diff options
| author | Richard Palethorpe <rpalethorpe@suse.com> | 2024-01-10 16:01:22 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2024-02-01 03:19:14 +0300 |
| commit | de66d97add117a7671de515156a3e7b58ffe56f8 (patch) | |
| tree | f4a6dfdf0beac55bf5085994d0333343162b9b74 /include | |
| parent | 500ad5da1df307ed55af9c0ceeba0300cadada9f (diff) | |
| download | linux-de66d97add117a7671de515156a3e7b58ffe56f8.tar.xz | |
x86/entry/ia32: Ensure s32 is sign extended to s64
commit 56062d60f117dccfb5281869e0ab61e090baf864 upstream.
Presently ia32 registers stored in ptregs are unconditionally cast to
unsigned int by the ia32 stub. They are then cast to long when passed to
__se_sys*, but will not be sign extended.
This takes the sign of the syscall argument into account in the ia32
stub. It still casts to unsigned int to avoid implementation specific
behavior. However then casts to int or unsigned int as necessary. So that
the following cast to long sign extends the value.
This fixes the io_pgetevents02 LTP test when compiled with -m32. Presently
the systemcall io_pgetevents_time64() unexpectedly accepts -1 for the
maximum number of events.
It doesn't appear other systemcalls with signed arguments are effected
because they all have compat variants defined and wired up.
Fixes: ebeb8c82ffaf ("syscalls/x86: Use 'struct pt_regs' based syscall calling for IA32_EMULATION and x32")
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Richard Palethorpe <rpalethorpe@suse.com>
Signed-off-by: Nikolay Borisov <nik.borisov@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20240110130122.3836513-1-nik.borisov@suse.com
Link: https://lore.kernel.org/ltp/20210921130127.24131-1-rpalethorpe@suse.com/
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/syscalls.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/include/linux/syscalls.h b/include/linux/syscalls.h index 22bc6bc147f8..bbbd6fac3aff 100644 --- a/include/linux/syscalls.h +++ b/include/linux/syscalls.h @@ -125,6 +125,7 @@ struct cachestat; #define __TYPE_IS_LL(t) (__TYPE_AS(t, 0LL) || __TYPE_AS(t, 0ULL)) #define __SC_LONG(t, a) __typeof(__builtin_choose_expr(__TYPE_IS_LL(t), 0LL, 0L)) a #define __SC_CAST(t, a) (__force t) a +#define __SC_TYPE(t, a) t #define __SC_ARGS(t, a) a #define __SC_TEST(t, a) (void)BUILD_BUG_ON_ZERO(!__TYPE_IS_LL(t) && sizeof(t) > sizeof(long)) |