6.10-stable review patch. If anyone has any objections, please let me know.
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From: Carlos López clopez@suse.de
[ Upstream commit 8e64d2356cbc800b4cd0e3e614797f76bcf0cdb8 ]
dasd_add_busid() can return an error via ERR_PTR() if an allocation fails. However, two callsites in dasd_copy_pair_store() do not check the result, potentially resulting in a NULL pointer dereference. Fix this by checking the result with IS_ERR() and returning the error up the stack.
Fixes: a91ff09d39f9b ("s390/dasd: add copy pair setup") Signed-off-by: Carlos López clopez@suse.de Signed-off-by: Stefan Haberland sth@linux.ibm.com Link: https://lore.kernel.org/r/20240715112434.2111291-3-sth@linux.ibm.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/s390/block/dasd_devmap.c | 10 ++++++++-- 1 file changed, 8 insertions(+), 2 deletions(-)
diff --git a/drivers/s390/block/dasd_devmap.c b/drivers/s390/block/dasd_devmap.c index 0316c20823eec..6adaeb985dde1 100644 --- a/drivers/s390/block/dasd_devmap.c +++ b/drivers/s390/block/dasd_devmap.c @@ -2248,13 +2248,19 @@ static ssize_t dasd_copy_pair_store(struct device *dev,
/* allocate primary devmap if needed */ prim_devmap = dasd_find_busid(prim_busid); - if (IS_ERR(prim_devmap)) + if (IS_ERR(prim_devmap)) { prim_devmap = dasd_add_busid(prim_busid, DASD_FEATURE_DEFAULT); + if (IS_ERR(prim_devmap)) + return PTR_ERR(prim_devmap); + }
/* allocate secondary devmap if needed */ sec_devmap = dasd_find_busid(sec_busid); - if (IS_ERR(sec_devmap)) + if (IS_ERR(sec_devmap)) { sec_devmap = dasd_add_busid(sec_busid, DASD_FEATURE_DEFAULT); + if (IS_ERR(sec_devmap)) + return PTR_ERR(sec_devmap); + }
/* setting copy relation is only allowed for offline secondary */ if (sec_devmap->device)