From da0510c47519fe0999cffe316e1d370e29f952be Mon Sep 17 00:00:00 2001 From: Sudip Mukherjee Date: Tue, 10 Jan 2017 16:57:45 -0800 Subject: lib/Kconfig.debug: fix frv build failure The build of frv allmodconfig was failing with the errors like: /tmp/cc0JSPc3.s: Assembler messages: /tmp/cc0JSPc3.s:1839: Error: symbol `.LSLT0' is already defined /tmp/cc0JSPc3.s:1842: Error: symbol `.LASLTP0' is already defined /tmp/cc0JSPc3.s:1969: Error: symbol `.LELTP0' is already defined /tmp/cc0JSPc3.s:1970: Error: symbol `.LELT0' is already defined Commit 866ced950bcd ("kbuild: Support split debug info v4") introduced splitting the debug info and keeping that in a separate file. Somehow, the frv-linux gcc did not like that and I am guessing that instead of splitting it started copying. The first report about this is at: https://lists.01.org/pipermail/kbuild-all/2015-July/010527.html. I will try and see if this can work with frv and if still fails I will open a bug report with gcc. But meanwhile this is the easiest option to solve build failure of frv. Fixes: 866ced950bcd ("kbuild: Support split debug info v4") Link: http://lkml.kernel.org/r/1482062348-5352-1-git-send-email-sudipm.mukherjee@gmail.com Signed-off-by: Sudip Mukherjee Reported-by: Fengguang Wu Cc: Andi Kleen Cc: David Howells Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/Kconfig.debug | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'lib') diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index b06848a104e6..eb9e9a7870fa 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -164,7 +164,7 @@ config DEBUG_INFO_REDUCED config DEBUG_INFO_SPLIT bool "Produce split debuginfo in .dwo files" - depends on DEBUG_INFO + depends on DEBUG_INFO && !FRV help Generate debug info into separate .dwo files. This significantly reduces the build directory size for builds with DEBUG_INFO, -- cgit v1.2.3 From b9dc6f65bc5e232d1c05fe34b5daadc7e8bbf1fb Mon Sep 17 00:00:00 2001 From: Al Viro Date: Sat, 14 Jan 2017 19:33:08 -0500 Subject: fix a fencepost error in pipe_advance() The logics in pipe_advance() used to release all buffers past the new position failed in cases when the number of buffers to release was equal to pipe->buffers. If that happened, none of them had been released, leaving pipe full. Worse, it was trivial to trigger and we end up with pipe full of uninitialized pages. IOW, it's an infoleak. Cc: stable@vger.kernel.org # v4.9 Reported-by: "Alan J. Wylie" Tested-by: "Alan J. Wylie" Signed-off-by: Al Viro --- lib/iov_iter.c | 54 +++++++++++++++++++++++++++++++----------------------- 1 file changed, 31 insertions(+), 23 deletions(-) (limited to 'lib') diff --git a/lib/iov_iter.c b/lib/iov_iter.c index 25f572303801..e68604ae3ced 100644 --- a/lib/iov_iter.c +++ b/lib/iov_iter.c @@ -730,43 +730,50 @@ size_t iov_iter_copy_from_user_atomic(struct page *page, } EXPORT_SYMBOL(iov_iter_copy_from_user_atomic); +static inline void pipe_truncate(struct iov_iter *i) +{ + struct pipe_inode_info *pipe = i->pipe; + if (pipe->nrbufs) { + size_t off = i->iov_offset; + int idx = i->idx; + int nrbufs = (idx - pipe->curbuf) & (pipe->buffers - 1); + if (off) { + pipe->bufs[idx].len = off - pipe->bufs[idx].offset; + idx = next_idx(idx, pipe); + nrbufs++; + } + while (pipe->nrbufs > nrbufs) { + pipe_buf_release(pipe, &pipe->bufs[idx]); + idx = next_idx(idx, pipe); + pipe->nrbufs--; + } + } +} + static void pipe_advance(struct iov_iter *i, size_t size) { struct pipe_inode_info *pipe = i->pipe; - struct pipe_buffer *buf; - int idx = i->idx; - size_t off = i->iov_offset, orig_sz; - if (unlikely(i->count < size)) size = i->count; - orig_sz = size; - if (size) { + struct pipe_buffer *buf; + size_t off = i->iov_offset, left = size; + int idx = i->idx; if (off) /* make it relative to the beginning of buffer */ - size += off - pipe->bufs[idx].offset; + left += off - pipe->bufs[idx].offset; while (1) { buf = &pipe->bufs[idx]; - if (size <= buf->len) + if (left <= buf->len) break; - size -= buf->len; + left -= buf->len; idx = next_idx(idx, pipe); } - buf->len = size; i->idx = idx; - off = i->iov_offset = buf->offset + size; - } - if (off) - idx = next_idx(idx, pipe); - if (pipe->nrbufs) { - int unused = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1); - /* [curbuf,unused) is in use. Free [idx,unused) */ - while (idx != unused) { - pipe_buf_release(pipe, &pipe->bufs[idx]); - idx = next_idx(idx, pipe); - pipe->nrbufs--; - } + i->iov_offset = buf->offset + left; } - i->count -= orig_sz; + i->count -= size; + /* ... and discard everything past that point */ + pipe_truncate(i); } void iov_iter_advance(struct iov_iter *i, size_t size) @@ -826,6 +833,7 @@ void iov_iter_pipe(struct iov_iter *i, int direction, size_t count) { BUG_ON(direction != ITER_PIPE); + WARN_ON(pipe->nrbufs == pipe->buffers); i->type = direction; i->pipe = pipe; i->idx = (pipe->curbuf + pipe->nrbufs) & (pipe->buffers - 1); -- cgit v1.2.3