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| author | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2024-02-01 14:29:53 -0300 |
|---|---|---|
| committer | Adhemerval Zanella <adhemerval.zanella@linaro.org> | 2024-02-12 11:45:12 -0300 |
| commit | 312e159626b67fe11f39e83e222cf4348a3962f3 (patch) | |
| tree | 2df9a9795a8e5ca9c4107f0b86b5eb4ba4115b78 | |
| parent | 63295e4fda1f6dab4bf7442706fe303bf283036c (diff) | |
| download | glibc-312e159626b67fe11f39e83e222cf4348a3962f3.tar.gz glibc-312e159626b67fe11f39e83e222cf4348a3962f3.tar.xz glibc-312e159626b67fe11f39e83e222cf4348a3962f3.zip | |
mips: FIx clone3 implementation (BZ 31325)
For o32 we need to setup a minimal stack frame to allow cprestore on __thread_start_clone3 (which instruct the linker to save the gp for PIC). Also, there is no guarantee by kABI that $8 will be preserved after syscall execution, so we need to save it on the provided stack. Checked on mipsel-linux-gnu. Reported-by: Khem Raj <raj.khem@gmail.com> Tested-by: Khem Raj <raj.khem@gmail.com> (cherry picked from commit bbd248ac0d75efdef8fe61ea69b1fb25fb95b6e7)
| -rw-r--r-- | sysdeps/unix/sysv/linux/mips/clone3.S | 32 |
1 files changed, 27 insertions, 5 deletions
diff --git a/sysdeps/unix/sysv/linux/mips/clone3.S b/sysdeps/unix/sysv/linux/mips/clone3.S index e9fec2fa47..481b8ae963 100644 --- a/sysdeps/unix/sysv/linux/mips/clone3.S +++ b/sysdeps/unix/sysv/linux/mips/clone3.S @@ -37,11 +37,6 @@ .text .set nomips16 -#if _MIPS_SIM == _ABIO32 -# define EXTRA_LOCALS 1 -#else -# define EXTRA_LOCALS 0 -#endif #define FRAMESZ ((NARGSAVE*SZREG)+ALSZ)&ALMASK GPOFF= FRAMESZ-(1*SZREG) NESTED(__clone3, SZREG, sp) @@ -68,8 +63,31 @@ NESTED(__clone3, SZREG, sp) beqz a0, L(error) /* No NULL cl_args pointer. */ beqz a2, L(error) /* No NULL function pointer. */ +#if _MIPS_SIM == _ABIO32 + /* Both stack and stack_size on clone_args are defined as uint64_t, and + there is no need to handle values larger than to 32 bits for o32. */ +# if __BYTE_ORDER == __BIG_ENDIAN +# define CL_STACKPOINTER_OFFSET 44 +# define CL_STACKSIZE_OFFSET 52 +# else +# define CL_STACKPOINTER_OFFSET 40 +# define CL_STACKSIZE_OFFSET 48 +# endif + + /* For o32 we need to setup a minimal stack frame to allow cprestore + on __thread_start_clone3. Also there is no guarantee by kABI that + $8 will be preserved after syscall execution (so we need to save it + on the provided stack). */ + lw t0, CL_STACKPOINTER_OFFSET(a0) /* Load the stack pointer. */ + lw t1, CL_STACKSIZE_OFFSET(a0) /* Load the stack_size. */ + addiu t1, -32 /* Update the stack size. */ + addu t2, t1, t0 /* Calculate the thread stack. */ + sw a3, 0(t2) /* Save argument pointer. */ + sw t1, CL_STACKSIZE_OFFSET(a0) /* Save the new stack size. */ +#else move $8, a3 /* a3 is set to 0/1 for syscall success/error while a4/$8 is returned unmodified. */ +#endif /* Do the system call, the kernel expects: v0: system call number @@ -125,7 +143,11 @@ L(thread_start_clone3): /* Restore the arg for user's function. */ move t9, a2 /* Function pointer. */ +#if _MIPS_SIM == _ABIO32 + PTR_L a0, 0(sp) +#else move a0, $8 /* Argument pointer. */ +#endif /* Call the user's function. */ jal t9 |