diff options
author | Al Viro <viro@zeniv.linux.org.uk> | 2022-10-03 20:26:08 -0400 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2022-10-12 09:39:04 +0200 |
commit | 79bc9ee841abf982affb75c8417abe9091e64304 (patch) | |
tree | b5bf8788d20ab1eaf99407310dd316a166a75587 /fs | |
parent | 2a96b532098284ecf8e4849b8b9e5fc7a28bdee9 (diff) |
fix coredump breakage
commit 4f526fef91b24197d489ff86789744c67f475bb4 upstream.
Let me count the ways in which I'd screwed up:
* when emitting a page, handling of gaps in coredump should happen
before fetching the current file position.
* fix for a problem that occurs on rather uncommon setups (and hadn't
been observed in the wild) had been sent very late in the cycle.
* ... with badly insufficient testing, introducing an easily
reproducible breakage. Without giving it time to soak in -next.
Fucked-up-by: Al Viro <viro@zeniv.linux.org.uk>
Reported-by: "J. R. Okajima" <hooanon05g@gmail.com>
Tested-by: "J. R. Okajima" <hooanon05g@gmail.com>
Fixes: 06bbaa6dc53c "[coredump] don't use __kernel_write() on kmap_local_page()"
Cc: stable@kernel.org # v6.0-only
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/coredump.c | 3 |
1 files changed, 2 insertions, 1 deletions
diff --git a/fs/coredump.c b/fs/coredump.c index 1ab4f5b76a1e..3538f3a63965 100644 --- a/fs/coredump.c +++ b/fs/coredump.c @@ -841,7 +841,7 @@ static int dump_emit_page(struct coredump_params *cprm, struct page *page) }; struct iov_iter iter; struct file *file = cprm->file; - loff_t pos = file->f_pos; + loff_t pos; ssize_t n; if (cprm->to_skip) { @@ -853,6 +853,7 @@ static int dump_emit_page(struct coredump_params *cprm, struct page *page) return 0; if (dump_interrupted()) return 0; + pos = file->f_pos; iov_iter_bvec(&iter, WRITE, &bvec, 1, PAGE_SIZE); n = __kernel_write_iter(cprm->file, &iter, &pos); if (n != PAGE_SIZE) |