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authorAlexander Sverdlin2020-10-05 10:48:03 +0200
committerVignesh Raghavendra2020-10-28 22:36:30 +0530
commit69a8eed58cc09aea3b01a64997031dd5d3c02c07 (patch)
tree69ba957b4e109c1ada9c093759fa4086a9b254e4 /drivers/mtd
parent3aee8a3a88fa533b74fb75640ca23001358e5476 (diff)
mtd: spi-nor: Don't copy self-pointing struct around
spi_nor_parse_sfdp() modifies the passed structure so that it points to itself (params.erase_map.regions to params.erase_map.uniform_region). This makes it impossible to copy the local struct anywhere else. Therefore only use memcpy() in backup-restore scenario. The bug may show up like below: BUG: unable to handle page fault for address: ffffc90000b377f8 Oops: 0000 [#1] PREEMPT SMP NOPTI CPU: 4 PID: 3500 Comm: flashcp Tainted: G O 5.4.53-... #1 ... RIP: 0010:spi_nor_erase+0x8e/0x5c0 Code: 64 24 18 89 db 4d 8b b5 d0 04 00 00 4c 89 64 24 18 4c 89 64 24 20 eb 12 a8 10 0f 85 59 02 00 00 49 83 c6 10 0f 84 4f 02 00 00 <49> 8b 06 48 89 c2 48 83 e2 c0 48 89 d1 49 03 4e 08 48 39 cb 73 d8 RSP: 0018:ffffc9000217fc48 EFLAGS: 00010206 RAX: 0000000000740000 RBX: 0000000000000000 RCX: 0000000000740000 RDX: ffff8884550c9980 RSI: ffff88844f9c0bc0 RDI: ffff88844ede7bb8 RBP: 0000000000740000 R08: ffffffff815bfbe0 R09: ffff88844f9c0bc0 R10: 0000000000000000 R11: 0000000000000000 R12: ffffc9000217fc60 R13: ffff88844ede7818 R14: ffffc90000b377f8 R15: 0000000000000000 FS: 00007f4699780500(0000) GS:ffff88846ff00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: ffffc90000b377f8 CR3: 00000004538ee000 CR4: 0000000000340fe0 Call Trace: part_erase+0x27/0x50 mtdchar_ioctl+0x831/0xba0 ? filemap_map_pages+0x186/0x3d0 ? do_filp_open+0xad/0x110 ? _copy_to_user+0x22/0x30 ? cp_new_stat+0x150/0x180 mtdchar_unlocked_ioctl+0x2a/0x40 do_vfs_ioctl+0xa0/0x630 ? __do_sys_newfstat+0x3c/0x60 ksys_ioctl+0x70/0x80 __x64_sys_ioctl+0x16/0x20 do_syscall_64+0x6a/0x200 ? prepare_exit_to_usermode+0x50/0xd0 entry_SYSCALL_64_after_hwframe+0x44/0xa9 RIP: 0033:0x7f46996b6817 Cc: stable@vger.kernel.org Fixes: c46872170a54 ("mtd: spi-nor: Move erase_map to 'struct spi_nor_flash_parameter'") Co-developed-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com> Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@nokia.com> Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com> Signed-off-by: Vignesh Raghavendra <vigneshr@ti.com> Tested-by: Baurzhan Ismagulov <ibr@radix50.net> Reviewed-by: Tudor Ambarus <tudor.ambarus@microchip.com> Link: https://lore.kernel.org/r/20201005084803.23460-1-alexander.sverdlin@nokia.com
Diffstat (limited to 'drivers/mtd')
-rw-r--r--drivers/mtd/spi-nor/core.c5
1 files changed, 2 insertions, 3 deletions
diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index 0369d98b2d12..b37d6c1936de 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -2701,11 +2701,10 @@ static void spi_nor_sfdp_init_params(struct spi_nor *nor)
memcpy(&sfdp_params, nor->params, sizeof(sfdp_params));
- if (spi_nor_parse_sfdp(nor, &sfdp_params)) {
+ if (spi_nor_parse_sfdp(nor, nor->params)) {
+ memcpy(nor->params, &sfdp_params, sizeof(*nor->params));
nor->addr_width = 0;
nor->flags &= ~SNOR_F_4B_OPCODES;
- } else {
- memcpy(nor->params, &sfdp_params, sizeof(*nor->params));
}
}