4.9-stable review patch. If anyone has any objections, please let me know.
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From: Mauricio Faria de Oliveira mfo@canonical.com
[ Upstream commit 14cb2c8a6c5dae57ee3e2da10fa3db2b9087e39e ]
The if-block that sets a successful return value in aix_partition() uses 'lvip[].pps_per_lv' and 'n[].name' potentially uninitialized.
For example, if 'numlvs' is zero or alloc_lvn() fails, neither is initialized, but are used anyway if alloc_pvd() succeeds after it.
So, make the alloc_pvd() call conditional on their initialization.
This has been hit when attaching an apparently corrupted/stressed AIX LUN, misleading the kernel to pr_warn() invalid data and hang.
[...] partition (null) (11 pp's found) is not contiguous [...] partition (null) (2 pp's found) is not contiguous [...] partition (null) (3 pp's found) is not contiguous [...] partition (null) (64 pp's found) is not contiguous
Fixes: 6ceea22bbbc8 ("partitions: add aix lvm partition support files") Signed-off-by: Mauricio Faria de Oliveira mfo@canonical.com Signed-off-by: Jens Axboe axboe@kernel.dk Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- block/partitions/aix.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-)
--- a/block/partitions/aix.c +++ b/block/partitions/aix.c @@ -177,7 +177,7 @@ int aix_partition(struct parsed_partitio u32 vgda_sector = 0; u32 vgda_len = 0; int numlvs = 0; - struct pvd *pvd; + struct pvd *pvd = NULL; struct lv_info { unsigned short pps_per_lv; unsigned short pps_found; @@ -231,10 +231,11 @@ int aix_partition(struct parsed_partitio if (lvip[i].pps_per_lv) foundlvs += 1; } + /* pvd loops depend on n[].name and lvip[].pps_per_lv */ + pvd = alloc_pvd(state, vgda_sector + 17); } put_dev_sector(sect); } - pvd = alloc_pvd(state, vgda_sector + 17); if (pvd) { int numpps = be16_to_cpu(pvd->pp_count); int psn_part1 = be32_to_cpu(pvd->psn_part1);