diff options
| author | peterz@infradead.org <peterz@infradead.org> | 2023-09-21 12:45:07 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2023-09-21 19:22:05 +0200 |
| commit | d6d08d24790e82c69a46ef78ae44fe1b1ed30775 (patch) | |
| tree | f26d08ae2ae9576b64c6f1fccd7ab0e6fee78ef8 | |
| parent | 4923954bbc4a760e0b2210e0cb5733726ac2e2e9 (diff) | |
futex: Extend the FUTEX2 flags
Add the definition for the missing but always intended extra sizes,
and add a NUMA flag for the planned numa extention.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: André Almeida <andrealmeid@igalia.com>
Link: https://lore.kernel.org/r/20230921105247.617057368@noisy.programming.kicks-ass.net
| -rw-r--r-- | include/uapi/linux/futex.h | 21 | ||||
| -rw-r--r-- | kernel/futex/syscalls.c | 9 |
2 files changed, 25 insertions, 5 deletions
diff --git a/include/uapi/linux/futex.h b/include/uapi/linux/futex.h index 21d4eff41162..d2ee625ea189 100644 --- a/include/uapi/linux/futex.h +++ b/include/uapi/linux/futex.h @@ -45,17 +45,32 @@ /* * Flags for futex2 syscalls. + * + * NOTE: these are not pure flags, they can also be seen as: + * + * union { + * u32 flags; + * struct { + * u32 size : 2, + * numa : 1, + * : 4, + * private : 1; + * }; + * }; */ - /* 0x00 */ - /* 0x01 */ +#define FUTEX2_SIZE_U8 0x00 +#define FUTEX2_SIZE_U16 0x01 #define FUTEX2_SIZE_U32 0x02 - /* 0x04 */ +#define FUTEX2_SIZE_U64 0x03 +#define FUTEX2_NUMA 0x04 /* 0x08 */ /* 0x10 */ /* 0x20 */ /* 0x40 */ #define FUTEX2_PRIVATE FUTEX_PRIVATE_FLAG +#define FUTEX2_SIZE_MASK 0x03 + /* do not use */ #define FUTEX_32 FUTEX2_SIZE_U32 /* historical accident :-( */ diff --git a/kernel/futex/syscalls.c b/kernel/futex/syscalls.c index ff696b0e2e5c..953f0a49de3a 100644 --- a/kernel/futex/syscalls.c +++ b/kernel/futex/syscalls.c @@ -183,7 +183,7 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, return do_futex(uaddr, op, val, tp, uaddr2, (unsigned long)utime, val3); } -#define FUTEX2_VALID_MASK (FUTEX2_SIZE_U32 | FUTEX2_PRIVATE) +#define FUTEX2_VALID_MASK (FUTEX2_SIZE_MASK | FUTEX2_PRIVATE) /** * futex_parse_waitv - Parse a waitv array from userspace @@ -207,7 +207,12 @@ static int futex_parse_waitv(struct futex_vector *futexv, if ((aux.flags & ~FUTEX2_VALID_MASK) || aux.__reserved) return -EINVAL; - if (!(aux.flags & FUTEX2_SIZE_U32)) + if (!IS_ENABLED(CONFIG_64BIT) || in_compat_syscall()) { + if ((aux.flags & FUTEX2_SIZE_MASK) == FUTEX2_SIZE_U64) + return -EINVAL; + } + + if ((aux.flags & FUTEX2_SIZE_MASK) != FUTEX2_SIZE_U32) return -EINVAL; futexv[i].w.flags = aux.flags; |