diff options
author | Gustavo A. R. Silva <gustavoars@kernel.org> | 2023-10-02 21:04:15 +0200 |
---|---|---|
committer | Bjorn Helgaas <bhelgaas@google.com> | 2023-10-03 17:13:38 -0500 |
commit | 4a7ce8334965bf175344f49bb933e45fa4db02f5 (patch) | |
tree | da51f8d5970cf27302bdb47b30031aba5742f3f0 /drivers/pci/p2pdma.c | |
parent | 0bb80ecc33a8fb5a682236443c1e740d5c917d1d (diff) |
PCI/P2PDMA: Fix undefined behavior bug in struct pci_p2pdma_pagemap
Struct dev_pagemap is a flexible structure, which means that it contains a
flexible-array member. If dev_pagemap.nr_range > 1, the memory following
the dev_pagemap could be overwritten.
This is currently not an issue because pci_p2pdma_pagemap is not exposed
outside p2pdma.c, and p2pdma.c only sets dev_pagemap.nr_range to 1.
To prevent problems if p2pdma.c ever uses nr_range > 1, move the flexible
struct dev_pagemap to the end of struct pci_p2pdma_pagemap.
-Wflex-array-member-not-at-end is coming in GCC-14, and we are getting
ready to enable it globally.
Link: https://lore.kernel.org/r/ZRsUL/hATNruwtla@work
Signed-off-by: "Gustavo A. R. Silva" <gustavoars@kernel.org>
[bhelgaas: commit log]
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Diffstat (limited to 'drivers/pci/p2pdma.c')
-rw-r--r-- | drivers/pci/p2pdma.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index fa7370f9561a..ab34d3d36a64 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -28,9 +28,9 @@ struct pci_p2pdma { }; struct pci_p2pdma_pagemap { - struct dev_pagemap pgmap; struct pci_dev *provider; u64 bus_offset; + struct dev_pagemap pgmap; }; static struct pci_p2pdma_pagemap *to_p2p_pgmap(struct dev_pagemap *pgmap) |