Messages in this thread Patch in this message | | | From | Kautuk Consul <> | Subject | [PATCH 1/1] swapfile: swap_info_get: Check for swap_info[type] == NULL | Date | Mon, 26 Dec 2011 17:26:39 +0530 |
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From: Kautuk Consul <consul.kautuk@gmail.com>
If the swapfile type encoded within entry.val is corrupted in such a way that the swap_info[type] == NULL, then the code in swap_info_get will cause a NULL pointer exception.
Assuming that the code in swap_info_get attempts to validate the swapfile type by checking its range, another bad_nofile check would be to check for check whether the swap_info[type] pointer is NULL.
Adding a NULL check for swap_info[type] to be reagrded as a "bad_nofile" error scenario.
Signed-off-by: Kautuk Consul <consul.kautuk@gmail.com> --- mm/swapfile.c | 2 ++ 1 files changed, 2 insertions(+), 0 deletions(-)
diff --git a/mm/swapfile.c b/mm/swapfile.c index b1cd120..7bdbe91 100644 --- a/mm/swapfile.c +++ b/mm/swapfile.c @@ -483,6 +483,8 @@ static struct swap_info_struct *swap_info_get(swp_entry_t entry) if (type >= nr_swapfiles) goto bad_nofile; p = swap_info[type]; + if (!p) + goto bad_nofile; if (!(p->flags & SWP_USED)) goto bad_device; offset = swp_offset(entry); -- 1.7.6
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