linux_old1/drivers/mtd/chips
Linus Walleij 87a73eb5b5 mtd: jedec_probe: Fix crash in jedec_read_mfr()
It turns out that the loop where we read manufacturer
jedec_read_mfd() can under some circumstances get a
CFI_MFR_CONTINUATION repeatedly, making the loop go
over all banks and eventually hit the end of the
map and crash because of an access violation:

Unable to handle kernel paging request at virtual address c4980000
pgd = (ptrval)
[c4980000] *pgd=03808811, *pte=00000000, *ppte=00000000
Internal error: Oops: 7 [#1] PREEMPT ARM
CPU: 0 PID: 1 Comm: swapper Not tainted 4.16.0-rc1+ #150
Hardware name: Gemini (Device Tree)
PC is at jedec_probe_chip+0x6ec/0xcd0
LR is at 0x4
pc : [<c03a2bf4>]    lr : [<00000004>]    psr: 60000013
sp : c382dd18  ip : 0000ffff  fp : 00000000
r10: c0626388  r9 : 00020000  r8 : c0626340
r7 : 00000000  r6 : 00000001  r5 : c3a71afc  r4 : c382dd70
r3 : 00000001  r2 : c4900000  r1 : 00000002  r0 : 00080000
Flags: nZCv  IRQs on  FIQs on  Mode SVC_32  ISA ARM  Segment none
Control: 0000397f  Table: 00004000  DAC: 00000053
Process swapper (pid: 1, stack limit = 0x(ptrval))

Fix this by breaking the loop with a return 0 if
the offset exceeds the map size.

Fixes: 5c9c11e1c4 ("[MTD] [NOR] Add support for flash chips with ID in bank other than 0")
Cc: <stable@vger.kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
2018-03-29 19:29:06 +02:00
..
Kconfig mtd: avoid stack overflow in MTD CFI code 2016-04-03 16:46:24 -07:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cfi_cmdset_0001.c mtd: cfi_cmdset_0001: fixing memory leak and handling failed kmalloc 2016-01-06 17:23:10 -08:00
cfi_cmdset_0002.c drivers/mtd: Convert remaining uses of pr_warning to pr_warn 2017-04-19 13:10:54 -07:00
cfi_cmdset_0020.c mtd: cfi_cmdset_0020: Drop unnecessary static 2017-05-11 11:49:20 -07:00
cfi_probe.c mtd: cfi: Remove unnecessary OOM messages 2014-03-10 22:42:25 -07:00
cfi_util.c mtd: cfi: deinline large functions 2015-05-27 12:42:16 -07:00
chipreg.c mtd: simplify return logic in do_map_probe() 2012-03-27 00:35:06 +01:00
fwh_lock.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
gen_probe.c mtd: gen_probe: Remove unnecessary OOM messages 2014-03-10 22:42:25 -07:00
jedec_probe.c mtd: jedec_probe: Fix crash in jedec_read_mfr() 2018-03-29 19:29:06 +02:00
map_absent.c mtd: remove retlen zeroing duplication 2012-03-27 00:29:34 +01:00
map_ram.c mtd: remove the get_unmapped_area method 2017-11-13 21:39:18 +01:00
map_rom.c mtd: remove the get_unmapped_area method 2017-11-13 21:39:18 +01:00