diff options
| author | Al Viro <viro@zeniv.linux.org.uk> | 2022-10-03 20:26:08 -0400 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2022-10-03 20:28:38 -0400 |
| commit | 4f526fef91b24197d489ff86789744c67f475bb4 (patch) | |
| tree | a5571940e6118d12dacb7f94586e331c6de80277 | |
| parent | 4fe89d07dcc2804c8b562f6c7896a45643d34b2f (diff) | |
[brown paperbag] fix coredump breakage
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>
| -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) |