diff options
| author | Dan Carpenter <dan.carpenter@linaro.org> | 2023-07-25 20:03:16 +0300 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-07-27 13:07:05 -0700 |
| commit | 641db40f3afe7998011bfabc726dba3e698f8196 (patch) | |
| tree | 9e232cb4b05f967222113114aa8ae4b8fdd4e499 | |
| parent | 286812b041ccc74b114cada5c10ada70a6277a20 (diff) | |
proc/vmcore: fix signedness bug in read_from_oldmem()
The bug is the error handling:
if (tmp < nr_bytes) {
"tmp" can hold negative error codes but because "nr_bytes" is type size_t
the negative error codes are treated as very high positive values
(success). Fix this by changing "nr_bytes" to type ssize_t. The
"nr_bytes" variable is used to store values between 1 and PAGE_SIZE and
they can fit in ssize_t without any issue.
Link: https://lkml.kernel.org/r/b55f7eed-1c65-4adc-95d1-6c7c65a54a6e@moroto.mountain
Fixes: 5d8de293c224 ("vmcore: convert copy_oldmem_page() to take an iov_iter")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
| -rw-r--r-- | fs/proc/vmcore.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c index cb80a7703d58..1fb213f379a5 100644 --- a/fs/proc/vmcore.c +++ b/fs/proc/vmcore.c @@ -132,7 +132,7 @@ ssize_t read_from_oldmem(struct iov_iter *iter, size_t count, u64 *ppos, bool encrypted) { unsigned long pfn, offset; - size_t nr_bytes; + ssize_t nr_bytes; ssize_t read = 0, tmp; int idx; |