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| author | Robert Jarzmik <robert.jarzmik@free.fr> | 2015-02-08 21:02:09 +0100 |
|---|---|---|
| committer | Brian Norris <computersforpeace@gmail.com> | 2015-02-28 01:22:07 -0800 |
| commit | e423c90a6520d704cd885d742b499dfd6b0f6277 (patch) | |
| tree | 83cac69e9715738b5182021685335c4a6a89028b | |
| parent | 8dad0386b97c4bd6edd56752ca7f2e735fe5beb4 (diff) | |
| download | op-kernel-dev-e423c90a6520d704cd885d742b499dfd6b0f6277.zip op-kernel-dev-e423c90a6520d704cd885d742b499dfd6b0f6277.tar.gz | |
mtd: pxa3xx_nand: fix driver when num_cs is 0
As the devicetree binding doesn't require num_cs to exist or be strictly
positive, and neither does the platform data case, a bug appear when
num_cs is set to 0 and panics the kernel.
The issue is that in alloc_nand_resource(), chip is dereferenced without
having a value assigned when num_cs == 0.
Fix this by returning ENODEV is num_cs == 0.
The panic seen is :
Unable to handle kernel NULL pointer dereference at virtual address 000002b8
pgd = c0004000
[000002b8] *pgd=00000000
Internal error: Oops: 5 [#1] PREEMPT ARM
Modules linked in:
Hardware name: Marvell PXA3xx (Device Tree Support)
task: c3822aa0 ti: c3826000 task.ti: c3826000
PC is at alloc_nand_resource+0x180/0x4a8
LR is at alloc_nand_resource+0xa0/0x4a8
pc : [<c0275b90>] lr : [<c0275ab0>] psr: 68000013
sp : c3827d90 ip : 00000000 fp : 00000000
r10: c3862200 r9 : 0000005e r8 : 00000000
r7 : c3865610 r6 : c3862210 r5 : c3924210 r4 : c3862200
r3 : 00000000 r2 : 00000000 r1 : 00000000 r0 : 00000000
Flags: nZCv IRQs on FIQs on Mode SVC_32 ISA ARM Segment kernel
Control: 0000397f Table: 80004018 DAC: 00000035
Process swapper (pid: 1, stack limit = 0xc3826198)
Stack: (0xc3827d90 to 0xc3828000)
...zip...
[<c0275b90>] (alloc_nand_resource) from [<c0275ff8>] (pxa3xx_nand_probe+0x140/0x978)
[<c0275ff8>] (pxa3xx_nand_probe) from [<c0258c40>] (platform_drv_probe+0x48/0xa4)
[<c0258c40>] (platform_drv_probe) from [<c0257650>] (driver_probe_device+0x80/0x21c)
[<c0257650>] (driver_probe_device) from [<c0257878>] (__driver_attach+0x8c/0x90)
[<c0257878>] (__driver_attach) from [<c0255ec4>] (bus_for_each_dev+0x58/0x88)
[<c0255ec4>] (bus_for_each_dev) from [<c0256ec8>] (bus_add_driver+0xd8/0x1d4)
[<c0256ec8>] (bus_add_driver) from [<c0257f14>] (driver_register+0x78/0xf4)
[<c0257f14>] (driver_register) from [<c00088a8>] (do_one_initcall+0x80/0x1e4)
[<c00088a8>] (do_one_initcall) from [<c048ed08>] (kernel_init_freeable+0xec/0x1b4)
[<c048ed08>] (kernel_init_freeable) from [<c0377d8c>] (kernel_init+0x8/0xe4)
[<c0377d8c>] (kernel_init) from [<c00095f8>] (ret_from_fork+0x14/0x3c)
Code: e503b234 e5953008 e1530001 caffffd1 (e59002b8)
---[ end trace a5770060c8441895 ]---
Signed-off-by: Robert Jarzmik <robert.jarzmik@free.fr>
Acked-by: Ezequiel Garcia <ezequiel.garcia@free-electrons.com>
Signed-off-by: Brian Norris <computersforpeace@gmail.com>
| -rw-r--r-- | drivers/mtd/nand/pxa3xx_nand.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/drivers/mtd/nand/pxa3xx_nand.c b/drivers/mtd/nand/pxa3xx_nand.c index bc67736..10b1f7a 100644 --- a/drivers/mtd/nand/pxa3xx_nand.c +++ b/drivers/mtd/nand/pxa3xx_nand.c @@ -1608,6 +1608,8 @@ static int alloc_nand_resource(struct platform_device *pdev) int ret, irq, cs; pdata = dev_get_platdata(&pdev->dev); + if (pdata->num_cs <= 0) + return -ENODEV; info = devm_kzalloc(&pdev->dev, sizeof(*info) + (sizeof(*mtd) + sizeof(*host)) * pdata->num_cs, GFP_KERNEL); if (!info) |
