCH_SPLIT_ARG64 SYSCALL_DEFINE5(fanotify_mark, int, fanotify_fd, unsigned int, flags, __u64, mask, int, dfd, const char __user *, pathname) { return do_fanotify_mark(fanotify_fd, flags, mask, dfd, pathname); } +#endif
-#ifdef CONFIG_COMPAT -COMPAT_SYSCALL_DEFINE6(fanotify_mark, +#if defined(CONFIG_ARCH_SPLIT_ARG64) || defined(CONFIG_COMPAT) +SYSCALL32_DEFINE6(fanotify_mark, int, fanotify_fd, unsigned int, flags, - __u32, mask0, __u32, mask1, int, dfd, + SC_ARG64(mask), int, dfd, const char __user *, pathname) { - return do_fanotify_mark(fanotify_fd, flags, -#ifdef __BIG_ENDIAN - ((__u64)mask0 << 32) | mask1, -#else - ((__u64)mask1 << 32) | mask0, -#endif - dfd, pathname); + return do_fanotify_mark(fanotify_fd, flags, SC_VAL64(__u64, mask), + dfd, pathname); } #endif
--- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -251,6 +251,30 @@ static inline int is_syscall_trace_event static inline long __do_sys##name(__MAP(x,__SC_DECL,__VA_ARGS__)) #endif /* __SYSCALL_DEFINEx */
+/* For split 64-bit arguments on 32-bit architectures */ +#ifdef __LITTLE_ENDIAN +#define SC_ARG64(name) u32, name##_lo, u32, name##_hi +#else +#define SC_ARG64(name) u32, name##_hi, u32, name##_lo +#endif +#define SC_VAL64(type, name) ((type) name##_hi << 32 | name##_lo) + +#ifdef CONFIG_COMPAT +#define SYSCALL32_DEFINE1 COMPAT_SYSCALL_DEFINE1 +#define SYSCALL32_DEFINE2 COMPAT_SYSCALL_DEFINE2 +#define SYSCALL32_DEFINE3 COMPAT_SYSCALL_DEFINE3 +#define SYSCALL32_DEFINE4 COMPAT_SYSCALL_DEFINE4 +#define SYSCALL32_DEFINE5 COMPAT_SYSCALL_DEFINE5 +#define SYSCALL32_DEFINE6 COMPAT_SYSCALL_DEFINE6 +#else +#define SYSCALL32_DEFINE1 SYSCALL_DEFINE1 +#define SYSCALL32_DEFINE2 SYSCALL_DEFINE2 +#define SYSCALL32_DEFINE3 SYSCALL_DEFINE3 +#define SYSCALL32_DEFINE4 SYSCALL_DEFINE4 +#define SYSCALL32_DEFINE5 SYSCALL_DEFINE5 +#define SYSCALL32_DEFINE6 SYSCALL_DEFINE6 +#endif + /* * Called before coming back to user-mode. Returning to user-mode with an * address limit different than USER_DS can allow to overwrite kernel memory.