diff options
| author | Ira Weiny <ira.weiny@intel.com> | 2023-11-17 03:03:29 +0300 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2023-12-09 03:14:28 +0300 |
| commit | c65efe3685f5d150eeca5599afeabdc85da899d1 (patch) | |
| tree | 40c85f66f4d34f5df5da9da39b87a0b630d851bd /drivers/cxl | |
| parent | 6f5c4eca48ffe18307b4e1d375817691c9005c87 (diff) | |
| download | linux-c65efe3685f5d150eeca5599afeabdc85da899d1.tar.xz | |
cxl/cdat: Free correct buffer on checksum error
The new 6.7-rc1 kernel now checks the checksum on CDAT data. While
using a branch of Fan's DCD qemu work (and specifying DCD devices), the
following splat was observed.
WARNING: CPU: 1 PID: 1384 at drivers/base/devres.c:1064 devm_kfree+0x4f/0x60
...
RIP: 0010:devm_kfree+0x4f/0x60
...
? devm_kfree+0x4f/0x60
read_cdat_data+0x1a0/0x2a0 [cxl_core]
cxl_port_probe+0xdf/0x200 [cxl_port]
...
The issue in qemu is still unknown but the spat is a straight forward
bug in the CDAT checksum processing code. Use a CDAT buffer variable to
ensure the devm_free() works correctly on error.
Fixes: 670e4e88f3b1 ("cxl: Add checksum verification to CDAT from CXL")
Signed-off-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dave Jiang <dave.jiang@intel.com>
Reviewed-by: Fan Ni <fan.ni@samsung.com>
Reviewed-by: Robert Richter <rrichter@amd.com>
Link: http://lore.kernel.org/r/20231116-fix-cdat-devm-free-v1-1-b148b40707d7@intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/cxl')
| -rw-r--r-- | drivers/cxl/core/pci.c | 13 |
1 files changed, 6 insertions, 7 deletions
diff --git a/drivers/cxl/core/pci.c b/drivers/cxl/core/pci.c index eff20e83d0a6..37e1652afbc7 100644 --- a/drivers/cxl/core/pci.c +++ b/drivers/cxl/core/pci.c @@ -620,7 +620,7 @@ void read_cdat_data(struct cxl_port *port) struct pci_dev *pdev = NULL; struct cxl_memdev *cxlmd; size_t cdat_length; - void *cdat_table; + void *cdat_table, *cdat_buf; int rc; if (is_cxl_memdev(uport)) { @@ -651,16 +651,15 @@ void read_cdat_data(struct cxl_port *port) return; } - cdat_table = devm_kzalloc(dev, cdat_length + sizeof(__le32), - GFP_KERNEL); - if (!cdat_table) + cdat_buf = devm_kzalloc(dev, cdat_length + sizeof(__le32), GFP_KERNEL); + if (!cdat_buf) return; - rc = cxl_cdat_read_table(dev, cdat_doe, cdat_table, &cdat_length); + rc = cxl_cdat_read_table(dev, cdat_doe, cdat_buf, &cdat_length); if (rc) goto err; - cdat_table = cdat_table + sizeof(__le32); + cdat_table = cdat_buf + sizeof(__le32); if (cdat_checksum(cdat_table, cdat_length)) goto err; @@ -670,7 +669,7 @@ void read_cdat_data(struct cxl_port *port) err: /* Don't leave table data allocated on error */ - devm_kfree(dev, cdat_table); + devm_kfree(dev, cdat_buf); dev_err(dev, "Failed to read/validate CDAT.\n"); } EXPORT_SYMBOL_NS_GPL(read_cdat_data, CXL); |