5.4-stable review patch. If anyone has any objections, please let me know.
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From: NeilBrown neilb@suse.de
[ Upstream commit e8ae8ad479e2d037daa33756e5e72850a7bd37a9 ]
The comment for idr_for_each_entry_ul() states
after normal termination @entry is left with the value NULL
This is not correct in the case where UINT_MAX has an entry in the idr. In that case @entry will be non-NULL after termination. No current code depends on the documentation being correct, but to save future code we should fix it.
Also fix idr_for_each_entry_continue_ul(). While this is not documented as leaving @entry as NULL, the mellanox driver appears to depend on it doing so. So make that explicit in the documentation as well as in the code.
Fixes: e33d2b74d805 ("idr: fix overflow case for idr_for_each_entry_ul()") Cc: Matthew Wilcox willy@infradead.org Cc: Chris Mi chrism@mellanox.com Cc: Cong Wang xiyou.wangcong@gmail.com Signed-off-by: NeilBrown neilb@suse.de Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Sasha Levin sashal@kernel.org --- include/linux/idr.h | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-)
diff --git a/include/linux/idr.h b/include/linux/idr.h index ac6e946b6767b..bbfd934cab226 100644 --- a/include/linux/idr.h +++ b/include/linux/idr.h @@ -200,7 +200,7 @@ static inline void idr_preload_end(void) */ #define idr_for_each_entry_ul(idr, entry, tmp, id) \ for (tmp = 0, id = 0; \ - tmp <= id && ((entry) = idr_get_next_ul(idr, &(id))) != NULL; \ + ((entry) = tmp <= id ? idr_get_next_ul(idr, &(id)) : NULL) != NULL; \ tmp = id, ++id)
/** @@ -224,10 +224,12 @@ static inline void idr_preload_end(void) * @id: Entry ID. * * Continue to iterate over entries, continuing after the current position. + * After normal termination @entry is left with the value NULL. This + * is convenient for a "not found" value. */ #define idr_for_each_entry_continue_ul(idr, entry, tmp, id) \ for (tmp = id; \ - tmp <= id && ((entry) = idr_get_next_ul(idr, &(id))) != NULL; \ + ((entry) = tmp <= id ? idr_get_next_ul(idr, &(id)) : NULL) != NULL; \ tmp = id, ++id)
/*