CVE-2026-43380

Summary

In the Linux kernel, the following vulnerability has been resolved:

hwmon: (pmbus/q54sj108a2) fix stack overflow in debugfs read

The q54sj108a2_debugfs_read function suffers from a stack buffer overflow due to incorrect arguments passed to bin2hex(). The function currently passes 'data' as the destination and 'data_char' as the source.

Because bin2hex() converts each input byte into two hex characters, a 32-byte block read results in 64 bytes of output. Since 'data' is only 34 bytes (I2C_SMBUS_BLOCK_MAX + 2), this writes 30 bytes past the end of the buffer onto the stack.

Additionally, the arguments were swapped: it was reading from the zero-initialized 'data_char' and writing to 'data', resulting in all-zero output regardless of the actual I2C read.

Fix this by:

  1. Expanding 'data_char' to 66 bytes to safely hold the hex output.
  2. Correcting the bin2hex() argument order and using the actual read count.
  3. Using a pointer to select the correct output buffer for the final simple_read_from_buffer call.

Affected Software

VendorProductVersion RangeStatus
LinuxLinuxd014538aa38561cd24c5eb228223585f26c5ec71 < a0fc1b9c738fba231f190ab960c83202722efee5affected
LinuxLinuxd014538aa38561cd24c5eb228223585f26c5ec71 < c59090c50f62a17129fc4c5407bc4071305a9e82affected
LinuxLinuxd014538aa38561cd24c5eb228223585f26c5ec71 < 52db5ef163c96f916d424e472fb17aadc35a9f7aaffected
LinuxLinuxd014538aa38561cd24c5eb228223585f26c5ec71 < b48a0f8d4541a4f6651dc9a64430ce9fdf5c120baffected
LinuxLinuxd014538aa38561cd24c5eb228223585f26c5ec71 < 73a7a345816946d276ad2c46c8bb771de67cfc46affected
LinuxLinuxd014538aa38561cd24c5eb228223585f26c5ec71 < 24a7b9daa103fa963b3fd37d8805b23e01621976affected
LinuxLinuxd014538aa38561cd24c5eb228223585f26c5ec71 < 25dd70a03b1f5f3aa71e1a5091ecd9cd2a13ee43affected
LinuxLinux5.11affected
LinuxLinux0 < 5.11unaffected
LinuxLinux5.15.203 <= 5.15.*unaffected
LinuxLinux6.1.167 <= 6.1.*unaffected
LinuxLinux6.6.130 <= 6.6.*unaffected
LinuxLinux6.12.78 <= 6.12.*unaffected
LinuxLinux6.18.19 <= 6.18.*unaffected
LinuxLinux6.19.9 <= 6.19.*unaffected
LinuxLinux7.0 <= *unaffected

Weaknesses

References