From df19fdcfec7143073b50f9f01af712528bed6d26 Mon Sep 17 00:00:00 2001 From: Joseph Myers Date: Mon, 2 Jan 2017 23:09:25 +0000 Subject: Fix MIPS n32 lseek, lseek64 (bug 21019). The lseek consolidation broke lseek64 for MIPS n32, so resulting in io/test-lfs failing with an incorrect return from ftello64. This configuration uses the lseek syscall with a 64-bit return value; as the C syscall macros return long, they cannot be used in this case and so an assembly implementation is needed; accordingly, this patch adds lseek64 back to syscalls.list for this configuration. lseek was also broken, truncating the result without checking for overflow. lseek however was already broken before the consolidation; it aliased lseek64 so would return an out-of-range value, resulting in architecturally undefined behavior in the caller if it tried to use a non-sign-extended value with a 32-bit instruction. This patch adds a custom lseek implementation in C for n32, which calls __lseek64 to get the 64-bit value then checks for overflow. Because the prior lseek breakage did not show in test results, and the lseek64 breakage showed only indirectly through tests of ftello64, test coverage was clearly inadequate. This patch extends io/test-lfs.c to test the lseek64 return value (at a point where it has already seeked over 2GB into a file), and then to test the lseek return value (with the latter's expectations depending on whether off_t is smaller than off64_t). Tested for mips64 n32. Also tested test-lfs for x86_64 and x86, where as expected it passes. [BZ #21019] * sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list (lseek64): New syscall entry. * sysdeps/unix/sysv/linux/mips/mips64/n32/lseek.c: New file. * io/test-lfs.c (do_test): Test offset returned from lseek64 and lseek. --- sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list | 4 ++++ 1 file changed, 4 insertions(+) (limited to 'sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list') diff --git a/sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list b/sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list index 58fd46a9b9..7af317f69c 100644 --- a/sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list +++ b/sysdeps/unix/sysv/linux/mips/mips64/n32/syscalls.list @@ -1,5 +1,9 @@ # File name Caller Syscall name # args Strong name Weak names +# C syscall macros cannot be used because this syscall has a 64-bit +# return value. +lseek64 - lseek i:iii __lseek64 __libc_lseek64 lseek64 llseek + mmap64 - mmap b:aniiii __mmap64 mmap64 readahead - readahead i:iii __readahead readahead -- cgit 1.4.1